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1.
Front Psychiatry ; 13: 1029653, 2022.
Article in English | MEDLINE | ID: mdl-36699498

ABSTRACT

Backgrounds: Hikikomori, pathological social withdrawal, is becoming a crucial mental health issue in Japan and worldwide. We have developed a 3-day family intervention program for hikikomori sufferers based on Mental Health First Aid (MHFA) and Community Reinforcement and Family Training (CRAFT). This study aims to confirm the effectiveness of the 3-day program by a randomized controlled trial. Methods: This study was registered on the UMIN Clinical Trials Registry (UMIN000037289). Fifteen parents were assigned to the treat as usual (TAU) group (TAU only; Age Mean, 65.6; SD, 7.8), and 14 to the Program group (program + TAU; Age Mean, 67.9; SD, 8.6). This study was discontinued due to the COVID-19 pandemic; the recruitment rate was 36.3% of our target sample size of 80. Results: Perceived skills improved temporally and stigma temporally worsened in the TAU group. Confidence decreased and attitude showed no change in both groups. Aggressive behaviors of hikikomori sufferers were significantly worsened in the Program group; however, no serious domestic violence was reported. In the TAU group, Avoidance and irregular life patterns were improved. Activity levels were worsened in both groups. Two participants (16.7%) in the Program group and one participant (7.7%) in the TAU group reported actual behavioral changes (e.g., utilizing support). Conclusion: We could not draw general conclusions on the effectiveness of the program due to the study discontinuation. Nevertheless, this study indicates the necessity for revision of the program to improve family members' confidence in engaging with hikikomori sufferers, with safer approaching by families.

2.
Heliyon ; 6(1): e03011, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31938741

ABSTRACT

BACKGROUNDS: Hikikomori, a severe form of social withdrawal, is increasingly a serious mental health issue worldwide. Hikikomori is comorbid with various psychiatric conditions including depression, social anxiety and suicidal behaviors. Family support is encouraged as a vital first step, however evidence-based programs have yet to be established. Mental Health First Aid (MHFA) is one of the most well-validated educational programs encouraging lay people such as family members, to support close persons suffering from various psychiatric conditions such as depression, anxiety and suicidal behaviors. METHODS: We newly developed an educational program for family members of hikikomori sufferers mainly based on MHFA and 'Community Reinforcement and Family Training (CRAFT)' with role-play and homework. As a single-arm trial, 21 parents (7 fathers and 14 mothers) living with hikikomori sufferers participated in our program with five once-a-week sessions (2 h per session) and six monthly follow-ups, and its effectiveness was evaluated using various self-rated questionnaires. RESULTS: Perceived skills toward a depressed hikikomori case vignette, stigma held by participants, and subscales of two problematic and one adaptive behaviors of hikikomori sufferers were improved throughout the sessions and follow-ups. In addition, positive behavioral changes of hikikomori sufferers such as improved social participation were reported by participants. LIMITATIONS: Single-arm design and evaluation using self-rated questionnaires are the main limitations of the present study. CONCLUSIONS: Our newly developed program has positive effects on family members in their contact and support of hikikomori sufferers. Future trials with control groups are required to validate the effectiveness of this program.

3.
Arch Virol ; 162(4): 931-941, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27942974

ABSTRACT

We constructed turkey herpesvirus (HVT) vector vaccines in which the VP2 gene of infectious bursal disease virus (IBDV) was inserted into the HVT genome in the following regions: UL3-4, UL22-23, UL45-46, and US10-SORF3. We then evaluated the relationship between the gene insertion site and the capacity of the virus to elicit antibodies. rHVT/IBD (US10) showed good growth activity in vitro, with growth comparable to that of the parent HVT. On the other hand, rHVT/IBD (UL3-4), rHVT/IBD (UL22-23), and rHVT/IBD (UL45-46) exhibited decreased growth activity in chicken embryo fibroblast (CEF) cells compared to the parent HVT. However, the rHVT/IBD (US10) elicited lower levels of virus-neutralizing (VN) antibodies compared to the other constructs. rHVT/IBD (UL3-4) and rHVT/IBD (UL45-46) appeared to be similar in their ability to elicit VN antibodies. Based on the results of in vitro and in vivo assays, rHVT/IBD (UL3-4) was selected for further testing. In a challenge assay, rHVT/IBD (UL3-4) protected chickens from challenge with virulent Marek's disease virus serotype 1 and IBDV. In conclusion, the site of gene insertion may have a strong effect on the growth of the vector virus in vitro and its antibody-eliciting capacity. Insertions in the UL3-4 region permitted a balance between growth activity and VN-antibody-eliciting capacity, and this region might therefore be an appropriate insertion site for IBDV VP2.


Subject(s)
Antibodies, Viral/immunology , Herpesvirus 1, Meleagrid/immunology , Marek Disease/prevention & control , Poultry Diseases/prevention & control , Viral Proteins/immunology , Viral Vaccines/immunology , Animals , Chickens , Herpesvirus 1, Meleagrid/chemistry , Herpesvirus 1, Meleagrid/genetics , Herpesvirus 1, Meleagrid/growth & development , Herpesvirus 2, Gallid/immunology , Herpesvirus 2, Gallid/physiology , Marek Disease/immunology , Marek Disease/virology , Mutagenesis, Insertional , Poultry Diseases/immunology , Poultry Diseases/virology , Turkeys , Vaccination , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/chemistry , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Viral Proteins/administration & dosage , Viral Proteins/chemistry , Viral Proteins/genetics , Viral Vaccines/administration & dosage , Viral Vaccines/chemistry , Viral Vaccines/genetics
4.
Nat Commun ; 7: 10573, 2016 Feb 03.
Article in English | MEDLINE | ID: mdl-26838180

ABSTRACT

The insulin/IGF-1 signalling (IIS) pathway plays an important role in the regulation of larval diapause, the long-lived growth arrest state called dauer arrest, in Caenorhabditis elegans. In this nematode, 40 insulin-like peptides (ILPs) have been identified as putative ligands of the IIS pathway; however, it remains unknown how ILPs modulate larval diapause. Here we show that the secretory polarity of INS-35 and INS-7, which suppress larval diapause, is changed in the intestinal epithelial cells at larval diapause. These ILPs are secreted from the intestine into the body cavity during larval stages. In contrast, they are secreted into the intestinal lumen and degraded during dauer arrest, only to be secreted into the body cavity again when the worms return to developmental growth. The process that determines the secretory polarity of INS-35 and INS-7, thus, has an important role in the modulation of larval diapause.


Subject(s)
Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans/genetics , Cell Polarity , Epithelial Cells/metabolism , Growth and Development/genetics , Intestinal Mucosa/metabolism , Somatomedins/genetics , Animals , Blotting, Western , Caenorhabditis elegans Proteins/metabolism , Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/metabolism , Insulins , Intestinal Mucosa/cytology , Larva , Life Cycle Stages , Microscopy, Fluorescence , Peptide Hormones/genetics , Peptide Hormones/metabolism , Receptor, Insulin/genetics , Receptor, Insulin/metabolism , Somatomedins/metabolism
5.
J Aging Res ; 2015: 425261, 2015.
Article in English | MEDLINE | ID: mdl-25789174

ABSTRACT

Royal jelly (RJ) produced by honeybees has been reported to possess diverse health-beneficial properties and has been implicated to have a function in longevity across diverse species as well as honeybees. 10-Hydroxy-2-decenoic acid (10-HDA), the major lipid component of RJ produced by honeybees, was previously shown to increase the lifespan of Caenorhabditis elegans. The objective of this study is to elucidate signaling pathways that are involved in the lifespan extension by 10-HDA. 10-HDA further extended the lifespan of the daf-2 mutants, which exhibit long lifespan through reducing insulin-like signaling (ILS), indicating that 10-HDA extended lifespan independently of ILS. On the other hand, 10-HDA did not extend the lifespan of the eat-2 mutants, which show long lifespan through dietary restriction caused by a food-intake defect. This finding indicates that 10-HDA extends lifespan through dietary restriction signaling. We further found that 10-HDA did not extend the lifespan of the long-lived mutants in daf-15, which encodes Raptor, a target of rapamycin (TOR) components, indicating that 10-HDA shared some longevity control mechanisms with TOR signaling. Additionally, 10-HDA was found to confer tolerance against thermal and oxidative stress. 10-HDA increases longevity not through ILS but through dietary restriction and TOR signaling in C. elegans.

6.
BMC Psychiatry ; 14: 146, 2014 May 21.
Article in English | MEDLINE | ID: mdl-24886087

ABSTRACT

BACKGROUND: Because psychiatric disorders are risk factors for suicide, psychiatric consultation should be an essential element of suicide prevention among individuals with a high risk of suicide. The aim of the present study was to compare the characteristics of individuals who had or had not received psychiatric consultation before they attempted suicide in Japan. METHODS: Clinical records were used to identify 300 consecutive persons who were admitted to the hospital for attempting suicide between April 2006 and March 2013. We divided the patients into two groups. One group consisted of patients who consulted a psychiatrist before their suicidal behaviours (the consultation group), and the other group consisted of patients who had not consulted a psychiatrist before their suicidal behaviours (the non-consultation group). Group differences were analysed with respect to gender, age, method of suicide attempts, psychiatric diagnosis (ICD-10), and duration of hospitalisation in the emergency unit. RESULTS: Females tended to be over-represented in the consultation group (73.0%), and males tended to be over-represented in the non-consultation group (59.8%). Poisoning by prescription drugs was used more frequently as a method of suicide in the consultation group than in the non-consultation group. Neuroticism and related disorders were higher in the non-consultation group (33.7%) than in the consultation group (18.9%). Mood disorders (32.6%) were nearly as common as neuroticism in the non-consultation group, and together they accounted for almost two-thirds of all diagnoses. Mood disorders were comparable between the consultation group (30.9%) and the non-consultation group (32.6%). Adult personality disorders (13.3%) and schizophrenia and related disorders (26.0%) were higher in the consultation group than in the non-consultation group. CONCLUSIONS: Measures have to be taken to encourage people with these diverse characteristics to consult psychiatrists, and psychiatrists have to regularly evaluate patients for suicide risk. Furthermore, we need further research on the relationship between psychiatric consultation and poisoning by prescribed drugs.


Subject(s)
Mental Disorders/epidemiology , Referral and Consultation/statistics & numerical data , Suicidal Ideation , Suicide, Attempted/psychology , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Emergency Service, Hospital , Female , Hospitalization , Humans , Japan/epidemiology , Male , Middle Aged , Mood Disorders/epidemiology , Risk Factors , Young Adult
7.
Gerontology ; 60(2): 138-42, 2014.
Article in English | MEDLINE | ID: mdl-24217152

ABSTRACT

The prospect of space travel continues to capture the imagination. Several competing companies are now promising flights for the general population. Previously, it was recognized that many of the physiological changes that occur with spaceflight are similar to those seen with normal ageing. This led to the notion that spaceflight can be used as a model of accelerated ageing and raised concerns about the safety of individuals engaging in space travel. Paradoxically, however, space travel has been recently shown to be beneficial to some aspects of muscle health in the tiny worm Caenorhabditis elegans. C. elegans is a commonly used laboratory animal for studying ageing. C. elegans displays age-related decline of some biological processes observed in ageing humans, and about 35% of C. elegans' genes have human homologs. Space flown worms were found to have decreased expression of a number of genes that increase lifespan when expressed at lower levels. These changes were accompanied by decreased accumulation of toxic protein aggregates in ageing worms' muscles. Thus, in addition to spaceflight producing physiological changes that are similar to accelerated ageing, it also appears to produce some changes similar to delayed ageing. Here, we put forward the hypothesis that in addition to the previously well-appreciated mechanotransduction changes, neural and endocrine signals are altered in response to spaceflight and that these may have both negative (e.g. less muscle protein) and some positive consequences (e.g. healthier muscles), at least for invertebrates, with respect to health in space. Given that changes in circulating hormones are well documented with age and in astronauts, our view is that further research into the relationship between metabolic control, ageing, and adaptation to the environment should be productive in advancing our understanding of the physiology of both spaceflight and ageing.


Subject(s)
Aging/physiology , Caenorhabditis elegans/physiology , Space Flight , Adaptation, Physiological , Aging/genetics , Animals , Caenorhabditis elegans/genetics , Energy Metabolism , Gene Expression , Genes, Helminth , Humans , Longevity/physiology , Models, Animal , Models, Biological , Muscles/physiology , Weightlessness/adverse effects
8.
Mol Cell Biochem ; 381(1-2): 145-56, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23881245

ABSTRACT

11ß-hydroxysteroid dehydrogenase (HSD11B) catalyzes the interconversion between active and inactive glucocorticoid, and is known to exist as two distinct isozymes: HSD11B1 and HSD11B2. A third HSD11B isozyme, HSD11B1L (SCDR10b), has recently been identified. Human HSD11B1L, which was characterized as a unidirectional NADP(+)-dependent cortisol dehydrogenase, appears to be specifically expressed in the brain. We previously reported that HSD11B1 and abundant HSD11B2 isozymes are expressed in neonatal pig testis and the Km for cortisol of NADP(+)-dependent dehydrogenase activity of testicular microsomes obviously differs from the same activity catalyzed by HSD11B1 from pig liver microsomes. Therefore, we hypothesized that the neonatal pig testis also expresses the third type of HSD11B isozyme, and we herein examined further evidence regarding the expression of HSD11B1L. (1) The inhibitory effects of gossypol and glycyrrhetinic acid on pig testicular microsomal NADP(+)-dependent cortisol dehydrogenase activity was clearly different from that of pig liver microsomes. (2) A highly conserved human HSD11B1L sequence was observed by RT-PCR in a pig testicular cDNA library. (3) mRNA, which contains the amplified sequence, was evaluated by real-time PCR and was most strongly expressed in pig brain, and at almost the same levels in the kidney as in the testis, but at lower levels in the liver. Based on these results, neonatal pig testis appears to express glycyrrhetinic acid-resistant HSD11B1L as a third HSD11B isozyme, and it may play a physiologically important role in cooperation with the abundantly expressed HSD11B2 isozyme in order to prevent Leydig cell apoptosis or GC-mediated suppression of testosterone production induced by high concentrations of activated GC in neonatal pig testis.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenases/metabolism , Sus scrofa/metabolism , Testis/enzymology , 11-beta-Hydroxysteroid Dehydrogenases/antagonists & inhibitors , 11-beta-Hydroxysteroid Dehydrogenases/chemistry , 11-beta-Hydroxysteroid Dehydrogenases/genetics , Amino Acid Sequence , Animals , Animals, Newborn , Base Sequence , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Gene Expression Profiling , Gene Expression Regulation, Enzymologic/drug effects , Humans , Male , Microsomes, Liver/drug effects , Microsomes, Liver/enzymology , Molecular Sequence Data , NADP/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Testis/drug effects
9.
BMC Genomics ; 14: 248, 2013 Apr 15.
Article in English | MEDLINE | ID: mdl-23586671

ABSTRACT

BACKGROUND: Senescence-accelerated mice (SAM) are a series of mouse strains originally derived from unexpected crosses between AKR/J and unknown mice, from which phenotypically distinct senescence-prone (SAMP) and -resistant (SAMR) inbred strains were subsequently established. Although SAMP strains have been widely used for aging research focusing on their short life spans and various age-related phenotypes, such as immune dysfunction, osteoporosis, and brain atrophy, the responsible gene mutations have not yet been fully elucidated. RESULTS: To identify mutations specific to SAMP strains, we performed whole exome sequencing of 6 SAMP and 3 SAMR strains. This analysis revealed 32,019 to 38,925 single-nucleotide variants in the coding region of each SAM strain. We detected Ogg1 p.R304W and Mbd4 p.D129N deleterious mutations in all 6 of the SAMP strains but not in the SAMR or AKR/J strains. Moreover, we extracted 31 SAMP-specific novel deleterious mutations. In all SAMP strains except SAMP8, we detected a p.R473W missense mutation in the Ldb3 gene, which has been associated with myofibrillar myopathy. In 3 SAMP strains (SAMP3, SAMP10, and SAMP11), we identified a p.R167C missense mutation in the Prx gene, in which mutations causing hereditary motor and sensory neuropathy (Dejerine-Sottas syndrome) have been identified. In SAMP6 we detected a p.S540fs frame-shift mutation in the Il4ra gene, a mutation potentially causative of ulcerative colitis and osteoporosis. CONCLUSIONS: Our data indicate that different combinations of mutations in disease-causing genes may be responsible for the various phenotypes of SAMP strains.


Subject(s)
Aging/genetics , Disease/genetics , Exome/genetics , Genomics , Mutation/genetics , Sequence Analysis , Amino Acid Sequence , Animals , Base Sequence , Exons/genetics , Humans , Membrane Proteins/chemistry , Membrane Proteins/genetics , Mice , Molecular Sequence Data , Phenotype , Species Specificity
10.
Int J Med Sci ; 9(7): 555-66, 2012.
Article in English | MEDLINE | ID: mdl-22991494

ABSTRACT

INTRODUCTION: Agonists of peroxisome proliferator-activated receptor gamma (PPARγ) have been examined as chemopreventive and chemotherapeutic agents. The aim was to investigate the cytotoxicity and action mechanisms of 15-deoxy-Δ(12,14)-prostaglandin J(2) (15d-PGJ(2)), one of endogenous ligands for PPARγ, in terms of PPARγ-dependency and the mitogen-activated protein kinase (MAPK) and Akt pathway in three human renal cell carcinoma (RCC)-derived cell lines. METHODS: 786-O, Caki-2 and ACHN cells were used as human RCC-derived cell lines. Cell viability and caspase-3 activity was detected by fluorescent reagents, and chromatin-condensation was observed with a brightfield fluorescent microscope after staining cells with Hoechst33342. The expression levels of proteins were detected by Western blot analysis. RESULTS: 15d-PGJ(2) showed cytotoxicity in dose-dependent manner. 15d-PGJ(2) induced chromatin-condensation and elevated caspase-3 activity, and the cell viability was restored by co-treatment with a pan-caspase inhibitor, Z-VAD-FMK, indicating the involvement of caspase-dependent apoptosis. The cytotoxicity was not impaired by a PPARγ inhibitor, GW9662, suggesting that 15d-PGJ(2) exerted the cytotoxicity in a PPARγ-independent manner. Some antioxidants rescued cells from cell death induced by 15d-PGJ(2), but some did not, suggesting that reactive oxygen species (ROS) did not contribute to the apoptosis. 15d-PGJ(2) also increased the expression levels of phospho-c-Jun N terminal kinase (JNK) in Caki-2 cells, and decreased those of phospho-Akt in 786-O cells, indicating that the JNK MAPK and the Akt pathways participated in the anticancer effects of 15d-PGJ(2) in some cell lines. CONCLUSION: 15d-PGJ(2) exerted cytotoxic effects accompanying caspase-dependent apoptosis, and this effect was elicited in a PPARγ-independent manner in three cell lines. In addition, the JNK MAPK and Akt pathway was involved in the cytotoxicity of 15d-PGJ(2) to some extent in some cell line. Therefore, our study showed the 15d-PGJ(2) to potentially be an interesting approach for RCC treatment.


Subject(s)
Carcinoma, Renal Cell/metabolism , Kidney Neoplasms/metabolism , MAP Kinase Kinase 4/metabolism , PPAR gamma/physiology , Prostaglandin D2/analogs & derivatives , Proto-Oncogene Proteins c-akt/metabolism , Antioxidants/pharmacology , Blotting, Western , Carcinoma, Renal Cell/enzymology , Carcinoma, Renal Cell/pathology , Cell Line, Tumor , Fluorometry , Humans , Kidney Neoplasms/enzymology , Kidney Neoplasms/pathology , L-Lactate Dehydrogenase/metabolism , Microscopy, Fluorescence , Prostaglandin D2/toxicity , Reactive Oxygen Species/metabolism
11.
Sci Rep ; 2: 487, 2012.
Article in English | MEDLINE | ID: mdl-22768380

ABSTRACT

How microgravitational space environments affect aging is not well understood. We observed that, in Caenorhabditis elegans, spaceflight suppressed the formation of transgenically expressed polyglutamine aggregates, which normally accumulate with increasing age. Moreover, the inactivation of each of seven genes that were down-regulated in space extended lifespan on the ground. These genes encode proteins that are likely related to neuronal or endocrine signaling: acetylcholine receptor, acetylcholine transporter, choline acetyltransferase, rhodopsin-like receptor, glutamate-gated chloride channel, shaker family of potassium channel, and insulin-like peptide. Most of them mediated lifespan control through the key longevity-regulating transcription factors DAF-16 or SKN-1 or through dietary-restriction signaling, singly or in combination. These results suggest that aging in C. elegans is slowed through neuronal and endocrine response to space environmental cues.


Subject(s)
Caenorhabditis elegans/physiology , Gene Expression Regulation , Longevity/genetics , Space Flight , Animals , Animals, Genetically Modified , Caenorhabditis elegans/genetics , Endocrine Cells/metabolism , Male , Models, Biological , Mutation , Neurons/metabolism , Pheromones/metabolism , RNA Interference , Signal Transduction , Weightlessness
12.
PLoS One ; 6(8): e23527, 2011.
Article in English | MEDLINE | ID: mdl-21858156

ABSTRACT

BACKGROUND: One of the most important challenges in the study of aging is to discover compounds with longevity-promoting activities and to unravel their underlying mechanisms. Royal jelly (RJ) has been reported to possess diverse beneficial properties. Furthermore, protease-treated RJ (pRJ) has additional pharmacological activities. Exactly how RJ and pRJ exert these effects and which of their components are responsible for these effects are largely unknown. The evolutionarily conserved mechanisms that control longevity have been indicated. The purpose of the present study was to determine whether RJ and its related substances exert a lifespan-extending function in the nematode Caenorhabditis elegans and to gain insights into the active agents in RJ and their mechanism of action. PRINCIPAL FINDINGS: We found that both RJ and pRJ extended the lifespan of C. elegans. The lifespan-extending activity of pRJ was enhanced by Octadecyl-silica column chromatography (pRJ-Fraction 5). pRJ-Fr.5 increased the animals' lifespan in part by acting through the FOXO transcription factor DAF-16, the activation of which is known to promote longevity in C. elegans by reducing insulin/IGF-1 signaling (IIS). pRJ-Fr.5 reduced the expression of ins-9, one of the insulin-like peptide genes. Moreover, pRJ-Fr.5 and reduced IIS shared some common features in terms of their effects on gene expression, such as the up-regulation of dod-3 and the down-regulation of dod-19, dao-4 and fkb-4. 10-Hydroxy-2-decenoic acid (10-HDA), which was present at high concentrations in pRJ-Fr.5, increased lifespan independently of DAF-16 activity. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that RJ and its related substances extend lifespan in C. elegans, suggesting that RJ may contain longevity-promoting factors. Further analysis and characterization of the lifespan-extending agents in RJ and pRJ may broaden our understanding of the gene network involved in longevity regulation in diverse species and may lead to the development of nutraceutical interventions in the aging process.


Subject(s)
Aging/drug effects , Caenorhabditis elegans/drug effects , Fatty Acids/pharmacology , Longevity/drug effects , Active Transport, Cell Nucleus/drug effects , Aging/genetics , Aging/physiology , Animals , Bees/chemistry , Caenorhabditis elegans/genetics , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Cell Nucleus/metabolism , Chromatography/methods , Dose-Response Relationship, Drug , Fatty Acids/chemistry , Fatty Acids/metabolism , Fatty Acids, Monounsaturated/pharmacology , Forkhead Transcription Factors , Gene Expression Profiling , Gene Expression Regulation/drug effects , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Longevity/genetics , Longevity/physiology , Mutation , Oligonucleotide Array Sequence Analysis , Peptide Hydrolases/metabolism , Promoter Regions, Genetic/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/genetics , Transcription Factors/metabolism
13.
Geriatr Gerontol Int ; 10 Suppl 1: S59-69, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20590843

ABSTRACT

Lifespan can be lengthened by genetic and environmental modifications. Study of these might provide valuable insights into the mechanism of aging. Low doses of radiation and short-term exposure to heat and high concentrations of oxygen prolong the lifespan of the nematode Caenorhabditis elegans. These might be caused by adaptive responses to harmful environmental conditions. Single-gene mutations have been found to extend lifespan in C. elegans, Drosophila and mice. So far, the best-characterized system is the C. elegans mutant in the daf-2, insulin/IGF-I receptor gene that is the component of the insulin/IGF-I signaling pathway. The mutant animals live twice as long as the wild type. The insulin/IGF-I signaling pathway regulates the activity of DAF-16, a FOXO transcription factor. However, the unified explanation for the function of DAF-16 transcription targets in the lifespan extension is not yet fully established. As both of the Mn superoxide dismutase (MnSOD) isoforms (sod-2 and sod-3) are found to be targets of DAF-16, we attempted to assess their functions in regulating lifespan and oxidative stress responsivity. We show that the double deletions of sod-2 and sod-3 genes induced oxidative-stress sensitivity but do not shorten lifespan in the daf-2 mutant background, indicating that oxidative stress is not necessarily a limiting factor for longevity. Furthermore, the deletion in the sod-3 gene lengthens lifespan in the daf-2 mutant. We conclude that the MnSOD systems in C. elegans fine-tune the insulin/IGF-I-signaling based regulation of longevity by acting not as anti-oxidants but as physiological-redox-signaling modulators.


Subject(s)
Gene Expression Regulation/physiology , Longevity/physiology , Oxidative Stress/physiology , Adaptation, Physiological , Aging/physiology , Animals , Caenorhabditis elegans/radiation effects , Caenorhabditis elegans Proteins/physiology , Forkhead Transcription Factors , Humans , Hyperoxia , Larva , Mutation , Oligonucleotide Array Sequence Analysis , Receptor, IGF Type 1/physiology , Superoxide Dismutase/physiology , Transcription Factors/physiology
14.
Aging Cell ; 9(4): 558-69, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20477758

ABSTRACT

Trehalose is a disaccharide of glucose found in diverse organisms and is suggested to act as a stress protectant against heat, cold, desiccation, anoxia, and oxidation. Here, we demonstrate that treatment of Caenorhabditis elegans with trehalose starting from the young-adult stage extended the mean life span by over 30% without any side effects. Surprisingly, trehalose treatment starting even from the old-adult stage shortly thereafter retarded the age-associated decline in survivorship and extended the remaining life span by 60%. Demographic analyses of age-specific mortality rates revealed that trehalose extended the life span by lowering age-independent vulnerability. Moreover, trehalose increased the reproductive span and retarded the age-associated decrease in pharyngeal-pumping rate and the accumulation of lipofuscin autofluorescence. Trehalose also enhanced thermotolerance and reduced polyglutamine aggregation. These results suggest that trehalose suppressed aging by counteracting internal or external stresses that disrupt protein homeostasis. On the other hand, the life span-extending effect of trehalose was abolished in long-lived insulin/IGF-1-like receptor (daf-2) mutants. RNA interference-mediated inactivation of the trehalose-biosynthesis genes trehalose-6-phosphate synthase-1 (tps-1) and tps-2, which are known to be up-regulated in daf-2 mutants, decreased the daf-2 life span. These findings indicate that a reduction in insulin/IGF-1-like signaling extends life span, at least in part, through the aging-suppressor function of trehalose. Trehalose may be a lead compound for potential nutraceutical intervention of the aging process.


Subject(s)
Caenorhabditis elegans/drug effects , Caenorhabditis elegans/physiology , Longevity/drug effects , Trehalose/pharmacology , Adaptation, Physiological/drug effects , Animals , Caenorhabditis elegans Proteins/metabolism , Fluorescence , Lipofuscin/metabolism , Peptides/chemistry , Peptides/metabolism , Pharynx/drug effects , Pharynx/physiology , Protein Structure, Quaternary , RNA Interference/drug effects , Reproduction/drug effects , Survival Analysis , Temperature
15.
Mol Cell Biochem ; 338(1-2): 149-56, 2010 May.
Article in English | MEDLINE | ID: mdl-20020184

ABSTRACT

Pig 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 1 cDNA was cloned from neonatal pig testis, and 15 nucleotides were found to differ from the sequence in GenBank (Accession No. NM_214248). It was an exclusive clone obtained as pig 11beta-HSD type 1, and the sequence of 11beta-HSD type 1 cDNA cloned from pig liver was identical to that from testis. Amino acid sequence, deduced from cloned cDNA, also had a conserved triad of catalytically important Ser, Tyr and Lys residues for the short-chain dehydrogenase/reductase family, a membrane-spanning domain consisting of hydrophobic amino acid and a glycine motif in the cofactor binding region. The protein translated from this clone on expression in mammalian HEK293 cells exhibited oxo-reduction activity of cortisone and oxidation activity of cortisol. Furthermore, this oxo-reduction activity of cortisone was stimulated by co-expression of human H6PDH, while oxidation activity of cortisol was suppressed by H6PDH co-expression in HEK293 cells. Based on these results, the sequence of newly cloned cDNA is considered to correspond to an active enzyme form of pig 11beta-HSD type 1.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1 , DNA, Complementary , Isoenzymes , Testis/enzymology , 11-beta-Hydroxysteroid Dehydrogenase Type 1/genetics , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Amino Acid Sequence , Animals , Animals, Newborn , Base Sequence , Cells, Cultured , DNA, Complementary/genetics , DNA, Complementary/metabolism , Humans , Hydrocortisone/metabolism , Isoenzymes/genetics , Isoenzymes/metabolism , Male , Molecular Sequence Data , Sequence Alignment , Sequence Homology, Amino Acid , Swine
16.
Exp Gerontol ; 43(6): 520-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18406553

ABSTRACT

In Caenorhabditis elegans, the downregulation of insulin-like signaling induces lifespan extension (Age) and the constitutive formation of dauer larvae (Daf-c). This also causes resistance to oxidative stress (Oxr) and other stress stimuli and enhances the expression of many stress-defense-related enzymes such as Mn superoxide dismutase (SOD) that functions to remove reactive oxygen species in mitochondria. To elucidate the roles of the two isoforms of MnSOD, SOD-2 and SOD-3, in the Age, Daf-c and Oxr phenotypes, we investigated the effects of a gene knockout of MnSODs on them in the daf-2 (insulin-like receptor) mutants that lower insulin-like signaling. In our current report, we demonstrate that double deletions of two MnSOD genes induce oxidative-stress sensitivity and thus ablate Oxr, but do not abolish Age in the daf-2 mutant background. This indicates that Oxr is not the underlying cause of Age and that oxidative stress is not necessarily a limiting factor for longevity. Interestingly, deletions in the sod-2 and sod-3 genes suppressed and stimulated, respectively, both Age and Daf-c. In addition, the sod-2/sod-3 double deletions stimulated these phenotypes in a similar manner to the sod-3 deletion, suggesting that the regulatory pathway consists of two MnSOD isoforms. Furthermore, hyperoxic and hypoxic conditions affected Daf-c in the MnSOD-deleted daf-2 mutants. We thus conclude that the MnSOD systems in C. elegans fine-tune the insulin-like-signaling based regulation of both longevity and dauer formation by acting not as antioxidants but as physiological-redox-signaling modulators.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/metabolism , Gene Expression Regulation, Developmental , Longevity/physiology , Animals , Base Sequence , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Gene Deletion , Insulin/metabolism , Insulin-Like Growth Factor I/metabolism , Longevity/genetics , Metamorphosis, Biological/genetics , Molecular Sequence Data , Mutation , Oxidative Stress , Parasitology/methods , RNA Interference , Signal Transduction/genetics , Superoxide Dismutase/genetics , Superoxide Dismutase-1
17.
Mol Cell Biochem ; 309(1-2): 209-15, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17978863

ABSTRACT

Expression of the human Ke 6 gene, 17beta-hydroxysteroid dehydrogenase type 8, in E. coli and the substrate specificity of the expressed protein were examined. The tissue distribution of mRNA expression of the human Ke 6 gene was also studied using real-time PCR. Human Ke 6 gene was expressed as an enzymatically-active His-tag fusion protein, whose molecular weight was estimated to be 32.5 kDa by SDS-polyacrylamide gel electrophoresis. Expressed human Ke 6 gene effectively catalyzed the conversion of estradiol into estrone. Testosterone, 5alpha-dihydrotestosterone, and 5-androstene-3beta,17beta-diol were also catalyzed into the corresponding 17-ketosteroid at 2.4-5.9% that of estradiol oxidation. Furthermore, expressed enzyme catalyzed the reduction of estrone to estradiol, but the rate was a mere 2.3%. Human Ke 6 gene mRNA was expressed in the various tissues examined, such as brain, cerebellum, heart, lung, kidney, liver, small intestine, ovary, testis, adrenals, placenta, prostate, and stomach. Expression of human Ke 6 gene mRNA was especially abundant in prostate, placenta, and kidney. The levels in prostate and placenta were higher than that in kidney, where it is known to be expressed in large quantities.


Subject(s)
Escherichia coli/metabolism , Gene Expression Profiling , Gene Expression Regulation, Enzymologic , Oxidoreductases/genetics , Proteins/genetics , Sequence Homology, Nucleic Acid , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Female , Humans , Kinetics , Male , Mice , Middle Aged , Oxidoreductases/metabolism , Proteins/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Substrate Specificity , Time Factors
18.
Microgravity Sci Technol ; 19(5-6): 159-163, 2007 Sep.
Article in English | MEDLINE | ID: mdl-19513185

ABSTRACT

The first International Caenorhabditis elegans Experiment (ICE-First) was carried out using a Russian Soyuz spacecraft from April 19-30, 2004. This experiment was a part of the program of the DELTA (Dutch Expedition for Life science Technology and Atmospheric research) mission, and the space agencies that participate in the International Space Station (ISS) program formed international research teams. A Japanese research team that conducted by Japan aerospace Exploration Agency (JAXA) investigated the following aspects of the organism: (1) whether meiotic chromosomal dynamics and apoptosis in the germ cells were normal under microgravity conditions, (2) the effect of the space flight on muscle cell development, and (3) the effect of the space flight on protein aggregation. In this article, we summarize the results of these biochemical and molecular biological analyses.

19.
J Steroid Biochem Mol Biol ; 101(2-3): 145-50, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16890426

ABSTRACT

17beta-Hydroxysteroid dehydrogenase (17beta-HSD) Type3 is an NADPH-dependent membrane-bound enzyme that is specifically expressed in testis and catalyzes the conversion of androstenedione to testosterone. To date, the sequence of Type3 enzymes has been clarified in humans, mice and rats; however, the sequence of the pig enzyme remains unknown. In this study, we determined the cDNA sequence of pig testicular 17beta-HSD Type3. PCR primers for partial pig testicular 17beta-HSD Type3 were designed from rat and human enzyme consensus sequences. Full-length cDNA was obtained by 3'- and 5'-RACE based on partial PCR products. The cDNA coding region was 933 bp in length, which is the same as the human enzyme, and shared 84.7% sequence identity with the human cDNA coding region. The monomer was estimated to have a molecular weight of 34,855 and to contain 310 amino acid residues. The predicted pig amino acid sequence showed 81.9, 75.5 and 72.9% sequence identity with the human, rat and mouse sequences, respectively. To elucidate 17beta-HSD Type3 activity, the expression vector pCMV/pig17beta-HSD3 was established and transfected into human embryo kidney 293 cells. Subsequently, 17beta-HSD activity (androstenedione conversion to testosterone) was strongly detected in cell lysates.


Subject(s)
17-Hydroxysteroid Dehydrogenases/genetics , 17-Hydroxysteroid Dehydrogenases/metabolism , Swine/metabolism , Testis/enzymology , Amino Acid Sequence , Animals , Base Sequence , Cell Line , DNA, Complementary , Gene Expression , Humans , Male , Molecular Sequence Data , RNA, Messenger/metabolism , Transfection
20.
Biosci Biotechnol Biochem ; 69(12): 2479-81, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16377915

ABSTRACT

The nematode Caenorhabditis elegans yields a substance(s) inducing the larval diapause, called dauer-inducing pheromone. We discovered that the crude pheromone extract extends the adult lifespan in the animal. This extension does not occur in the mutant animal, in which expansion of the lifespan caused by other mutations reducing insulin signaling is suppressed. This is the first description concerning the relevancy of the pheromone to the longevity in the animal.


Subject(s)
Caenorhabditis elegans Proteins/pharmacology , Caenorhabditis elegans/growth & development , Longevity/drug effects , Pheromones/pharmacology , Aging/drug effects , Aging/physiology , Animals , Antimetabolites/pharmacology , Caenorhabditis elegans/drug effects , Floxuridine/pharmacology , Insulin/physiology , Larva , Mutation/genetics , Signal Transduction/drug effects
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