AACE	American Association of Clinical Endocrinologists
ALF	Alfacalcidol
ALP	Alkaline phosphatase
AO	Antioxidants
ARED	Advanced resistive exercise device
BP	Bisphosphonate
BF	Bone formation
BL	Bone loss
BR/BRS	Bone resorption
BMD	Bone mineral density
BT	Bone turnover
bMSC	Bone mesenchymal stem cell
BV/TV	Bone volume fraction
CM	Countermeasure
CMS	Cyclic mechanical stretch treated bone mesenchymal stem cell-derived exosomes
DM	Differentiation marker
HLU	Hindlimb unloading
IL-6 mAb	Interleukin-6 monoclonal antibody
ISS	International Space Station
MP	Menopausal
OB	Osteoblast
OC	Osteoclast
OP	Osteoporosis
PC-I	Pan-caspase inhibitor
PI	Proteasome inhibitor
PMP	Postmenopausal
PTH	Parathyroid hormone
RANKL	Receptor activator of nuclear factor κβ ligand
RHLI	Right hindlimb immobilization
R-irisin	Recombinant irisin
SCHN	Strontium-containing hydroxyapatite nanoparticles
SERM	Selective estrogen receptor modulator
S-µg	Simulated microgravity
uCaV	Urinary calcium excretion
uNTx	Urinary N-telopeptide
Wnt	Wingless-related integration site
ZOL	Zoledronic acid
µg	Microgravity