BACKGROUND: Studies have found that Sambucus sibirica Nakai can promote osteoblast
division, proliferation, and secretion of alkaline phosphatase to accelerate
bone matrix calcification, promote new bone formation, and promote the
absorption of necrotic bone.
OBJECTIVE: To observe the effects of two
extracts of Xinjiang Sambucus sibirica Nakai bark in promoting fracture healing
in rats.
METHODS: A total of 108 male Sprague-Dawley
rats, 3 months old, were randomly divided into sham-operated group, model
group, Zhong Hua Die Da Wan group (0.54 g/kg, negative control group), high-,
middle- and low-dose ethanol extract groups (0.314, 0.157, 0.078 g/kg), high-,
middle, and low-dose water extract groups (0.340, 0.170, 0.085 g/kg). Except for
the sham-operated group, the middle segment of the femoral shaft was cut off to
make a model of open femoral fracture. In the sham-operated group, only the
femoral shaft was exposed and no osteotomy was performed. Intragastric
administration began at 1 day after modeling and continued for 6 weeks (1
time/day). At 2, 4, 6 weeks after modeling, the effects of two extracts of
Sambucus sibirica Nakai bark on serum-related biochemical indicators, X-ray
imaging, biomechanical indicators and hematoxylin-eosin staining were observed.
RESULTS AND CONCLUSION: (1) Serum biochemical
indicators: The serum calcium level of the high-dose ethanol extract group in
each phase was lower than that of the sham-operated group and the model group,
indicating that a faster osteogenesis in the high-dose ethanol extract group,
followed by middle-dose ethanol extract group, low-dose ethanol extract group,
and high-dose water extract group. The serum phosphorus level of ethanol
extract groups was higher than that of sham-operated group, model group, and Zhong Hua Die Da Wan group; the serum
alkaline phosphatase level of high-dose ethanol extract group at each stage was
significantly higher than the other groups, indicating that a stronger
osteoblast activity in the high-dose ethanol extract group, followed by the
high-dose water extract group. (2) X-ray film: Fracture healing was significant
in the high-dose ethanol extract group, fair in the Zhong Hua Die Da Wan group, high-dose water extract, middle-dose
water extract group, middle-dose ethanol extract group, and poor in the
low-dose ethanol extract group and low-dose water extract group. (3) Three-point
bending test: At 6 weeks, the maximum load and maximum deflection of the femurs
of the two extract groups were higher than those in the model group. The
maximum load and maximum deflection of the femurs increased significantly in
the high-dose ethanol extract group followed by the high-dose water extract
group, middle-dose water extract group and middle-dose ethanol extract group.
(4) Hematoxylin-eosin staining: Fibrous epiphysis gradually formed in the
fracture area, and the bone marrow cavity was communicated. Bone healing was
better in the high-dose ethanol extract and high-dose water extract groups than
in the other groups. To conclude, these two extracts of Xinjiang Sambucus
sibirica Nakai bark are capable of improving fracture healing. Moreover,
different extraction methods and dosages of Sambucus sibirica Nakai bark
demonstrate various effects on fracture healing. Compared with water extracts,
ethanol extracts are better to promote fracture healing, and high-dose extracts
have better effects than middle- and low-dose extracts.