HSC凋亡与肝纤维化逆转的研究进展

肝星状细胞(HSC)在肝纤维化形成中起核心作用,其凋亡是肝纤维化逆转的主要机制之一.深入研究HSC凋亡的调控机理及HSC凋亡在肝纤维化逆转中的作用,对肝纤维化的防治具有重要意义.     

肝纤维化的治疗

1.抗肝纤维化治疗某些新的认识:(1)肝星状细胞(HSC) 的活化过程,细胞因子、多肽、细胞外基质(ECM)等均能致HSC的活化。有报道丙型肝炎病毒(HCV)的核心蛋白与HBxAg也有直接激活HSC的作用。Canbay等指出肝细胞的凋亡能诱导HSC的活化,抑制肝细胞凋亡的一个小分子半胱氨酸-天门冬氨酸蛋白酶抑制剂近年已开始临床试用;还可以通过RNA干扰技术阻止肝细胞凋亡而达抗肝纤维化治疗目的。凋     

抗纤软肝颗粒对肝星状细胞凋亡的影响

探讨抗纤软肝颗粒对肝星状细胞(HSC)凋亡的影响.方法:传代培养的大鼠肝星状细胞系HSC-T6与中药复方抗纤软肝颗粒(终浓度为5mg/ml、2.5mg/ml、1.25mg/ml)及药物血清(5%、10%、20%)共同培养48小时后,应用TUNEL法及流式细胞仪测定细胞凋亡、免疫组化检测Bcl-2/Bax.结果:TUNEL法及流式细胞仪测定结果显示抗纤软肝颗粒药物及含药血清均可诱导HSC凋亡(P＜0.05);并能下调凋亡抑制分子Bcl-2,上调促凋亡分子Bax(P＜0.01).结论:抗纤软肝颗粒可下调Bcl-2/Bax比率,以增加细胞对凋亡的敏感性,从而促进HSC凋亡.     

生存素基因与肝纤维化

在急性和慢性肝损伤中,肝星状细胞(HSC)活化并转化为肌成纤维细胞样细胞是导致肝纤维化的关键.生存素(survivin)基因是近年发现的凋亡抑制蛋白家族成员之一,有研究报道survivin基因在活化的HSC中高表达,而抑制survivin基因可促进HSC凋亡,有望逆转肝纤维化.此文就survivin基因功能、作用机制及...     

肝星状细胞凋亡与肝纤维化逆转

肝星状细胞(HSC)活化是肝纤维化形成的关键因素,但随着活化其凋亡敏感性增强,Fas／Fas-L、p75／NGF、PBR／PBR-L等介导HSC凋亡,金属蛋白酶组织抑制因子、细胞因子和药物等多种因素参与调控HSC凋亡,应用高选择性凋亡因素诱导活化HSC调亡将是治疗和逆转肝纤维化的理想途径。     

β-榄香烯对肝星状细胞凋亡相关蛋白Bcl-2家族的影响

[目的]研究β-榄香烯对肝星状细胞(HSC)凋亡及凋亡相关蛋白的影响。[方法]传代培养的大鼠HSC系HSC-T6与不同剂量β-榄香烯(终浓度为10、5、2.5 mg/L)共同培养48 h后,应用Annexin-V-碘化丙锭染色检测β-榄香烯对HSC凋亡的影响,免疫组化检测凋亡相关蛋白BcL-2/Bax。[结果]β-榄香烯可使HSC凋亡率明显增多,同时可使凋亡抑制分子Bcl-2表达下调,促凋亡分子Bax表达增强(P<0.01)。[结论]β-榄香烯可通过下调Bcl-2/Bax比率,促进HSC凋亡。     

剔毒护肝方药物血清对肝星状细胞凋亡相关蛋白Bcl-2、Bax的影响

目的:研究剔毒护肝方药物血清对肝星状细胞凋亡相关蛋白Bcl-2、Bax的影响.方法:传代培养大鼠肝星状细胞(HSC)系HSC-T6与不同剂量剔毒护肝方(大、中、小剂量组)共同培养48小时,应用Annexin-V-碘化丙锭染色检测剔毒护肝方对大鼠HSC凋亡的影响;免疫组化检测凋亡相关蛋白Bcl-2、Bax水平.结果:剔毒护肝方能使大鼠HSC凋亡率明显增多,同时可使凋亡抑制分子Bcl-2表达下调,促凋亡分子Bax表达增强(P＜0.01).结论:剔毒护肝方可下调Bcl-2/Bax比率,促进HSC凋亡.     

莪术油注射液对肝星状细胞凋亡的影响

在各种治疗肝纤维化的方法中,以肝星状细胞(HSC)为靶点成为目前的研究热点[1-2].国艳等[3]研究发现,莪术油注射液对体外培养的HSC有明显促凋亡作用,但其凋亡机制尚不清楚.我们进一步检测和证实了莪术油注射液对HSC的促凋亡作用;并同时检测促凋亡基因Fas、抑凋亡基因bcl-2与凋亡蛋白酶caspase-3,试图揭示莪术油注射液促进HSC凋亡作用的可能机制.     

α-干扰素对活化的肝星状细胞早期凋亡的影响

目的研究IFN-α对活化的大鼠肝星状细胞(HSC)凋亡的影响,进一步探讨IFN-α抗肝纤维化的机制.方法将体外培养大鼠HSC分别给予不同浓度的IFN-α作用24 h后,采用四甲基偶氮唑蓝实验(MTT)测定活细胞数及应用流式细胞仪(flow cytometry)AnnexinV和PI双染方法将早期凋亡与中晚期凋亡和死细胞区分开,从而测定HSC的早期凋亡情况.结果MTT实验观察到IFN-α作用于大鼠活化的HSC后,作用组活细胞数目减少,1×107及1×108U/L两个作用浓度组与对照组的A值比较有显著性差异(t=2.82,5.44,均P＜0.05).流式细胞仪结果示HSC的早期凋亡率随干扰素浓度的增加而提高,1×107及1×108 U/L两个作用浓度组与对照组比较早期凋亡率有显著性差异(t=4.31,5.07,均P＜0.05).结论诱导肝星状细胞早期凋亡可能是IFN-α抗肝纤维化的机制之一.     

α-干扰素对活化的肝星状细胞早期凋亡的影响

目的:研究IFN-α对活化的大鼠肝星状细胞(HSC)凋亡的影响,进一步探讨IFN-α抗肝纤维化的机制.方法:将体外培养大鼠HSC分别给予不同浓度的IFN-α作用24 h后,采用四甲基偶氮唑蓝实验(MTT)测定活细胞数及应用流式细胞仪(flow cytometry)AnnexinV和PI双染方法将早期凋亡与中晚期凋亡和死细胞区分开,从而测定HSC的早期凋亡情况.结果:MTT实验观察到IFN-α作用于大鼠活化的HSC后,作用组活细胞数目减少,1×10~7及1×10~8U/L两个作用浓度组与对照组的A值比较有显著性差异(t=2.82,5.44,均P<0.05).流式细胞仪结果示HSC的早期凋亡率随干扰素浓度的增加而提高,1×10~7及1×10~8U/L两个作用浓度组与对照组比较早期凋亡率有显著性差异(t=4.31,5.07,均P<0.05).结论:诱导肝星状细胞早期凋亡可能是IFN-α抗肝纤维化的机制之一.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

N-acetyl-L-cysteine combined with mesalamine in the treatment of ulcerative colitis： Randomized,placebo-controlled pilot study

AIM： To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine （NAC） co-administration with mesalamine in ulcerative colitis （UC） patients.
METHODS： Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine （2.4 g/d） plus N-acetyl-L-cysteine （0.8 g/d） （group A） or mesalamine plus placebo （group B）. Patients were monitored using the Modified Truelove-Witts Severity Index （MTWSI）. The primary endpoint was clinical remission （MTWSI ≤ 2） at 4 wk. Secondary endpoints were clinical response （defined as a reduction from baseline in the MTWSI of ≥ 2 points） and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment. RESULTS： Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine （group A） and mesalamine plus placebo （group B） respectively （OR = 1.71; 95% CI： 0.46 to 6.36; P = 0.19; NNT = 7.7）. Analysis of variance （ANOVA） of data indicated a significant reduction of MTWSI in group A （P = 0.046） with respect to basal condition without significant changes in the group B （P = 0.735） during treatment. Clinical responses were 66% （group A） vs 44% （group B） after 4 wk of treatment （OR = 2.5; 95% CI： 0.64 to 9.65; P = 0.11; NNT = 4.5）. Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups.
CONCLUSION： In group A （oral NAC combined with mesalamine） contrarily to group B （mesalamine alone）, the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.     

Delorme's transrectal excision for internal rectal prolapse

Surgical therapy of functional outlet obstruction in patients with internal rectal intussusception may include abdominal, perineal, or transrectal procedures. Because abdominal procedures often result in significant physiologic impact but unrelieved constipation, the authors have elected Delorme's transrectal excision for management of these patients. Since a short-term placebo effect attends many therapies, this report describes results of transrectal excision only after a threeyear postoperative period. Delorme's transrectal excision of internal intussusception accomplished sustained symptomatic relief in over 70 percent of otherwise refractory constipated patients. The association of internal intussusception with other abnormalities underscores the importance of defining both anatomic and functional components when selecting patients whose constipation may require surgical therapy. Critical technical elements, surgical pitfalls, and potential complications of the procedure are discussed.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Toronto, Canada, June 11 to 16, 1989.     

The oral glucose tolerance test: A comparison of the time points on the basis of limit values,normal dispersion,and reproducibility

Summary Time points in the glucose tolerance test (GTT) are compared on the basis of limit values, dispersion within a reference population, and reproducibility. We suggest using the distance between a limit value and the median reference value as a measure of the magnitude of abnormality. The distance between 140 mg/100 ml and the median fasting plasma glucose value is chosen as a standard distance and limits for other points in the GTT are calculated to equal this standard distance of abnormality. We suggest that the probability of correctly interpreting an inividual result is directly related to the reproducibility of the test and inversely related to the percentage of the total range of values which is dispersed among the normal population. The ratio of reproducibility to percentage normal dispersion is proposed as an index of the probability of correctly interpreting an individual result. According to this index, the probability of correct interpretation varies in order: fasting plasma glucose concentration>3-h>2-h>0.5-h>1-h plasma glucose concentration.