Aim: Angiotensin II is believed to play an important role in tissue repair and remodeling in lungs by the angiotensin type I (AT1) receptor via a number of potential mechanisms. However, the role of the AT1 receptor in early lung injury has not been characterized. Methods: Bleomycin-induced pulmonary fibrosis (PF) in rats was utilized to value the treatment with valsartan, an AT1 receptor antagonist, by measurement of body weight, wet weight of the left lung, hydroxyproline content, mRNA expression of collagen I/III, and the degree of fibrosis in lung tissues on d 21. Tissue injury in the early phase was assessed on d 1, 3 and 7 by apoptosis, malondialdehyde content, myeloperoxidase activity, inflammatory cell count and protein content. Angiotensin converting enzyme (ACE) activity and the AT1 receptor in lung tissues were analyzed by biochemistry method and Western blotting, respectively. Results: Valsartan ameliorated PF induced by bleomycin in the rats on d 21. After bleomycin was injected intratracheally, increases in the lung AT1 receptor and ACE activity were observed by d 1, 3 and 7. Lung injury deteriorated in the early phase. Valsartan reduced the increase of the AT1 receptor, ACE activity and lung injury induced by bleomycin in the early phase. Conclusion: These observations suggest that angiotensin II may play a potent role in early lung injury via the AT1 receptor. AT1 receptor antagonists should be assessed as potential new therapies for fibrotic lung disease.

After comparing mortality and clinical signs in rats receiving different dexamethasone treatments, we investigated whether 0.5 mg/kg/d dexamethasone could delay pulmonary fibrosis induced by bleomycin and its time course (1, 3, 7, 14, 21 and 28 days). Tissue injury was assessed by apoptosis, lactate dehydrogenase (LDH) release, malondialdehyde content, and protein content; and inflammation was measured in terms of myeloperoxidase (MPO) activity, inflammatory cell count, and the mRNA expression of pro/inflammatory cytokines. Fibrogenic activity was analyzed by measuring the mRNA expression of fibrotic cytokines in tissue, and the promotion of fibroproliferation and synthesis of collagen type I by bronchoalveolar lavage fluids in vitro; and fibrosis was assessed by measuring the hydroxyproline content and collagen-I mRNA expression, and by histology. Bleomycin treatment induced tissue injury, inflammation and fibrogenic activity in lung, and led to fibrosis. Treatment with dexamethasone diminished the extent of fibrosis by strongly reducing inflammation, lung damage, and fibrogenic activity. These results demonstrate that the progression of bleomycin-induced pulmonary fibrosis in rats can be delayed by dexamethasone treatment, which appeared to alleviate not only inflammation but also lung damage and fibrogenic activity, indicating a possible new role for dexamethasone in the treatment of fibrosis.

The document ‘Good Laboratory Practice Regulations for Nonclinical Drug Safety Studies’ issued in China on 14 October 1999 was updated by China's State Food and Drug Administration (SFDA) and became effective as of 1 September 2003. In October 2003, SFDA started to commission Good Laboratory Practice (GLP) inspections. Since then, China has adopted a national GLP conformity accreditation system, and it became increasingly required that drug safety studies in China were to be carried out in accordance with the principles of GLP regulations. Development of a standardized safety study platform also plays an important role in the strategy ‘Establishing National Drug Innovation System in Knowledge Innovation’, led by Shanghai Institute of Materia Medica (SIMM), China Academy of Sciences. Demands from outside and inside SIMM required that a GLP compliance program for drug safety studies be established at SIMM. However, the establishment of a GLP compliance program was challenging. In this article, the strategies adopted and the progress made towards meeting the challenges of establishing a GLP compliance program for drug safety studies at SIMM are described. Copyright © 2005 John Wiley & Sons, Ltd.

目的研究雷公藤衍生物XX对大鼠的长期毒性. 方法 6周龄Sprague-Dawley大鼠96只,雌雄各半,随机分为对照组(体积分数为0.2%的HPMC)和低、中、高剂量组,每组24只.雌性大鼠的剂量分别为1、2和4 mg/kg,雄性大鼠的剂量分别为2、4和8 mg/kg.

Aim: To investigate the mitochondria-initiated apoptosis pathway involved in Carbon tetrachloride (CCl 4 ) hepatotoxicity in vitro . Methods: Several cytotoxicity endpoints, including WST-8 metabolism, lactate dehydrogenase leakage and morphological changes, were examined. The 5,5′-dithio-bis(2-nitrobenzoic acid) reaction was used to measure reduced glutathione level, and the malondialdehyde level was determined using the thiobarbituric acid assay. The release of cytochrome c and Bcl-X L was detected by Western blot. Caspase-3 activity was measured using the fluorogenic substrate Ac-DEVD-AMC. DNA fragmentation was used to evaluate cell apoptosis. Results: A time-and dose-dependent decrease in cellular glutathione content was observed, along with a concomitant increase in malondialdehyde levels following the application of CCl 4 . Caspase 3 activity was stimulated at all doses of CCl 4 , with the most significant activation at 3 mmol/L. Cytochrome c was released obviously after CCl 4 treatment. A time-dependent decrease in Bcl-X L expression was observed. DNA fragmentation results revealed apoptosis and necrosis following CCl 4 treatment. Conclusion: Oxidative damage is one of the essential mechanisms of CCl 4 hepatotoxicity, which triggers apoptosis via the mitochondria-initiated pathway.

目的探讨博来霉素(bleomycin,BLM)致大鼠肺纤维化机制. 方法Ⅰ体内试验:雄性SD大鼠,体重220～250 g,60只,随机分成对照组和BLM组(每组50只),用一次性气管内滴注BLM(5 mg/kg,2 mL/kg)的方法复制大鼠肺纤维化模型,对照组滴注生理盐水.

Tetrandrine, a bisbenylisoquinoline alkaloid isolated from the dried root of Stephenia tetrandra (S Moore), possesses a remarkable pharmacological profile. However, the mechanisms of tetrandrine hepatotoxicity remain to be elucidated. In this study, we first proved apoptosis and mitochondrial dysfunction induced by tetrandrine in Sprague–Dawley rat liver in vivo. By further assuming apoptosis as an important mechanism in tetrandrine-induced hepatotoxicity, we focused on mitochondria-initiated apoptosis in primary hepatocytes isolated from Sprague–Dawley male rats. Tetrandrine treatment led to significant release of cytochrome c and downregulation of Bcl-XL accompanied by caspase 3 activation, and ultimately, DNA fragmentation. Caspase 3 activation was markedly inhibited by cyclosporin A (CsA) and Ac-DEVD-CHO. Furthermore, Endo G, a caspase-independent apoptotic protein, was detected for its expression and DNase activity. CsA blocked the release both of Endo G and cytochrome c significantly. Additionally, the generation of reactive oxygen species (ROS) increased in a time-dependent manner corresponding with a fall in intracellular GSH content after 10μM tetrandrine treatment in 4h. Tetrandrine also induced mitochondrial dysfunction indicated by transition of mitochondrial transmembrane potential and decrease of intracellular ATP level. The findings indicated that the caspase-dependent mitochondrial apoptosis pathway was primarily involved in tetrandrine-induced apoptosis in rat primary hepatocytes. In addition, a caspase-independent pathway indicated by Endo G also contributed to apoptosis caused by tetrandrine. Meanwhile, ROS was proved an important inducer in this apoptosis process.

The current therapeutic approaches for pulmonary fibrosis, which is characterized by fibroblast proliferation and extracellular matrix remodeling, are unsatisfactory. Feitai, consisting of several herbs, is a folk formula for pulmonary tuberculosis therapy in China. To investigate the effects of Feitai on pulmonary fibrosis, Feitai was administered orally to bleomycin (BLM)-treated rats, and the lung toxicity effects were evaluated according to inflammatory cell count, protein concentration, and lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF), malondialdehyde level and hydroxyproline content in lung tissue 28 days post-BLM. Serial sections of the lung were stained with hematoxylin and eosin (HE) and Masson trichrome, respectively. The degree of fibrosis was assessed quantitatively using LEICA QWin image analyzer. Results showed that Feitai inhibited BLM-induced lung fibrotic lesions in a dose-dependent manner as reflected by decreased the lung hydroxyproline content and lung fibrosis fraction 28 days after BLM instillation. Treatment with Feitai also significantly ameliorated the BLM-induced lung toxicity effects detected in BALF and lung tissue. The effects in vitro on WI-38 human lung fibroblast cell line showed that Feitai significantly reduced the cell proliferation and transforming growth factor (TGF)–β stimulated type I collagen synthesis. These results strongly demonstrate that Feitai may be useful in the treatment of pulmonary fibrosis.

Pulmonary fibrosis is a common consequence of numerous pulmonary diseases. The current therapeutic approaches for this condition are unsatisfactory. Feitai, a composite formula consisting of several herbs, is used in China as a folk remedy for treating patients with pulmonary tuberculosis. In this study, we extensively investigate the effects and mechanisms of Feitai on bleomycin (BLM)-induced pulmonary fibrosis in rats. One hundred and twenty male Sprague-Dawley rats were randomly divided into four groups, referred to as the saline-water, saline-Feitai, BLM-water, and BLM-Feitai groups. Following a single instillation of BLM (5 mg/kg) or saline, rats were orally administered Feitai at a dose of 3 g/kg body weight or sterilized distilled water once daily. Rats were killed at 7, 14, or 28 d post-BLM. Inflammatory cell count, protein concentration, and lactate dehydrogenase activity in bronchoalveolar lavage fluid were measured, and myeloperoxidase activity and lipid peroxide content in lung homogenates were analyzed. Treatment with Feitai inhibited lung fibrotic progression induced by BLM, as indicated by the decrease in lung hydroproline content and lung fibrosis score at 28 d post-BLM. This was accompanied by significant amelioration of BLM-induced body weight loss, lung edema, and inflammatory response during the development of lung injury in the acute phase. The results strongly indicate the beneficial effects of Feitai in protecting against BLM-induced pulmonary fibrosis. Furthermore, the inflammatory response and lipid peroxidation were inhibited by Feitai, suggesting that the effect of this formula on BLM-induced lung injury and fibrosis is associated with antiinflammatory and antioxidant properties.

Fatty acids, the products of fatty acid synthesis, are essential components and forms of energy for cancer growth. Compared to normal human tissues, many common human cancers express elevated levels of fatty acid synthase (FAS), the important enzyme responsible for the synthesis of fatty acid, suggesting FAS can be a specific target for cancer therapy.