ABSTRACT
Objective:To explore the relationship between the transforming growth factor-β (TGF-β) signaling pathway and steroid-induced osteonecrosis of the femoral head in young rabbits.Methods:Sixty 8-week-old rabbits weighing 1.5-2.0 kg were randomly divided into steroid injection group (48 cases) and control group (12 cases). Rabbits in the former group were injected with Prednisolone Acetate 7.5 mg/kg into bilateral gluteal muscles twice a week for 8 weeks, and those with successful modeling were included in the disease group; otherwise, they were included in the non-disease group.Rabbits in control group were similarly injected with the same volume of 9 g/L saline.Penicillin sodium 50 000 U/rabbit was injected once a week for preventing infection.After 8 weeks of injection, CT was performed in all the experimental animals.They were then sacrificed for collecting bilateral femoral heads.Expression levels of TGF-β1, TGF-β2, Smad2 and Smad3 in the femoral head were detected by enzyme linked immunosorbent assay (ELISA), and the mRNA level of Runx2 in the femoral head was detected by quantitative real-time PCR (qPCR), the expression differences of related factors in each group were compared.Results:In steroid injection group (48 cases), 6 rabbits were sacrificed, and 32 survived, involving 6/32 cases (18.75%) experimental animals with positive avascular necrosis (disease group), and 26 negative ones (non-disease group). ELISA data showed that expression levels of TGF-β1 in control group, non-disease group and disease group were (77.12±14.62) ng/L, (90.17±11.90) ng/L and (126.14±25.66) ng/L, respectively ( t=3.35, 4.24, all P<0.05). The expression levels of TGF-β2 in control group, non-disease group and disease group were (74.54±7.63) ng/L, (89.24±9.51) ng/L and (109.74±16.45) ng/L, respectively ( t=4.12, 5.65, all P<0.01). The expression levels of Smad2 in control group, non-disease group and disease group were (17.74±2.72) μg/L, (23.82±3.58) μg/L and (31.28±3.88) μg/L, respectively ( t= 4.54, 7.99, all P<0.01). The expression levels of Smad3 in control group, non-disease group and disease group were (1.76±0.52) μg/L, (2.39±0.45) μg/L and (3.53±0.47) μg/L, respectively ( t=5.60, 6.71, all P<0.01). qPCR data showed that the mRNA levels of Runx2 in control group, non-disease group and disease group were 1.02±0.17, 1.27±0.14, and 1.72±0.11, respectively ( t=7.60, 8.91, all P<0.01). Conclusions:TGF-β is up-regulated in the model of steroid-induced osteonecrosis of the femoral head in young rabbits, which stimulates the proliferation and differentiation of osteoblasts and osteoclasts, and triggers the process of bone remodeling.The TGF-β signaling pathway involved in the repair of necrotic bone.
ABSTRACT
Objective Our previous study demonstrated that toll-like receptor 2(TLR2) can distinguish extraneous antigen and prevent the immunological response. This study was designed to detect the expression of toll-like receptor 2 (TLR2) mRNA in cornea and investigate the effect of steroid on TLR2 expression in rats cornea following allograft penetrating keratoplasty. Methods The penetrating keratoplasty models were established in SPF rats with the 108 SD rats as receiptors and 36 SPF Wistar rats as donors, and other 6 SPF SD rats worked as normal controls. The receiptor rats were divided randomly into autograft group, allograft group and steriod group. The clarity and neovascularization of corneas of experiment rats were examined under the slit-lamp microscope and the rejection index was calculated based on Holland criteria. Corneal histopathological examination was carried out by hemotoxylin and eosin staining under the light microscope, and real time-PCR was employed for the detect of TLR2 mRNA in the corneas at the fifth, seventh and ninth day after operation. The experimental animals were obtained from the Animal Experimental Center of Southern Medical University and the procedure followed the Statement of Association for Research in Vision and Ophthalmology. Results The rejection occurred in 7 days after operation in allograft group, and only mild edema, opacity and neovascularization of corneas were found at different degrees in 9 days after operation in autograft group and steriod group. Severe corneal edema, a lots of inflammatory cells infiltration and new vessels in stroma were seen in allograft group, and mild inflammatory response was found in autograft group and steriod group. Normal comeal structure was exhibited in normal control group under the light microscope. The fold differences of TLR2 mRNA expression in cornea after amplification was significantly different among three groups and different time points (F_(group) = 39. 46, P = 0. 00; F_(time) =35. 38, P = 0. 00 ; F_(interaction) = 45. 66, P =0. 00), and the evident enhance of TLR2 mRNA expression was revealed in allograft group compared with autograft group (P ＜ 0. 05) and declined in steriod group (P ＜ 0. 05). Conclusion Steriod may restrain the acute allograft rejection by down-regulating the expression of TLR2 in corneas and its signals transaction. This result suggests that steriod offer a protection from rejection of cornea after penetrating keratoplasty.
ABSTRACT
Tuberculosis of the bones and joints is not an uncommon condition in Korea, but extraosseous tuberculosis of the soft tissue is relatively rare. A few reports of extraosseous tuberculosis, tuberculous tenosynovitis and bursitis, hsve been published in the literature, but there have been no reports concerning soft tissue tuberculosis in other than the tendon, synovium and bursa. We reviewed 7 cases of soft tissue tuberculosis of the lower back at the Department of Orthopedic Surgery, Yonsei University College of Medicine from Jan. 1984 to Sept. 1986. Five cases had received steroid injection to the lumbosscral region, and two had undergone acupuncture, thus all seven cases had experienced injections to the lumbosacral region. We think that a possible route of infection is the hematogenous one, at an area of decreased local resistance after steroid injection, And that direct inoculation of the tuberculous bacilli was result of artificial injection and acupuncture. But, further studies are needed to support the proposal that the hematogenous route following steroid injection and direct inoculation by artifical puncture is the source of soft tissue tuberculosis. These results indicate that steroid injections into the soft tissue should be performed limitedly under sterile conditions.