Mesenchymal stem cells in fibrotic diseases-the two sides of the same coin.

Fibrosis is caused by extensive deposition of extracellular matrix (ECM) components, which play a crucial role in injury repair. Fibrosis attributes to ~45% of all deaths worldwide. The molecular pathology of different fibrotic diseases varies, and a number of bioactive factors are involved in the pathogenic process. Mesenchymal stem cells (MSCs) are a type of multipotent stem cells that have promising therapeutic effects in the treatment of different diseases. Current updates of fibrotic pathogenesis reveal that residential MSCs may differentiate into myofibroblasts which lead to the fibrosis development. However, preclinical and clinical trials with autologous or allogeneic MSCs infusion demonstrate that MSCs can relieve the fibrotic diseases by modulating inflammation, regenerating damaged tissues, remodeling the ECMs, and modulating the death of stressed cells after implantation. A variety of animal models were developed to study the mechanisms behind different fibrotic tissues and test the preclinical efficacy of MSC therapy in these diseases. Furthermore, MSCs have been used for treating liver cirrhosis and pulmonary fibrosis patients in several clinical trials, leading to satisfactory clinical efficacy without severe adverse events. This review discusses the two opposite roles of residential MSCs and external MSCs in fibrotic diseases, and summarizes the current perspective of therapeutic mechanism of MSCs in fibrosis, through both laboratory study and clinical trials.

[Follow-up of discectomy with transforaminal endoscope through interlaminar approach for lumbar disc herniation].

OBJECTIVE: To evaluate the outcomes of discectomy with transforaminal endoscope through interlaminar approach in treating lumbar disc herniation. METHODS: From April 2009 to April 2010, the clinical data of 27 patients with lumbar disc herniation were retrospectively analyzed. The patients were treated with discectomy by transforaminal endoscope through interlaminar approach, including 20 males and 7 females, with an average age of 41.8 years, ranging from 21 to 69 year; of them, 12 patients with "from inside to outside" approach and 17 patients with "from outside to inside" approach. All the patients were followed up. Clinical effect were evaluated according to Oswestry Disability Index (ODI) and modified MacNab standard. RESULTS: The operation of one case was stopped because of unobvious visual field of bleeding and the one case was transferred to microendoscopic discectomy. Other operations of 25 cases were successful. Among 27 patients, 20 cases were followed up from 12 to 24 months with an average of (18.0+/-2.5) months. The mean of ODI improved from preoperative (75.4+/-7.8)% to (13.0+/-20.5)% at final follow-up (P=0.000). According to modified MacNab standard, 7 cases obtained excellent result, 9 good, 1 fair and 3 poor. Among the poor outcome, one patient accepted the classical discectomy because of recurrent herniation of same level three months later,and the other two need take medicine. CONCLUSION: The discectomy with transforaminal endoscope through interlaminar approach for lumbar disc herniation is effective by decompress through from outside to inside access and from inside to outside access,the former is recommended to the dural sac and nerve root compressed to collateral side by huge protrusion and the latter is recommended to relatively smaller protrusion with long time conservative therapy.