To investigate the molecular mechanism of hydroxycamptothecin (HCPT)-mediated anti-hepatic fibrosis by evaluting its effects on expression of tumor growth factor-beta 1 (TGFb1), alpha-smooth muscle actin (a-SMA) and collagen I (Col I) in hepatic satellite cells (HSCs). Cultured HSCs were treated with different concentrations of HCPT: low-dose group, 0.25 mg/L; middle-dose group, 0.5 mg/L; high-dose group, 0.75 mg/L; and control group, 0 mg/L. Cell proliferation was assessed by the MTT assay. The mRNA expressions of TGFb1, a-SMA and Col I were determined by reverse transcription-polymerase chain reaction. The protein expressions of TGFb1 and a-SMA were detected by Western blot. The content of Col I in the cultured HSCs' supernatant was measured by enzyme-linked immunosorbent assay. The MTT absorbance values of the low-dose group (0.631+/-0.074), middle-dose group (0.469+/- 0.012) and high-dose group (0.204+/- 0.001) were significantly lower than that of the control group (0.793+/-0.098; F = 82.86, P less than 0.01). Compared with the control group, the HCPT-treated groups showed significantly down-regulated gene expressions of TGFb1 (control: 0.716+/-0.064 vs. low: 0.611+/-0.040, middle: 0.510+/-0.014, high: 0.403+/-0.026), a-SMA (control: 0.696+/-0.075 vs. low: 0.579+/-0.037, middle: 0.470+/-0.024, high: 0.299+/-0.017), and Col I (control: 1.019+/-0.056 vs. low: 0.835+/-0.022, middle: 0.696+/-0.055, high: 0.322+/-0.104) (all, P less than 0.01). Meanwhile, HCPT-treated HSCs showed significantly reduced protein expressions of TGFb1 (control: 0.872+/-0.053 vs. low: 0.654+/-0.047, middle: 0.545+/-0.042, high: 0.436+/-0.039) and a-SMA (control: 0.858+/-0.050 vs. low: 0.620+/-0.045, middle: 0.525+/-0.042, high: 0.434+/-0.052) (all, P less than 0.01). The Col I levels secreted by HSCs were significantly lower in the HCPT-treated groups (low: 168.367+/-16.453 ng/ml; middle: 141.284+/-11.731 ng/ml; high: 132.910+/-10.048 ng/ml) than in the control group (188.733 +/-18.299 ng/ml) (all, P less than 0.01). The mechanism of HCPT-mediated anti-hepatic fibrosis may involve down-regulation of TGFb1 expression to inhibit HSC proliferation and activation, as well as reduction of Col I synthesis and secretion.
Actins ; metabolism ; Animals ; Camptothecin ; analogs & derivatives ; pharmacology ; Cell Proliferation ; Cells, Cultured ; Collagen Type I ; metabolism ; Hepatic Stellate Cells ; cytology ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; metabolism

Objective: To examine the effect of posterior atlanto-axial intraarticular distraction technique as revision surgery for failed posterior fossa decompression in patients with basilar invagination(BI) and atlanto-axial dislocation(AAD). Methods: The clinical data of 13 cases of AAD accompanied with BI treated at Department of Neurosurgery, Xuanwu Hospital, Capital Medical University were retrospectively analyzed. There were 3 males and 10 females,aged (42.6±9.5) years (range:30 to 63 years). All cases had assimilation of atlas and once underwent posterior fossa decompression. Anterior tissue was released through posterior approach followed by cage implantation into facet joint and occipital-cervical fixation with cantilever technique. The clinical results were evaluated using Japanese Orthopedic Association scale(JOA) and the main radiological measurements including atlantodental interval (ADI), the distance of odontoid tip above Chamberlain line(DCL),clivus-canal angle(CCA) and the length of syrinx were collected. Paired sample t test was used to compared the data before and after operation. Results: All patients underwent surgery successfully, the mean surgical time was (187.7±47.4) minutes (range from 116 to 261 minutes). Twenty occipital condyle screws, 26 C2 pedicle screws and 3 occipital plates were implanted. Clinical symptoms improved in all patients. Twelve patients had complete reduction of basilar invagination and atlanto-axial dislocation, 1 achieved near completely reduction of basilar invagination. The postoperative ADI, DCL and CCA significantly improved((4.3±1.1) mm vs. (1.8±0.8) mm, (11.7±5.0) mm vs. (6.4±2.8) mm, (142.4±7.9)° vs. (133.3±7.9)°, all P<0.01).There were 5 cases with syringomyelia before surgery, and shrinkage of syrinx was observed 1 week after surgery in all cases. Eight patients achieved bone fusion 3 months after surgery, all patients achieved bone fusion 6 months after surgery. The JOA score increased from 12.8±2.3 before surgery to 14.8±1.3 one year after surgery, with statistically significant difference (t=4.416, P<0.01).No implant failure, spacer subsidence and infection were observed. Conclusion: In cases of failure posterior fossa decompression of basilar invagination and atlanto-axial dislocation, using posterior atlanto-axial intraarticular distraction and cantilever technique with cage implantation could achieve complete reduction and symptomatic relief.
Atlanto-Axial Joint/surgery* ; Female ; Humans ; Joint Dislocations/surgery* ; Male ; Pedicle Screws ; Platybasia/surgery* ; Reoperation ; Retrospective Studies ; Spinal Fusion/methods*