Expression levels of microRNAs that are potential cytochrome P450 regulators in cynomolgus macaques

PSTPIP2 regulates synovial macrophages polarization and dynamics via ERβ in the joint microenvironment

Background

The cytoskeletal protein, PSTPIP2, is associated with inflammation and is predominantly expressed in macrophages. Previous data have shown that PSTPIP2 inhibits articular bone damage in arthritic rats. The aim of this study is to explore the molecular mechanism of PSTPIP2’s resistance to bone erosion.

Methods

In the current study, peripheral blood and surgically excised synovial tissue from RA patients, DBA/1 mice, Pstpip2^CreR26-ZsGreen reporter mice, and Esr2^fl/fl/Adgre-Cre tool mice were used for in vivo studies. Adeno-associated viral vector was used to overexpress PSPTIP2 protein in vivo.

Results

We found that The level of PSTPIP2 in synovial macrophages is negatively correlated with RA disease activity, which is mediated by synovial macrophages polarization. PSTPIP2^hi synovial macrophages form a tight immunological barrier in the lining layer. Notably, the ability of PSTPIP2 to regulate synovial macrophages polarization is dependent on ERβ. Additionally, PSTPIP2 regulates the dynamics of synovial macrophages via ERβ.

Conclusions

Together, this study reveals that PSTPIP2 regulates synovial macrophages polarization and dynamics via ERβ to form an immunological barrier (F4/80⁺PSTPIP2^hi cell-enriched zone) for the joints. Thus, local modulation of PSTPIP2 expression in the joint microenvironment may be a potential strategy for controlling bone erosion in rheumatoid arthritis.

Graphical Abstract

PSTPIP2 regulates synovial macrophages polarization and dynamics via ERβ to form F4/80⁺PSTPIP2^hi cellular barrier in joint microenvironment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02939-y.

Ovarian Aging: Role of Pituitary-Ovarian Axis Hormones and ncRNAs in Regulating Ovarian Mitochondrial Activity

The number of mitochondria in the oocyte along with their functions (e.g., energy production, scavenger activity) decline with age progression. Such multifaceted functions support several processes during oocyte maturation, ranging from energy supply to synthesis of the steroid hormones. Hence, it is hardly surprising that their impairment has been reported in both physiological and premature ovarian aging, wherein they are crucial players in the apoptotic processes that arise in aged ovaries. In any form, ovarian aging implies the progressive damage of the mitochondrial structure and activities as regards to ovarian germ and somatic cells. The imbalance in the circulating hormones and peptides (e.g., gonadotropins, estrogens, AMH, activins, and inhibins), active along the pituitary-ovarian axis, represents the biochemical sign of ovarian aging. Despite the progress accomplished in determining the key role of the mitochondria in preserving ovarian follicular number and health, their modulation by the hormonal signalling pathways involved in ovarian aging has been poorly and randomly explored. Yet characterizing this mechanism is pivotal to molecularly define the implication of mitochondrial dysfunction in physiological and premature ovarian aging, respectively. However, it is fairly difficult considering that the pathways associated with ovarian aging might affect mitochondria directly or by altering the activity, stability and localization of proteins controlling mitochondrial dynamics and functions, either unbalancing other cellular mediators, released by the mitochondria, such as non-coding RNAs (ncRNAs). We will focus on the mitochondrial ncRNAs (i.e., mitomiRs and mtlncRNAs), that retranslocate from the mitochondria to the nucleus, as active players in aging and describe their role in the nuclear-mitochondrial crosstalk and its modulation by the pituitary-ovarian hormone dependent pathways. In this review, we will illustrate mitochondria as targets of the signaling pathways dependent on hormones and peptides active along the pituitary/ovarian axis and as transducers, with a particular focus on the molecules retrieved in the mitochondria, mainly ncRNAs. Given their regulatory function in cellular activities we propose them as potential diagnostic markers and/or therapeutic targets.