scholarly journals The progesterone antagonist mifepristone/RU486 blocks the negative effect on life span caused by mating in female Drosophila

Aging ◽  
2015 ◽  
Vol 7 (1) ◽  
pp. 53-69 ◽  
Author(s):  
Gary N. Landis ◽  
Matthew P. Salomon ◽  
Daniel Keroles ◽  
Nicholas Brookes ◽  
Troy Sekimura ◽  
...  
Keyword(s):  
Life Span ◽  
Negative Effect ◽  
Progesterone Antagonist

Ambient temperature influences adult size and life span in jumbo squid (Dosidicus gigas)

2015 ◽  
Vol 72 (3) ◽  
pp. 400-409 ◽  
Author(s):  
Alexander Arkhipkin ◽  
Juan Argüelles ◽  
Zhanna Shcherbich ◽  
Carmen Yamashiro
Keyword(s):  
Life Cycle ◽  
Life Span ◽  
World Ocean ◽  
Sudden Increase ◽  
Adult Size ◽  
Dosidicus Gigas ◽  
Early Maturation ◽  
Jumbo Squid ◽  
Size Groups ◽  
Negative Effect

The eastern Pacific jumbo squid (Dosidicus gigas) is one of the largest and most abundant squid of the world ocean. To reveal possible interannual variability in the life span, statoliths were used to determine the age of mature females belonging to two modal size groups (<490 and >500 mm mantle length) collected before (1991–1996), during (1997–1998), and after (1999–2011) a strong El Niño event in Peruvian waters. We found that water temperatures encountered between the third and sixth months of ontogenesis had the strongest negative effect on age. Together with a weaker but significant negative effect of temperatures encountered during early life (first to third months) and later ontogenesis (seventh and eighth months), these temperature parameters (along with other environmental factors) were important in determining whether a given animal had a 1-year life cycle (early maturation and small size) or a 1.5- to 2-year life cycle (delayed maturation and large size). The possible cause of a sudden increase in abundance of large D. gigas in 2000–2001 is discussed.

scholarly journals Time-Dependent Effects of Relational Composition on the Success of Online Wellness Challenge Groups

2020 ◽  
Vol 25 (2) ◽  
pp. 147-162
Author(s):  
Jingbo Meng ◽  
Soo Yun Shin ◽  
Arram Bae ◽  
Brandon Van Der Heide
Keyword(s):  
Life Span ◽  
Time Dependent ◽  
Online Relationships ◽  
Positive Health ◽  
Online Groups ◽  
Multiple Group ◽  
Negative Effect ◽  
Group Members ◽  
Group Success ◽  
Positive Effect

Abstract This study aims to examine time-dependent effects of group-level relational composition, including the number and cohesion of prior online relationships and multiple-group membership (MGM), on the success of online wellness challenge groups (OWCGs) in promoting positive health behavior among group members. Bridging literature on online groups and social networks for health, this study collected data on 1,252 OWCGs and conducted analyses on how relational composition affected group success longitudinally over the life span of the OWCGs. The results showed that the number of prior online relationships within a group had a positive but decreasing effect over time on group success, whereas cohesion was not a significant predictor. MGM, indicating members' concurrent participation in multiple OWCGs, showed a positive effect on group success at the beginning but a negative effect towards the end of a group's life span. Theoretical and practical implications for designing successful OWCGs were discussed.

scholarly journals Metabolic Signatures of Life Span Regulated by Mating, Sex Peptide, and Mifepristone/RU486 in Female Drosophila melanogaster

2020 ◽  
Author(s):  
Gary N Landis ◽  
Devon V Doherty ◽  
Chia-An Yen ◽  
Lu Wang ◽  
Yang Fan ◽  
...  
Keyword(s):  
Life Span ◽  
Regulation Of Gene Expression ◽  
Breakdown Product ◽  
Metabolomics Data ◽  
Transgenic Expression ◽  
Sex Peptide ◽  
Dietary Amino Acids ◽  
Negative Effect ◽  
Muscle Breakdown ◽  
The Brain

Abstract Mating and transfer of male sex peptide (SP), or transgenic expression of SP, causes inflammation and decreased life span in female Drosophila. Mifepristone rescues these effects, yielding dramatic increases in life span. Here targeted metabolomics data were integrated with further analysis of extant transcriptomic data. Each of 7 genes positively correlated with life span were expressed in the brain or eye and involved regulation of gene expression and signaling. Genes negatively correlated with life span were preferentially expressed in midgut and involved protein degradation, amino acid metabolism, and immune response. Across all conditions, life span was positively correlated with muscle breakdown product 1/3-methylhistidine and purine breakdown product urate, and negatively correlated with tryptophan breakdown product kynurenic acid, suggesting a SP-induced shift from somatic maintenance/turnover pathways to the costly production of energy and lipids from dietary amino acids. Some limited overlap was observed between genes regulated by mifepristone and genes known to be regulated by ecdysone; however, mifepristone was unable to compete with ecdysone for activation of an ecdysone-responsive transgenic reporter. In contrast, genes regulated by mifepristone were highly enriched for genes regulated by juvenile hormone (JH), and mifepristone rescued the negative effect of JH analog methoprene on life span in adult virgin females. The data indicate that mifepristone increases life span and decreases inflammation in mated females by antagonizing JH signaling downstream of male SP. Finally, mifepristone increased life span of mated, but not unmated, Caenorhabditis elegans, in 2 of 3 trials, suggesting possible evolutionary conservation of mifepristone mechanisms.

scholarly journals Analysis of the role of kynurenine metabolism in drosophila viability control at the high sugar diet influence

2020 ◽  
Vol 26 ◽  
pp. 72-76
Author(s):  
V. V. Navrotskaya ◽  
Yu. Yu. Sapota
Keyword(s):  
Life Span ◽  
Pupal Stage ◽  
Negative Influence ◽  
Kynurenine Pathway ◽  
Wild Type ◽  
Nutritive Medium ◽  
Pharmacological Inhibition ◽  
High Sugar ◽  
Negative Effect ◽  
Kynurenine Metabolism

Aim. To analyze viability and life span of drosophila at genetic and pharmacological inhibition of tryptophan-kynurenine metabolism, when cultivating on the standard nutritive medium and at a high sugar diet. Methods. Wild type stock and the stock with vermilion mutation have been used. Viability (number of individuals, mortality at the pupal stage) and median life span of imagoes have been determined. Results. High sugar diet has been found to negatively affect the viability of drosophila, leading to increased mortality at the pupal stage and decrease of males’ life span; wild-type stock is less resistant to the influence of such diet as compared with mutant stock. Berberine (an inhibitor of tryptophan dioxygenase) when added to the high sugar nutritive medium reduces the negative effect of a high sugar diet on life span of the wild-type stock: males’ life span reaches control values and in females life span is even more than in the control. Conclusions. Decrease of kynurenines content in the flies organisms (both at the genetic and pharmacological inhibition of tryptophan-kynurenine metabolism) may attenuate negative influence of the high sugar diet. Keywords: drosophila, viability, life span, kynurenine pathway of tryptophan metabolism, high sugar diet.

scholarly journals Mifepristone Increases Life Span of Virgin Female Drosophila on Regular and High-fat Diet Without Reducing Food Intake

2021 ◽  
Vol 12 ◽  
Author(s):  
Gary N. Landis ◽  
Tyler A. U. Hilsabeck ◽  
Hans S. Bell ◽  
Tal Ronnen-Oron ◽  
Lu Wang ◽  
...  
Keyword(s):  
Food Intake ◽  
Life Span ◽  
Virgin Female ◽  
Coconut Oil ◽  
High Fat ◽  
High Fat Diets ◽  
Negative Effect ◽  
Transcriptomics Data ◽  
Fat Diets ◽  
Increased Activity

Background: The synthetic steroid mifepristone is reported to have anti-obesity and anti-diabetic effects in mammals on normal and high-fat diets (HFD). We previously reported that mifepristone blocks the negative effect on life span caused by mating in female Drosophila melanogaster.Methods: Here we asked if mifepristone could protect virgin females from the life span-shortening effect of HFD. Mifepristone was assayed for effects on life span in virgin females, in repeated assays, on regular media and on media supplemented with coconut oil (HFD). The excrement quantification (EX-Q) assay was used to measure food intake of the flies after 12 days mifepristone treatment. In addition, experiments were conducted to compare the effects of mifepristone in virgin and mated females, and to identify candidate mifepristone targets and mechanisms.Results: Mifepristone increased life span of virgin females on regular media, as well as on media supplemented with either 2.5 or 5% coconut oil. Food intake was not reduced in any assay, and was significantly increased by mifepristone in half of the assays. To ask if mifepristone might rescue virgin females from all life span-shortening stresses, the oxidative stressor paraquat was tested, and mifepristone produced little to no rescue. Analysis of extant metabolomics and transcriptomics data suggested similarities between effects of mifepristone in virgin and mated females, including reduced tryptophan breakdown and similarities to dietary restriction. Bioinformatics analysis identified candidate mifepristone targets, including transcription factors Paired and Extra-extra. In addition to shortening life span, mating also causes midgut hypertrophy and activation of the lipid metabolism regulatory factor SREBP. Mifepristone blocked the increase in midgut size caused by mating, but did not detectably affect midgut size in virgins. Finally, mating increased activity of a SREBP reporter in abdominal tissues, as expected, but reporter activity was not detectably reduced by mifepristone in either mated or virgin females.Conclusion: Mifepristone increases life span of virgin females on regular and HFD without reducing food intake. Metabolomics and transcriptomics analyses suggest some similar effects of mifepristone between virgin and mated females, however reduced midgut size was observed only in mated females. The results are discussed regarding possible mifepristone mechanisms and targets.

Continuum of Care Following Sports-Related Concussion

2020 ◽  
Vol 29 (3) ◽  
pp. 1389-1403
Author(s):  
Jessica Brown ◽  
Kelly Knollman-Porter
Keyword(s):  
Young Adults ◽  
Life Span ◽  
Sports Injuries ◽  
Continuum Of Care ◽  
Medical Professional ◽  
Structured Interviews ◽  
Youth Athletes ◽  
Speech Language Pathologist ◽  
History Of ◽  
Injury Reporting

Purpose Although guidelines have changed regarding federally mandated concussion practices since their inception, little is known regarding the implementation of such guidelines and the resultant continuum of care for youth athletes participating in recreational or organized sports who incur concussions. Furthermore, data regarding the role of speech-language pathologists in the historic postconcussion care are lacking. Therefore, the purpose of this retrospective study was to investigate the experiences of young adults with history of sports-related concussion as it related to injury reporting and received follow-up care. Method Participants included 13 young adults with history of at least one sports-related concussion across their life span. We implemented a mixed-methods design to collect both quantitative and qualitative information through structured interviews. Participants reported experiencing 42 concussions across the life span—26 subsequent to sports injuries. Results Twenty-three concussions were reported to a parent or medical professional, 14 resulted in a formal diagnosis, and participants received initial medical care for only 10 of the incidents and treatment or services on only two occasions. Participants reported concussions to an athletic trainer least frequently and to parents most frequently. Participants commented that previous experience with concussion reduced the need for seeking treatment or that they were unaware treatments or supports existed postconcussion. Only one concussion incident resulted in the care from a speech-language pathologist. Conclusion The results of the study reported herein shed light on the fidelity of sports-related concussion care management across time. Subsequently, we suggest guidelines related to continuum of care from injury to individualized therapy.

Effect of progesterone antagonist mifepristone on plasma CRH in term human pregnancy

1998 ◽  
Vol 5 (1) ◽  
pp. 196A-196A
Author(s):  
J BYRNE ◽  
D WING ◽  
M FRASER ◽  
M FASSETT ◽  
A BOCKING ◽  
...  
Keyword(s):  
Human Pregnancy ◽  
Progesterone Antagonist

Tumorigenesis in High-Dose Total Body Irradiated Rhesus Monkeys--A Life Span Study

2003 ◽  
Vol 31 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Carel F. Hollander ◽  
Chris Zurcher ◽  
Johan J. Broerse
Keyword(s):  
Life Span ◽  
Rhesus Monkeys ◽  
High Dose ◽  
Life Span Study ◽  
Total Body

Social Motives Predict Loneliness During a Developmental Transition

2017 ◽  
Vol 76 (4) ◽  
pp. 145-153 ◽  
Author(s):  
Jana Nikitin ◽  
Alexandra M. Freund
Keyword(s):  
Social Relationships ◽  
Well Being ◽  
Social Avoidance ◽  
Social Approach ◽  
Social Motives ◽  
Developmental Transitions ◽  
Avoidance Motivation ◽  
Negative Effect ◽  
Low Levels

Abstract. Establishing new social relationships is important for mastering developmental transitions in young adulthood. In a 2-year longitudinal study with four measurement occasions (T1: n = 245, T2: n = 96, T3: n = 103, T4: n = 85), we investigated the role of social motives in college students’ mastery of the transition of moving out of the parental home, using loneliness as an indicator of poor adjustment to the transition. Students with strong social approach motivation reported stable and low levels of loneliness. In contrast, students with strong social avoidance motivation reported high levels of loneliness. However, this effect dissipated relatively quickly as most of the young adults adapted to the transition over a period of several weeks. The present study also provides evidence for an interaction between social approach and social avoidance motives: Social approach motives buffered the negative effect on social well-being of social avoidance motives. These results illustrate the importance of social approach and social avoidance motives and their interplay during developmental transitions.

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