BACKGROUND:The previous study of the research group confirmed that Bushen Zhuangjin Decoction can regulate bone metabolism and play an anti-osteoporosis role,and nanocrystalline collagen-based bone can assist in the repair of limb bone defects.OBJECTIVE:To explore the repair effect of nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction on osteoporotic bone defects.METHODS:Totally 84 female SD rats were randomly divided into a sham operation group(n=6,no modeling)and a bilateral ovariectomy group(n=78).After 12 weeks of bilateral ovariectomy,the sham operation group(n=6)and the bilateral ovariectomy group(n=6)were selected for osteoporosis modeling verification.The remaining 72 rats in the bilateral ovariectomy group were randomly divided into 6 intervention groups,with 12 rats in each group:groups A-E had femoral defect models(diameter 3.5 mm,depth 4 mm)established 12 weeks after bilateral ovariectomy.Group A was given double distilled water by gavage(once a day)after surgery;group B was given Bushen Zhuangjin Decoction by gavage(once a day)after surgery;group C had nanocrystalline collagen-based bone filled in the bone defect and then given double distilled water by gavage(once a day);group D had nanocrystalline collagen-based bone filled in the bone defect and then given alendronate sodium by gavage(once a week);group E had nanocrystalline collagen-based bone filled in the bone defect and then given Bushen Zhuangjin Decoction by gavage(once a day);group F had femoral defect models established at the same time after bilateral ovariectomy,and bone defect sites were filled with nanocrystalline collagen-based bone and then given Bushen Zhuangjin Decoction by gavage(once a day).All drugs were given continuously for 12 weeks.12 hours after the last administration,serum levels of type Ⅰ procollagen amino-terminal propeptide,type Ⅰ collagen cross-linked C-terminal peptide,and estradiol were detected;bone volume in the bone defect area was detected by Micro-CT.The expression of type Ⅰ collagen and vascular endothelial growth factor in the bone defect area was detected by immunohistochemical staining.RESULTS AND CONCLUSION:(1)Compared with group A,the serum level of type Ⅰ procollagen amino-terminal propeptide in groups D and E was decreased(P＜0.05).Compared with groups A and C,the serum estradiol level in groups D,E,and F was increased(P＜0.05).There was no significant difference in the bone volume in the defect area between groups A-F(P＞0.05).(2)Immunohistochemical staining showed that compared with group A,the expression of typeⅠ collagen and vascular endothelial growth factor in groups B,D,and E increased(P＜0.05).Compared with group C,the expression of type Ⅰ collagen in groups B,D,E,and F increased(P＜0.05),and the expression of vascular endothelial growth factor in groups D,E,and F increased(P＜0.05).(3)The results show that nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction may have the potential to repair bone defects in ovariectomized osteoporotic rats.

BACKGROUND:The previous study of the research group confirmed that Bushen Zhuangjin Decoction can regulate bone metabolism and play an anti-osteoporosis role,and nanocrystalline collagen-based bone can assist in the repair of limb bone defects.OBJECTIVE:To explore the repair effect of nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction on osteoporotic bone defects.METHODS:Totally 84 female SD rats were randomly divided into a sham operation group(n=6,no modeling)and a bilateral ovariectomy group(n=78).After 12 weeks of bilateral ovariectomy,the sham operation group(n=6)and the bilateral ovariectomy group(n=6)were selected for osteoporosis modeling verification.The remaining 72 rats in the bilateral ovariectomy group were randomly divided into 6 intervention groups,with 12 rats in each group:groups A-E had femoral defect models(diameter 3.5 mm,depth 4 mm)established 12 weeks after bilateral ovariectomy.Group A was given double distilled water by gavage(once a day)after surgery;group B was given Bushen Zhuangjin Decoction by gavage(once a day)after surgery;group C had nanocrystalline collagen-based bone filled in the bone defect and then given double distilled water by gavage(once a day);group D had nanocrystalline collagen-based bone filled in the bone defect and then given alendronate sodium by gavage(once a week);group E had nanocrystalline collagen-based bone filled in the bone defect and then given Bushen Zhuangjin Decoction by gavage(once a day);group F had femoral defect models established at the same time after bilateral ovariectomy,and bone defect sites were filled with nanocrystalline collagen-based bone and then given Bushen Zhuangjin Decoction by gavage(once a day).All drugs were given continuously for 12 weeks.12 hours after the last administration,serum levels of type Ⅰ procollagen amino-terminal propeptide,type Ⅰ collagen cross-linked C-terminal peptide,and estradiol were detected;bone volume in the bone defect area was detected by Micro-CT.The expression of type Ⅰ collagen and vascular endothelial growth factor in the bone defect area was detected by immunohistochemical staining.RESULTS AND CONCLUSION:(1)Compared with group A,the serum level of type Ⅰ procollagen amino-terminal propeptide in groups D and E was decreased(P＜0.05).Compared with groups A and C,the serum estradiol level in groups D,E,and F was increased(P＜0.05).There was no significant difference in the bone volume in the defect area between groups A-F(P＞0.05).(2)Immunohistochemical staining showed that compared with group A,the expression of typeⅠ collagen and vascular endothelial growth factor in groups B,D,and E increased(P＜0.05).Compared with group C,the expression of type Ⅰ collagen in groups B,D,E,and F increased(P＜0.05),and the expression of vascular endothelial growth factor in groups D,E,and F increased(P＜0.05).(3)The results show that nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction may have the potential to repair bone defects in ovariectomized osteoporotic rats.

Objective To examine the anti-central-fatigue function of maca and its underlying mechanism.Methods Forty Sprague-Dawley rats were divided randomly into a negative control group,model control group,and low-,medium-,and high-dose maca groups(0.6,1.2,and 2.4 g/kg·body weight).Rats in all groups except the negative control group were subjected to multi-factor stimulation,including cold-water swimming,sleep deprivation,restraining,and tail-clamping,to establish central fatigue rat models.Rats in the low-,medium-,and high-dose maca groups received 0.6,1.2,or 2.4 g/kg maca,respectively,by gavage for 35 days.Behavioral testing was carried out using the Morris water-maze,sucrose-preference,and tail-suspension tests.Markers of oxidative stress in the hippocampus,including superoxide dismutase(SOD),malondialdehyde(MDA),and catalase(CAT),were detected using test kits.Proteins connected with the AMP-activated protein kinase(AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)signaling pathway in the hippocampus were detected by Western blot.Results Rats in the low-,medium-,and high-dose maca groups spent significantly more time in the target quadrant compared with the model control group(P＜0.05 or P＜0.01),but there was no significant dose-effect relationship.Rats in the medium-and high-dose maca groups showed decreased escape latency(P＜0.05),increased time crossing the platform location(P＜0.05),increased sucrose preference(P＜0.05),decreased tail suspension time(P＜0.05),increased the activities of CAT(P＜0.01)and SOD(P＜0.05),and decreased MDA content(P＜0.01).Rats in the low-,medium-,and high-dose maca groups also showed significantly increased protein expression levels of AMPK and nuclear respiratory factor 1(P＜0.01 or P＜0.05),but no significant dose-effect relationship was observed.Rats in the medium-and high-dose maca groups showed increased protein expression of PGC-1α(P＜0.05 or P＜0.01),and rats in the high-dose maca group showed increased protein expression of SIRT1 and mitochondrial transcription factor A(P＜0.05 or P＜0.01).Conclusions Maca can improve the indicators of central fatigue in rats,determined by behavioral testing and oxidative stress-related factors.The underlying mechanism may be related to its regulatory effects on the AMPK/SIRT1/PGC-1α signaling pathway.

Objective To examine the anti-central-fatigue function of maca and its underlying mechanism.Methods Forty Sprague-Dawley rats were divided randomly into a negative control group,model control group,and low-,medium-,and high-dose maca groups(0.6,1.2,and 2.4 g/kg·body weight).Rats in all groups except the negative control group were subjected to multi-factor stimulation,including cold-water swimming,sleep deprivation,restraining,and tail-clamping,to establish central fatigue rat models.Rats in the low-,medium-,and high-dose maca groups received 0.6,1.2,or 2.4 g/kg maca,respectively,by gavage for 35 days.Behavioral testing was carried out using the Morris water-maze,sucrose-preference,and tail-suspension tests.Markers of oxidative stress in the hippocampus,including superoxide dismutase(SOD),malondialdehyde(MDA),and catalase(CAT),were detected using test kits.Proteins connected with the AMP-activated protein kinase(AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)signaling pathway in the hippocampus were detected by Western blot.Results Rats in the low-,medium-,and high-dose maca groups spent significantly more time in the target quadrant compared with the model control group(P＜0.05 or P＜0.01),but there was no significant dose-effect relationship.Rats in the medium-and high-dose maca groups showed decreased escape latency(P＜0.05),increased time crossing the platform location(P＜0.05),increased sucrose preference(P＜0.05),decreased tail suspension time(P＜0.05),increased the activities of CAT(P＜0.01)and SOD(P＜0.05),and decreased MDA content(P＜0.01).Rats in the low-,medium-,and high-dose maca groups also showed significantly increased protein expression levels of AMPK and nuclear respiratory factor 1(P＜0.01 or P＜0.05),but no significant dose-effect relationship was observed.Rats in the medium-and high-dose maca groups showed increased protein expression of PGC-1α(P＜0.05 or P＜0.01),and rats in the high-dose maca group showed increased protein expression of SIRT1 and mitochondrial transcription factor A(P＜0.05 or P＜0.01).Conclusions Maca can improve the indicators of central fatigue in rats,determined by behavioral testing and oxidative stress-related factors.The underlying mechanism may be related to its regulatory effects on the AMPK/SIRT1/PGC-1α signaling pathway.

BACKGROUND:The repair and clinical outcome of bone defects remains a hot and difficult area of clinical research,which is a common problem that plagues clinicians.Constructing suitable,reproducible and infinitely close to clinical animal experimental models and their scientific evaluation are essential for further clinical treatment of related diseases. OBJECTIVE:To retrospectively analyze the preparation methods and characteristics of common animal models of femoral bone defects and to assess their strengths and weaknesses,thereby providing some reference for relevant researchers to select appropriate animal models of femoral bone defects. METHODS:PubMed,Web of Science,Medline,and CNKI were retrieved for relevant literature published from January 1,2000 to August 1,2022.The keywords were"bone defect,bone,bones,defect,defects,defective,animal model,animal,model,laboratory,laboratory animal,animal laboratory"in English and"bone defect,animal model,experiment"in Chinese. RESULTS AND CONCLUSION:Twenty-seven randomized controlled animal experiments involving rats,mice,New Zealand rabbits,and sheep were included,analyzed and assessed.The most common types of bone defects were cylindrical bone defects and segmental osteotomy bone defects,generally found in the middle and distal femur.These models are mostly used to evaluate the effects of bone repair materials,drugs,drug-loaded active substances and physical therapy on bone defect repair and explore defect healing mechanisms,particularly the weight-bearing bone defect repair mechanism.Different defect kinds and femoral bone defect ranges have been found in different animal experiments.Researchers can select the suitable animal model and bone defect type based on the goal of the experiment and then set an acceptable bone defect value.Current studies have shown that cylindrical and segmental osteotomy-induced bone defects,mainly in the distal and middle femur,are mostly used in the animal models of femoral bone defects and that the surgical methods and postoperative management are more mature and operable to provide mature experimental animal models.In terms of cylindrical bone defects,rats and New Zealand rabbits are more suitable,whereas segmental osteotomy has no special requirements and all types of animals can meet the experimental requirements.