Silencing of miR-483-5p alleviates postmenopausal osteoporosis by targeting SATB2 and PI3K/AKT pathway

Fujiang Zhao1, Yier Xu2, Yulong Ouyang3

  • 1Department of Orthopaedics, Taizhou Central Hospital (Taizhou University Hospital), Taizhou 318000, China.

Aging
|February 23, 2021
PubMed

Insights

MicroRNA-483-5p (miR-483-5p) exacerbates postmenopausal osteoporosis by suppressing SATB2 and activating PI3K/AKT signaling. Inhibiting miR-483-5p shows therapeutic potential for osteoporosis.

Area of Science:

  • Molecular Biology
  • Endocrinology
  • Biochemistry

Background:

  • Postmenopausal osteoporosis (PMOP) is a significant global health concern with insufficient molecular insights and therapeutic strategies.
  • Emerging evidence implicates microRNA-483-5p (miR-483-5p) in the pathogenesis of osteoporosis.

Purpose of the Study:

  • To elucidate the role and underlying molecular mechanism of miR-483-5p in postmenopausal osteoporosis.
  • To investigate the regulatory relationship between miR-483-5p, SATB2, and the PI3K/AKT signaling pathway in PMOP.

Main Methods:

  • Analysis of miR-483-5p and SATB2 expression in PMOP patients.
  • Luciferase reporter assay to confirm SATB2 as a direct target of miR-483-5p.
  • In vitro studies using MC3T3-E1 cells and in vivo studies in ovariectomized (OVX) rat models.

Main Results:

  • miR-483-5p was upregulated and SATB2 downregulated in PMOP patients.
  • miR-483-5p mimic inhibited cell viability and osteogenic markers (OPG, RUNX2, BMP2), while miR-483-5p inhibitor, SATB2 overexpression, or PI3K/AKT inhibition reversed these effects.
  • miR-483-5p activated PI3K/AKT signaling, which was inhibited by miR-483-5p inhibitor, Lv-SATB2, or LY294002.
  • In vivo, miR-483-5p inhibitor improved bone mineral density and biomechanical parameters in OVX rats by targeting SATB2.

Conclusions:

  • miR-483-5p promotes PMOP pathogenesis by inhibiting SATB2 and activating the PI3K/AKT pathway.
  • The miR-483-5p/SATB2 axis represents a potential therapeutic target for postmenopausal osteoporosis.

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