ABSTRACT
Bone homeostasis is a relative balance between bone formation and resorption. Signal transducer and activator of transcription 3 (STAT3), which is closely related to bone homeostasis, takes part in multiple intracellular and extracellular signal pathways. STAT3 participates in the process of osteoblast differentiation regulated by several factors. It can also maintain bone homeostasis by regulating the recruitment, differentiation and activation of osteoclasts. In addition, STAT3 is involved in the interaction between osteoblasts and osteoclasts. Patients with STAT3 mutations can have several inherited bone metabolism diseases. Furthermore, STAT3 plays a critical role in load-driven bone remodeling. Mechanical stimulation promotes osteoblast differentiation and bone formation through activating or enhancing STAT3 expression during bone remodeling process. This review summarizes the participation of STAT3 in maintaining bone homeostasis together with its possible mechanisms and discusses the connection between STAT3 and mechanical stimulation in bone remodeling, so as to provide a potential pharmacological target for the treatment of bone diseases.
ABSTRACT
Objective:To investigate the prevalence, risk factors and outcomes of diastasis recti abdominis (DRA) in multiparas after the second delivery.Methods:From June 2017 to September 2019, 300 multiparas with an average age of (31.7±4.0) years (26 to 43 years) after the second delivery were recruited at 6 weeks postpartum from two hospitals in Wenzhou. There were 171 multiparas with two natural births,36 multiparas with one natural birth and one caesarean delivery, and 93 multiparas with two caesarean deliveries. The interrectus distance (IRD) was measured with palpation at 6 weeks, 6 months and 12 months after delivery. Data on age, height, weight before pregnancy and delivery, baby′s birth weight, abdominal circumference before pregnancy and delivery, fetus number, delivery mode and occupation type were collected. Strength and endurance of abdominal muscle was assessed using manual muscle testing and curl-ups, low back pain was assessed using Oswestry disability index(ODI), urinary incontinence was assessed with International Consultation on Incontinence guestionnaire-incontinentia urinae (ICIQ-UI) short form (ICIQ-SF), and quality of life was assessed using 36-item short form health survey (SF-36).Results:Prevalence of DRA was 51.7%(155/300), 39.3%(116/295) and 27.7%(80/289) 6 weeks, 6 months and 12 months after delivery, respectively. Logistic regression analysis indicated that age ( OR=1.39, 95 %CI:1.02-1.91, P=0.38), abdominal circumference ratio ( OR=2.31, 95 %CI:1.23-4.33, P=0.01), twins ( OR=11.41, 95 %CI:2.15-60.76, P<0.01), and cesarean section ( OR=1.44, 95 %CI:1.06-1.95, P=0.02) were the risk factors of DRA at 12 months after delivery. At 12 months after delivery, the multiparas with DRA had weaker strength and endurance of abdominal muscle ( Z=-3.62, P<0.01; Z=-8.91, P<0.01), more serious low back pain ( Z=-2.10, P=0.04), and lower quality of life on physical health ( t=-3.34, P<0.01) than the multiparas without DRA. No difference in prevalence and severity of urinary incontinence and quality of life on psychological health was found when comparing multiparas with and without DRA (χ 2=0.66, P=0.42; Z=-1.18, P=0.24; t=0.91, P=0.36). Conclusion:Multipara after the second delivery has great likelihood for DRA.Age, abdominal circumference ratio, twins, and cesarean section are the risk factors of DRA. DRA is related to abdominal muscle dysfunction, low back pain, and quality of life.