Bicyclol: a novel antihepatitis drug with hepatic heat shock protein 27/70-inducing activity and cytoprotective effects in mice

Heat shock proteins (HSPs) are the best-known endogenous factors that protect against cell injury under various pathological conditions and that can be induced by various physical, chemical, and biological stressors. New research seeks to discover a compound that is clinically safe and can induce the accumulation of HSPs in patients. This paper reports that the oral administration of three doses of bicyclol, a novel antihepatitis drug, induced hepatic HSP27 and HSP70 expression in a time- and dose-dependent manner, and that bicyclol treatment stimulated heat shock factor 1 (HSF1) activation in mice. The inducing effects of bicyclol on HSP27, HSP70 and HSF1 were all blocked by quercetin, an inhibitor of HSP biosynthesis. The cytoprotective effect of HSP27/70 induced by bicyclol against hepatotoxicity of acetaminophen (AP) was assessed in mice. The prior administration of bicyclol markedly suppressed AP-induced liver injury as indicated by the reduction in the elevation of serum alanine aminotransferase and aspartate aminotransferase, in liver necrosis, in the release of cytochrome c and apoptosis-inducing factor from mitochondria, as well as in hepatic deoxyribonucleic acid fragmentation in mice. However, all the above actions of bicyclol against AP-induced mouse liver injuries were significantly attenuated by quercetin. This is the first report to show that bicyclol induces hepatic HSP27/70 expression via activation of HSF1 and that the cytoprotective action of bicyclol against liver injury is mediated by its induction of HSP27/70. These results provide new evidence for elucidating the mechanism of the hepatoprotective action of bicyclol in animals and patients.     

Comparative cytotoxicity of alachlor, acetochlor, and metolachlor herbicides in isolated rat and cryopreserved human hepatocytes

Noncancerous adverse effects observed at the lowest dose for chloroacetanilide herbicides alachlor [2-chloro-2',6'-diethyl-N-(methoxymethyl)-acetanilide] and acetochlor [2-chloro-2'-methyl-6'-ethyl-N-(ethoxymethyl)acetanilide], but not metolachlor [2-chloro-2'-ethyl-6'-methyl-N-(1-methyl-2-methoxymethyl)acetanilide], are hepatotoxicity in rats and dogs. Liver microsomal N-dealkylation, a step in the putative activating pathway, of acetochlor exceeds that of alachlor and is negligible for metolachlor. In the present investigation, cytotoxicity of the three chloroacetanilides was ranked using isolated rat and cryopreserved human hepatocytes to correlate this endpoint with CYP3A-dependent metabolism. Chloroacetanilide cytotoxicity in rat hepatocyte suspensions was time dependent (e.g., LC(50 - alachlor/2 h) vs. LC(50 - alachlor/4 h) = 765 vs. 325 muM). Alachlor and acetochlor were more potent than metolachlor after 2 and 4 h, times when N-dealkylated alachlor product 2-chloro-N-(2,6-diethylphenyl)acetamide (CDEPA) formation was readily detectable. Alachlor and acetochlor potencies with cryopreserved human hepatocytes at 2 h were comparable to freshly isolated rat hepatocytes, and alachlor metabolism to CDEPA was likewise detectable. Unlike rat hepatocytes, metolachlor potency was equivalent to acetochlor and alachlor in human hepatocytes. Furthermore, chloroacetanilide cytotoxicity from two sources of human hepatocytes varied inversely with CYP3A4 activity. Collectively, while cytotoxicity in rat hepatocytes was consistent with chloroacetanilide activation by CYP3A, an activating role for CYP3A4 was not supported with human hepatocytes.     

Is the hepatic metabolism of glucose and linoleic acid influenced by species in overfed ducks?

There are genetic differences in the hepatic glucose and linoleic acid metabolisms between Muscovy and Pekin ducks ad libitum-fed. To understand the effect of overfeeding on the hepatic metabolisms in these two species of ducks, we compared the different pathways of glucose and linoleic acid reaching the liver of Muscovy (Cairina moschata) (n = 6) and Pekin (Anas platyrhynchos) (n = 6) ducks overfed for 1 week and sacrificed 2–4 h after their last meal by using the ex vivo method of liver slices incubated for 16 h with [U-¹⁴C]-glucose, [1-¹⁴C]-linoleic acid and [³⁵S]-methionine added to the survival medium. The glucose was the main precursor of triacylglycerol synthesis in the liver of these two species and its hepatic metabolism was similar between species. The hepatic uptake of linoleic acid was 1.7-fold higher (P = 0.020) in the Muscovy duck than in the Pekin duck leading to a 1.9-fold higher (P = 0.017) esterification of this fatty acid in the liver of the Muscovy duck than in that of the Pekin duck. Finally, both species after 1 week of overfeeding exhibited the same capacity to secrete VLDL remaining insufficient to avoid hepatic steatosis.     

Liver Ischemia and Ischemia–Reperfusion Induces and Trafficks the Multi-specific Metal Transporter Atp7b to Bile Duct Canaliculi: Possible Preferential Transport of Iron into Bile

Both Atp7b (Wilson disease gene) and Atp7a (Menkes disease gene) have been reported to be trafficked by copper. Atp7b is trafficked to the bile duct canaliculi and Atp7a to the plasma membrane. Whether or not liver ischemia or ischemia–reperfusion modulates Atp7b expression and trafficking has not been reported. In this study, we report for the first time that the multi-specific metal transporter Atp7b is significantly induced and trafficked by both liver ischemia alone and liver ischemia–reperfusion, as judged by immunohistochemistry and Western blot analyses. Although hepatocytes also stained for Atp7b, localized intense staining of Atp7b was found on bile duct canaliculi. Inductive coupled plasma-mass spectrometry analysis of bile copper, iron, zinc, and manganese found a corresponding significant increase in biliary iron. In our attempt to determine if the increased biliary iron transport observed may be a result of altered bile flow, lysosomal trafficking, or glutathione biliary transport, we measured bile flow, bile acid phosphatase activity, and glutathione content. No significant difference was found in bile flow, bile acid phosphatase activity, and glutathione, between control livers and livers subjected to ischemia–reperfusion. Thus, we conclude that liver ischemia and ischemia–reperfusion induction and trafficking Atp7b to the bile duct canaliculi may contribute to preferential iron transport into bile.     

肝移植术后营养治疗

近30多年来,肝移植技术已逐步成熟,并迅速发展成为治疗终末期肝病的首选方法。随着肝移植例数的增加,手术经验的积累,手术技巧的提高,与手术相关的并发症逐渐减少。而许多围手术期因素成为影响肝移植成败的关键。适宜的肝移植围手术期营养治疗,可以提高手术成功率,降低术后并发症,促进受体和移植肝功能的恢复,从而改善预后,提高受体与移植肝的近远期存活率。     

Changes in the proteome of Huh7 cells induced by transient expression of hepatitis D virus RNA and antigens

Hepatitis delta virus (HDV) infection of human hepatocytes infected with the hepatitis B virus (HBV) is associated with increased liver damage and risk of fulminant disease. Although considerable progress has been made towards the elucidation of the mechanisms of HDV replication and pathogenesis, little is still known about the host factors involved in the different steps of the replication cycle. Here, we made use of a proteomic approach to analyse the global alterations in protein expression that arise in human hepatocytes separately transfected with each of the HDV components. Huh7 cells were transiently transfected with plasmids that code for the small delta antigen (S-HDAg), large delta antigen (L-HDAg), genomic RNA (gRNA), and antigenomic RNA (agRNA), respectively. Total protein extracts were separated by 2-DE and differentially expressed spots were identified by MALDI-TOF followed by database searching. We identified 32 proteins known to be involved in different pathways namely nucleic acid metabolism, protein metabolism, transport, signal transduction, apoptosis, and cell growth. Moreover, the down regulation of hnRNP D, HSP105, and triosephosphate isomerase was further confirmed by Real time PCR.     

Plasma transport and tissue distribution of β-carotene, vitamin A and retinol-binding protein in domestic cats

The objective of this study was to determine retinol, retinyl esters and retinol-binding protein (RBP) as well as carotenoids in plasma, urine, liver and kidneys of randomly selected domestic cats. Retinol (240±64 ng/ml, mean±S.D.) represented one-third of total retinyl esters (736±460 ng/ml) in plasma. Retinyl esters were stearate, palmitate and oleate representing 61±6, 36±13 and 5±3% of total retinyl esters, respectively. In half of the cats, retinyl esters (22±21 ng/ml) were found in the urine. Vitamin A in the livers (4317±1956 μg/g) was significantly higher than in the kidney cortex and medulla (14.16±8.92 and 7.59±4.52 μg/g, respectively, both P<0.001). RBP was detected in the plasma but not in the urine. Immunoreactive RBP was observed in hepatocytes and in the cells of the proximal tubules. β-Carotene was present in plasma but never in tissues. The results show that similar to canines differences in vitamin A metabolism in cats are related to the occurrence of retinyl esters in plasma. They differ, however, with regard to the tissue distribution of β-carotene and the excretion of vitamin A in the urine.     

Quantitative Proteomics and Targeted Fatty Acids Analysis Reveal the Damage of Triptolide in Liver and Kidney

Triptolide (TP), the major active component in Tripterygium wilfordii Hook. f., is widely used for the treatment of rheumatoid arthritis and autoimmune diseases. However, organ toxicity, especially hepatotoxicity and nephrotoxicity, limits its clinical application. To fully understand the mechanism underlying TP toxicity, iTRAQ‐based 2D‐LC‐MS/MS proteomics is used to detect differentially expressed proteins in the livers and kidneys of mice administered the LD50 dose of TP. Functional annotation revealed that multiple pathways are involved in TP toxicity, including acute‐phase response signaling, the antigen presentation pathway, FXR/RXR activation, LPS/IL‐1‐mediated inhibition of RXR function, and EIF2 signaling. Members of the cytochrome P450 protein family that are involved in fatty acid (FA) metabolism, such as CYP2E1, show significant differences in expression among groups. Additionally, the proteomics data suggested that FAs are involved in TP‐induced toxicity. FA analysis is conducted using HPLC‐MRM to characterize the differences among various groups exposed to TP for different times. It has been found that 20 FAs in the liver show significant differences in abundance among groups, whereas in the kidneys, six FAs show significant differences in abundance. By integrating the proteomic and targeted FA analyses, it has been found that differently expressed proteins and FAs both participate in pathways including cellular lipolytic activity, peroxisomal fatty acid beta‐oxidation, and so on. Our data contribute to understanding the mechanisms underlying TP‐induced organ toxicity. The results may help to improve the clinical efficacy and safety of TP in the future.     

草鱼不同组织胆汁酸组成分析

正胆汁酸是由胆固醇通过一系列酶促反应在肝细胞中合成的,根据侧链羟基数目的多少胆汁酸分为初级胆汁酸和次级胆汁酸。初级胆汁酸随食物到达肠道,在肠道微生物的作用下脱羟基形成次级胆汁酸~([1])。初级胆汁酸和次级胆汁酸都可与牛磺酸或者甘氨酸结合形成结合型胆汁酸。肝脏中合成的以及经由肠肝循环回到肝脏的胆汁酸都被储存在胆囊中。胆汁酸的主要生理功能是帮助脂溶性营养物质的消化吸收,高脂肪的摄入刺激胆汁酸     

Protective effect of some plant oils on diazinon induced hepatorenal toxicity in male rats

Environmental pollution and exposure to environmental pollutants are still some of the major global health issues. Pesticides have been linked to a wide range of health hazards. The toxicity of pesticides depends on several factors such as its chemical properties, doses, exposure period, exposure methods, gender, genetics, age, nutritional status and physiological case of exposed individuals. Medicinal plants, natural products and nutrition continue to play a central role in the healthcare system of large proportions of the world’s population. Alternative medicine plays an important role in health services around the world. The aim of this study was to investigate the effect of olive, sesame and black seed oils on hepatorenal toxicity induced by diazinon (DZN) in male rats. The experimental animals were divided into nine groups. The first group served as control. The second group was exposed to DZN. The third group was treated with olive oil and DZN. Rats of the fourth group were subjected to sesame oil and DZN. Rats of the fifth group were exposed to black seed oil and DZN. The sixth, seventh and eighth groups were supplemented with olive, sesame and black seed oils respectively. Rats of the ninth group were treated with corn oil. Levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, total bilirubin, creatinine, blood urea nitrogen and malondialdehyde were significantly increased in rats exposed to DZN. Moreover, levels of serum glutathione and superoxide dismutase were significantly decreased. Several histopathological changes were observed in the structures of liver and kidney due to DZN exposure. This study showed that these oils attenuated the physiological disturbances and histopathological alterations induced by DZN intoxication. Moreover, the antioxidant properties of these oils support the bioactive roles of its protective effects on DZN toxicity. This study therefore suggests that these oils could be used as preventive factors against the toxicity of DZN due to its antioxidant properties.