[Remapping age(ing) : Additional value of an affect-based and inequality-sensitive determination of the relationship between space and age(ing)]

BACKGROUND

The study of housing and living spaces has always played a central role in sociogerontological research. For example, living environments are seen as essential influencing factors on the quality of life and personal well-being (or the lack of it) of older people. The study of the relationship between space and age(ing) is dominated by psychologically influenced environmental gerontological approaches and social area-oriented research. While environmental perspectives in gerontology focus in particular on perceptions, experiences and affects to identify the relationships between space and age(ing), social area-oriented research tends to focus on social inequalities and strategies of participation.

OBJECTIVE

The results of ecogerontological approaches to affects and social area-oriented research on social inequalities are combined by means of a praxiological approach. A relational understanding of space and age is developed, which is able to focus on affects and is also sensitive to spatial exclusions based on social inequalities and which also have an affective component. This combination enables new insights into a gerontological designation of the relationship between space and age(ing).

RESULTS AND CONCLUSION

Such a remapping of age(ing) makes it possible to formulate other research questions regarding constructions of space through age or age through space and to provide impulses for gerontological research perspectives that take the complex interplay of humans, artefacts and spatial arrangements into account and explore the consequences for individual persons and also for their living spaces.

[Aging from an intersectional perspective : Suggestions for a multidimensional conceptualization of intersectional aging research]

Even a cursory view on the debate about intersectionality reveals that this is not a coherent theory or a uniform approach to the investigation of multiple inequalities. Instead openness and ambiguity are described as central characteristics of the concept, which result from the diversity of the reference theories and the multidimensionality of the categories of difference and relationships of inequality to be examined. In this article the question as to whether an intersectional perspective can provide new insights for gerontological research is explored.

[Ambivalence, old age and agency: Meaning of age-specific ambivalence for the construction of narrative identity]

Different models of the formation of age identity explain the empirically determined difference between the chronological age and the age which is subjectively perceived by elderly people themselves. From a biographical point of view and on the basis of two maximally contrasting empirical cases, this article investigates the ways ambivalence appears in the narrations of elderly people about personal aging and the narrative strategies of coping with this experience of ambivalence. The results of the analysis indicate that the conceptualization of age identity in the different models should be seen more as descriptions of potential but not necessary forms of coping with age-specific ambivalences.

A SNP in steroid receptor coactivator-1 disrupts a GSK3β phosphorylation site and is associated with altered tamoxifen response in bone

The coregulator steroid receptor coactivator (SRC)-1 increases transcriptional activity of the estrogen receptor (ER) in a number of tissues including bone. Mice deficient in SRC-1 are osteopenic and display skeletal resistance to estrogen treatment. SRC-1 is also known to modulate effects of selective ER modulators like tamoxifen. We hypothesized that single nucleotide polymorphisms (SNP) in SRC-1 may impact estrogen and/or tamoxifen action. Because the only nonsynonymous SNP in SRC-1 (rs1804645; P1272S) is located in an activation domain, it was examined for effects on estrogen and tamoxifen action. SRC-1 P1272S showed a decreased ability to coactivate ER compared with wild-type SRC-1 in multiple cell lines. Paradoxically, SRC-1 P1272S had an increased protein half-life. The Pro to Ser change disrupts a putative glycogen synthase 3 (GSK3)β phosphorylation site that was confirmed by in vitro kinase assays. Finally, knockdown of GSK3β increased SRC-1 protein levels, mimicking the loss of phosphorylation at P1272S. These findings are similar to the GSK3β-mediated phospho-ubiquitin clock previously described for the related coregulator SRC-3. To assess the potential clinical significance of this SNP, we examined whether there was an association between SRC-1 P1272S and selective ER modulators response in bone. SRC-1 P1272S was associated with a decrease in hip and lumbar bone mineral density in women receiving tamoxifen treatment, supporting our in vitro findings for decreased ER coactivation. In summary, we have identified a functional genetic variant of SRC-1 with decreased activity, resulting, at least in part, from the loss of a GSK3β phosphorylation site, which was also associated with decreased bone mineral density in tamoxifen-treated women.

A case of premature thelarche with no central cause or genetic variants within the estrogen receptor signaling pathway

BACKGROUND

Premature thelarche is defined as breast development before 8 years of age. This is most often caused by central hormone disregulation and is accompanied by concurrent bone maturation. However, we present a case of premature thelarche with concurrent bone maturation without central hormone disregulation. Genes within the estrogen signaling pathway were examined for genetic changes which might be responsible for the clinical phenotype.

PATIENT REPORT

A girl presented with breast development from 18 months of age with undetectable serum estrogens, prepubertal serum gonadotropins, advanced growth and skeletal maturation, but no increase of uterine size, thus presenting a premature thelarche variant. Serum estrogens remained below detectable limits until she entered into an unremarkable puberty at 12.1 years of age. No abnormalities or SNPs were found in the genes tested.

CONCLUSION

We describe a case of premature thelarche which cannot be attributed to a central cause of abnormal hormone levels or to alterations in genes suspected for this phenotype. We conclude that other yet to be identified factors are involved in this unique case of premature thelarche.

A single nucleotide polymorphism in steroid receptor coactivator 1 diminishes ERa coactivation

Abstract #605

Background: Single nucleotide polymorphisms (SNPs) can contribute to alterations in treatment efficiency. The 3814C>T SNP that causes a P1272S amino acid change located in the activation domain-2 (AD2) of the steroid receptor coactivator SRC-1, has been shown to be associated with decreased bone mineral density in women undergoing tamoxifen treatment for breast cancer. It is well described that members of the SRC family are regulated by posttranslational modifications. Phosphorylation has been shown to be critical for their activity. It is known that histone-acetyl-transferase (HAT) activity of SRC proteins can be controlled through phosphorylation. The C-terminus of SRC-1 is one of the major region to be phosphorylated, possibly to perform proper HAT activity. Therefore, a change from proline to serine at position 1272 is likely to have impact on phosphorylation and subsequent HAT activity. Additionally, in silico analysis of the sequence suggests that the variant removes a potential Glycogen synthase kinase 3 (GSK3) target motif at amino acid 1275. Intriguingly, phosphorylation by GSK3 has been shown to be involved in modulating the activity and functional lifetime of another member of the SRC family, SRC-3.
 Methods: In silico analysis to identify changes in phosphorylation sites after introducing the SNP was performed using http://www.cbs.dtu.dk/services/NetPhos. Mutants P1272S, P1272A, P1272E were generated by mutagenesis using QuickChange® Site-directed Mutagenesis Kit following the manufacturer's protocol. ERE-Luciferase reporter assays were conducted in HEK293 cells to compare the ability of SRC-1 wildtype (WT), variant P1272S, and mutants P1272A or P1272E to activate ERα-mediated transcription. Protein levels were determined after immunoblotting.
 Results: Post-translational modifications, particularly in the form of phosphorylation, are critical for the activity of members from the p160 family of coactivators as described above. Thus, we examined if the introduction of P1272S induces or destroys any phosphorylation sites within SRC-1. We identified phosphorylation sites by scoring the SRC-1 protein sequence including proline (WT) versus serine (SNP). Indeed we found that a cdc2 phosphorylation site is created and a cdk5 phosphorylation site is partially destroyed when serine is present instead of proline. Using an ERE-Luciferase reporter assay in HEK293 cells, we observed a significant loss of co-activation by the variant compared to SRC-1 WT. Transfecting P1272E showed a similar decrease to P1272S in these assays, suggesting the effect of decreased coactivation might be due to the introduction of a new phosphorylation site. Interestingly, transfecting P1272A was not able to rescue the phenotype of P1272S. This finding suggests an additional role for changes in protein folding with subsequent changes in protein activity. Furthermore, immunoblotting of SRC-1 WT or P1272S after estrogen treatment revealed a stabilizing effect of SRC-1 WT but not for the SNP. This further implies that introducing this SNP results in a decreased protein level and subsequently in decreased activity after hormone treatment.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 605.