Objective To systematically evaluate the effectiveness of N-acetylcysteine (NAC) combined with low-dose glucocorticoid for patients with idiopathic pulmonary fibrosis (IPF). Methods Such databases as The Cochrane Library (Issue 12, 2012), EMbase (January 1974 to July 2012), PubMed (January 1966 to July 2012), CHEST (January 1995 to July 2012), CNKI (January 1994 to July 2012), CBM (January 1978 to July 2012), VIP (January 1989 to July 2012) and WanFang Data (January 1995 to July 2012) were searched to collect the randomized controlled trials (RCTs) about NAC combined with low-dose glucocorticoid versus glucocorticoid alone for IPF patients. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted the data, and assessed the quality, and then the meta-analysis was performed using RevMan 5.1 software. Results A total of seven RCTs including 264 IPF patients were included. The results of meta-analysis demonstrated that, compared with the glucocorticoid used alone, a) NAC combined with low-dose glucocorticoid could significantly improve PaO2 (SMD=0.82 mmHg, 95%CI 0.30 to 1.35, P=0.002) and DLco (SMD=0.59 mmHg, 95%CI 0.16 to 1.03, P=0.008) with a significant difference. b) NAC combined with low-dose glucocorticoid could significantly improve all clinical symptoms (RR=1.56, 95%CI 1.26 to 1.92, Plt;0.000 1). Conclusion NAC combined with low-dose glucocorticoid for IPF patients can significantly improve PaO2, DLco, and the clinical symptoms such as cough, difficulty breathing after activities, cyanosis, and Velcro rales. Due to the quantity and quality limitation of included studies, this conclusion still needs to be further proved by more high quality and double blind RCTs.
目的：探讨N-乙酰半胱氨酸对烫伤大鼠炎症反应的影响。方法：48只Wistar大鼠随机分为实验组和对照组，制作烫伤休克模型，伤后1小时腹腔注射生理盐水40ml/kg抗休克，实验组于抗休克盐水中加入N-乙酰半胱氨酸160mg/kg，其后足量饮水。分别于烫伤前、烫伤后8小时、16小时及24小时，处死每组各6只大鼠并立即心脏取血，采用ELISA法检测大鼠血清中TNF-a含量，于创周近头侧 0.5cm处取皮肤全层组织，在显微镜下进行中性粒细胞计数。 结果：两组大鼠血清TNF-a含量伤后显著升高，8小时达到高峰，其后逐渐下降，两组各时点比较有显著差异（P＜0.05）；创周组织中性粒细胞计数于伤后随时间延长逐渐增多，两组比较有显著性差异（P＜0.05）。 结论：N-乙酰半胱氨酸有助于降低烫伤大鼠血浆中TNF-a含量及创周组织中的中性粒细胞计数量，减轻烫伤大鼠的全身及局部炎症反应。
Objective To investigate the effect of N-acetylcysteine (NAC) on the apoptosis during myocardial ischemia reperfusion injury in rats’ heart transplantation, and to explore the possible role of NAC in myocardial apoptosis. Methods Sixty healthy male Lewis rats (weighing, 200-220 g) were randomly divided into 3 groups, 20 rats each group (10 donors and 10 recipients). In control group, 1 mL normal saline was infused via inferior vena cava at 30 minutes before donor harvesting; in donor preconditioning group, NAC (300 mg/kg) was infused via inferior vena cava at 30 minutes before donor harvesting, but no treatment in recipients; and in recipient preconditioning group, NAC (300 mg/kg) was infused via inferior vena cava at 30 minutes before recipient transplantation, but no treatment in donors. Heart transplantation was established in each group. Blood was drawn at 6 and 24 hours after reperfusion for analysis of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) as markers of graft injury; myocardial tissue was harvested to determine the superoxide dismutase (SOD) and lipid hydroperoxide (LPO) activity at 24 hours after reperfusion and to observe the histology and ultrastructural changes. Graft active Caspase-3 protein expression was measured by immunohistochemistry staining, and apoptosis index (AI) was calculated by TUNEL. Results The heart transplantation operation was successfully completed in all groups, and the rats survived to the end of the experiment. The serum levels of AST, ALT, and LDH in donor and recipient preconditioning groups were significantly lower than those in control group at 6 hours after reperfusion (P lt; 0.05); the levels of AST and ALT in donor preconditioning group and the levels of AST and LDH in recipient preconditioning group were significantly lower than those in control group at 24 hours (P lt; 0.05); and no significant difference was found between donor and recipient perconditioning groups (P gt; 0.05). The levels of AST, ALT, and LDH at 24 hours were significantly lower than those at 6 hours in each group (P lt; 0.05) except the level of ALT in recipient preconditioning group (P gt; 0.05). SOD activity and SOD/LPO in donor and recipient preconditioning groups were significantly higher than those in control group (P lt; 0.05), but no significant difference between donor and recipient preconditioning groups (P gt; 0.05); there was no significant difference in LPO activity among 3 groups (P gt; 0.05). Histological staining and transmission electron microscope showed that myocardial injury in recipient preconditioning group was obviously lighter than that in donor preconditioning group and control group. Active Caspase-3 in recipient pretreatment group was significantly higher than that in donor preconditioning group and control group (P lt; 0.05). AI of donor and recipient preconditioning groups was significantly lower than that of control group (P lt; 0.05), but no significant difference was found between donor and recipient preconditioning groups (P gt; 0.05). Conclusion NAC can relieve ischemia reperfusion injury in rats’ heart transplantation by improving myocardial SOD content, and reducing active Caspase-3 activity and AI, which has a protective effect on myocardial cell of donor heart.
Objective To estimate the effects of N-acetylcystein (NAC) combined with conventional treatment on the patients with stable COPD. Methods Literatures published between January 1995 and September 2010 were searched in the databases including PubMed, CHEST, CNKI, CBM, VIP and WANGFANG for collecting the randomized control trials (RCTs) of NAC combined with the conventional treatment versus the conventional treatment on patients with stable COPD. The studies were screened according to the inclusive and exclusive criteria, the data were extracted, the quality was assessed and the meta-analysis was conducted with RevMan 5.0 software. Results A total of seven RCTs including 404 patients with stable COPD were enrolled. The meta-analysis demonstrated that, a) the short-term usage of NAC could improve PaO2 (SMD=0.05 mmHg, 95%CI –0.23 to 0.32) and PaCO2 (SMD= –0.29 mmHg, 95%CI –0.76 to 0.17) without significant differences compared with the control group; and b) the NAC could significantly improve FEV1 (SMD=1.11L, 95%CI 0.69 to 1.50) and clinical symptoms (RR=17.32, 95%CI 7.11 to 42.18), and reduce the frequency of acute exacerbation (RR=0.20, 95%CI 0.07 to 0.54) with significant differences. Conclusion The NAC used in a short-term can significantly improve arterial blood gas (ABG) and pulmonary function, and it can improve clinical symptoms and reduce the frequency of acute exacerbation. But for the possibility of moderate bias due to lower quality of the included studies and unclear implementation of RCTs, this conclusion should be cautiously applied in clinic with patients’ conditions in considered and it has to be verified with more large-scale and high-quality RCTs.
Objective To investigate the effects of N-acetylcysteine （NAC） on the intestinal barrier in rats with severe acute pancreatitis （SAP） and its possible mechanism. Methods Eighty Wistar rats were randomly （random number method） divided into normal control group （CON group， n=8）， sham operation group （SO group， n=24）， SAP group （n=24）， and NAC group （n=24）， then the rats of latter 3 groups were sub-divided into 6， 12， and 24 hours group， each time point group enrolled 8 rats， respectively. Rats of CON group didn’t receive any treatment. SAP rat models were established by injecting 5.0% sodium taurocholate into the biliary-pancreatic duct for SAP group and NAC group， while rats of SO group were injected normal saline instead of sodium taurocholate. The rats of NAC group were given an intraperitoneal injection of NAC at 1 hour before operation， and the rats of SO group and SAP group were given an intraperitoneal injection of normal saline instead at the same time. Rats of CON group were sacrificed to get ileum （about 5cm） and blood from right ventricular （5mL） for further test， and rats of the other 3 groups were sacrificed at 6， 12， and 24hours after operation. Then the levels of amylase （AMY）， C-reactive protein （CRP）， endotoxin， D-lactic acid， and diamine oxidase （DAO） in plasma， the levels of superoxide dismutase （T-SOD）， myeloperoxidase （MPO）， and malondialdehyde （MDA） in ileum tissues were tested. Apoptosis of mucosal cells in ileum tissues was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL）. Pathological changes in ileum tissues were observed and scored. Expression levels of bax and bcl-2mRNA in ileum tissues were determined by real-timefluorescence quantitative PCR （real-time PCR）， and related proteins were tested by Western blot method， respectively. Results Compared with SAP group at the same time point， the levels of CRP in NAC group were lower at all the 3 time points （P＜0.05） and AMY were lower at 12 and 24 hours （P＜0.05）， levels of DAO， endotoxin， and D-lactic acid were lower at 12 and 24 hours （P＜0.05）， but level of DAO was higher than SAP group at 6 hours （P＜0.05）. Compared with SAP group at the same time point， the levels of MPO and MDA in ileum tissues were lower in NAC group at all the 3 time points （P＜0.05）， but levels of T-SOD increased significantly at 12 and 24 hours （P＜0.05）. Compared with SAP group at the same time point， the apoptosis indexes were lower in NAC group at all the 3 time points （P＜0.01）， and pathologic scores of ileum tissues were lower at 12 and 24 hours （P＜0.05）. The pathological changes under a light microscope were observed better in NAC group than that of SAP group at each time point. Moreover， compared with SAP group at the same time point， the expression levels of bax mRNA and protein were lower in NAC group at all the 3 time points （P＜0.05）， while higher in bcl-2 mRNA and protein （P＜0.05）. Conclusions NAC can protect the function of small intestinal barrier， and can alleviate SAP-induced injury of the intestinal mucosa. In addition to antioxidant effects， the underlying mechanisms also may include the anti-apoptotic effects.
ObjectiveTo systematically review the efficacy and safety of N-acetylcysteine (NAC) for patients with idiopathic pulmonary fibrosis (IPF). MethodsWe electronically searched PubMed, EMbase, The Cochrane Library (Issue 2, 2014), CNKI, WanFang Data and VIP databases from the date of establishment to February 2014 for all randomized controlled trials (RCTs) on the use of NAC in patients with IPF. Manual search in relevant journals were also performed. The data extraction and quality assessment of included RCTs were conducted by two reviewers independently. Then, meta-analysis was conducted using RevMan 5.1 software. ResultsA total of 13 RCTs involving 713 patients were included. The results of meta-analysis indicated that the NAC group was better than the control group in clinical effectiveness (RR=1.34, 95%CI 1.19 to 1.51, P < 0.000 1). After treatment, the lung function was also improved in the NAC group than in the control group in the following index:PaO2 (MD=6.06, 95%CI 3.79 to 8.32, P < 0.000 01), vital capacity (VC) (%) (MD=4.79, 95%CI 0.35 to 9.24, P=0.03) and diffusing capacity of carbon monoxide (Dlco) (%) (MD=5.74, 95%CI 2.67 to 8.81, P=0.000 2). However, no significant difference was found between groups in total lung capacity (TLC) (%) (MD=5.56, 95%CI-1.73 to 12.86, P=0.14). No serious or frequently-happened adverse effect was reported in the NAC group. ConclusionThe current evidence suggests that NAC in long term use could improve clinical conditions, PaO2 and lung function of IPF patients, with less adverse effects.
ObjectiveTo evaluate the effects of N-acetylcysteine (NAC) on lung tissue of Wistar rats, which were tracheally instilled fine particulate matter (PM2.5).MethodsForty-eight male Wistar rats were randomly divided into six groups: two control groups [they were blank group (C1), fake treatment group (C2) separately], four treatment groups [they were PM2.5 group (P), low-dose NAC group (L), medium-dose NAC group (M), high-dose NAC group (H) separately]. C1 received no treatments at all. C2 was instilled with sterile water (1 ml/kg) tracheally once a week for four times. P was instilled equivoluminal PM2.5 suspension (7.5 mg/kg) tracheally once a week for four times. The NAC groups received gavage (10 ml/kg) of different dosage of NAC (125, 250, 500 mg/kg) for six days. At the seventh day, the NAC groups were instilled PM2.5 suspension (7.5 mg/kg) tracheally. The procedures were repeated for three times in the NAC groups. Twenty-four hours later after four weeks or after the last instilling, all rats were sacrificed. Lung tissue was stained by hematoxylin-eosin (HE) staining, and histopathological changes of lung tissue were observed by optical microscope. The levels of C-reactive protein (CRP) as well as tumor necrosis factor-α (TNF-α) of serum, TNF-α of bronchoalveolar lavage fluid (BALF), TNF-α as well as interleukin-1β (IL-1β) of homogenates of lung tissue were detected by enzyme-linked immunosorbent assay. The activity of lactate dehydrogenase (LDH) as well as the levels of malondialhyde (MDA) of serum and BALF were detected by standard colorimetric method.ResultsHE staining showed that the normal structure of lung were destroyed in the groups dealed with PM2.5 and NAC could alleviate these changes. Higher dosage of NAC seemed to provide more powerful protections. Structure of the lung in C1 as well as C2 were nearly normal. The levels of CRP as well as TNF-α of serum, TNF-α of BALF, TNF-α as well as IL-1β of homogenates of lung tissue in the groups of P, L, M, H were higher than that in the groups of C1, C2 (all P<0.05). The levels of CRP as well as TNF-α of serum, TNF-α of BALF, TNF-α as well as IL-1β of homogenates of lung tissue in the groups of L, M, H which groups received NAC treatments were lower than that in P group. More, the groups seemed to have lower levels of CRP, TNF-α, IL-1β when higher dosage of NAC were given. The activity of LDH as well as the levels of MDA of serum, and BALF in the groups of P, L, M, H were higher than that in the groups of C1, C2 (all P<0.05). The activity of LDH as well as the levels of MDA of serum and BALF in the groups of L, M, H which groups received NAC treatments were lower than that in P group (all P<0.05). ConlusionTo some extent, NAC demonstrate antagonistic effects on oxidative stress and inflammatory injury on rats’ lung brought by PM2.5.