Vitamin E has a dual effect of anti-inflammatory and antioxidant activities in acetic acid-induced ulcerative colitis in rats

BACKGROUND

Increased free radical production, decreased antioxidant capacity and excessive inflammation are well-known features in the pathogenesis of inflammatory bowel disease. Vitamin E is a powerful antioxidant and a scavenger of hydroxyl radicals, and it has been shown to have anti-inflammatory activities in tissues. We investigated the effects of vitamin E on inflammatory activities using an acetic acid (AA)-induced ulcerative colitis model in rats.

METHODS

Wistar rats were divided into 4 groups. Acetic acid was given to 2 groups of animals to induce colitis while the other 2 groups received saline intrarectally. One AA-induced colitis group and 1 control group received vitamin E (30 U/kg/d) intraperitoneally and the pair groups received saline. After 4 days, we evaluated colonic changes biochemically by measuring proinflammatory cytokine levels in tissue homogenates and by histopathologic examination.

RESULTS

Acetic acid caused colonic mucosal injury, whereas vitamin E administration suppressed these changes in the AA-induced colitis group (p < 0.001). Administration of AA resulted in increased levels of tumour necrosis factor-α, interleukin-1β, interleukin-6, myeloperoxidase and malondialdehyde, and decreased levels of glutathione and superoxide dismutase; vitamin E reversed these effects (all p < 0.001).

CONCLUSION

Our study proposes that vitamin E is an effective anti-inflammatory and antioxidant and may be a promising therapeutic option for ulcerative colitis.

Hepatic differentiation of amniotic epithelial cells

Hepatocyte transplantation to treat liver disease is largely limited by the availability of useful cells. Human amniotic epithelial cells (hAECs) from term placenta express surface markers and gene characteristics of embryonic stem cells and have the ability to differentiate into all three germ layers, including tissues of endodermal origin (i.e., liver). Thus, hAECs could provide a source of stem cell-derived hepatocytes for transplantation. We investigated the differentiation of hAECs in vitro and after transplantation into the livers of severe combined immunodeficient (SCID)/beige mice. Moreover, we tested the ability of rat amniotic epithelial cells (rAECs) to replicate and differentiate upon transplantation into a syngenic model of liver repopulation. In vitro results indicate that the presence of extracellular matrix proteins together with a mixture of growth factors, cytokines, and hormones are required for differentiation of hAECs into hepatocyte-like cells. Differentiated hAECs expressed hepatocyte markers at levels comparable to those of fetal hepatocytes. They were able to metabolize ammonia, testosterone, and 17α-hydroxyprogesterone caproate, and expressed inducible fetal cytochromes. After transplantation into the liver of retrorsine (RS)-treated SCID/beige mice, naïve hAECs differentiated into hepatocyte-like cells that expressed mature liver genes such as cytochromes, plasma proteins, transporters, and other hepatic enzymes at levels equal to adult liver tissue. When transplanted in a syngenic animal pretreated with RS, rAECs were able to engraft and generate a progeny of cells with morphology and protein expression typical of mature hepatocytes.

CONCLUSION

Amniotic epithelial cells possess the ability to differentiate into cells with characteristics of functional hepatocytes both in vitro and in vivo, thus representing a useful and noncontroversial source of cells for transplantation.

Melatonin expresses powerful anti-inflammatory and antioxidant activities resulting in complete improvement of acetic-acid-induced colitis in rats

INTRODUCTION

Increased free-radical production, decreased antioxidant capacity, and excessive inflammation are well-known features in the pathogenesis of inflammatory bowel disease. Melatonin is a powerful antioxidant and a scavenger of hydroxyl radicals. Melatonin has also been shown to have anti-inflammatory activities in tissues. Our study objective is to investigate the effects of melatonin on tissue inflammatory activities using an ulcerative colitis (UC) model induced by acetic acid (AA) in rats.

METHODS

Wistar rats (n = 32) were divided into four groups. AA-induced colitis was performed in two of the groups, while the other two groups were injected with saline intrarectally. One of the AA-induced colitis groups and one of the control groups were administered 100 mg/kg/day melatonin intraperitoneally, and the pair groups were given saline. After 4 days, colonic changes were evaluated biochemically by measuring proinflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6], myeloperoxidase (MPO), malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels in tissue homogenates and by histopathological examination.

RESULTS

AA caused colonic mucosal injury, whereas melatonin suppressed these changes in the AA-induced colitis group (P < 0.001). AA administration resulted in increased TNF-α, IL-1β, IL-6, MPO, and MDA levels, and decreased GSH and SOD levels, whereas melatonin administration reversed these effects (all P < 0.001).

CONCLUSIONS

The present study proposes that melatonin has a dual action as an effective anti-inflammatory and an antioxidant, and may be a hopeful therapeutic agent for UC.

Sexual transmission of HCV between spouses

BACKGROUND AND AIMS

The sexual transmission of hepatitis C virus (HCV) is debated. By excluding other risk factors, the role of sexual intercourse in the transmission could be detected more accurately. We screened HCV prevalence and risk factors in the spouses of chronic hepatitis C (CHC) patients and followed the seroconversion rate of anti-HCV negative spouses.

PATIENTS AND METHODS

Six hundred spouses of CHC patients were recruited. The spouses' HCV risk factors were questioned and the spouses were tested for anti-HCV. The 216 spouses who were anti-HCV negative were checked annually for anti-HCV.

RESULTS

Anti-HCV was positive in 12 of 600 (2%) of the spouses. Of the 12 anti-HCV positive spouses, 11 were HCV-RNA positive. Of anti-HCV positive and negative spouse groups, mean age was 52.3 +/- 9.8 and 49.8 +/- 12.4 yr; duration of marriage was 1521 +/- 506.7 and 1532.4 +/- 670.2 wk (p > 0.05); and the number of total sexual intercourse was 434 +/- 295 and 307 +/- 333 (p= 0.055), respectively. In our prospective study, none of the spouses developed anti-HCV seroconversion in mean 35.7 +/- 6.3 months and 257.9 +/- 72.2 sexual intercourse.

CONCLUSIONS

Anti-HCV was found positive in 2% of the spouses. None of the seronegative spouses developed seroconversion in the 3-yr follow-up period. This is the first study that stresses the importance of the total number of sexual intercourse in sexual transmission (p= 0.055). Our results of special monogamous group with very limited risk factors support the role of number of total sexual intercourse in HCV transmission. However, the seroprevalence rate of the spouses was still within the upper limit of our country population.

Role of ursodeoxycholic acid in prevention of methotrexate-induced liver toxicity

AIM

Methotrexate (MTX)-induced hepatotoxicity restricts the clinical use of this immunosuppressive drug. In this study, our aim was to research the role of oxidative stress in the hepatic toxicity of MTX and the protective effect of ursodeoxycholic acid (UDCA) in this setting.

METHODS

Wistar type rats (n = 32) were divided into four groups; group-1 as the MTX + UDCA, group-2 as the MTX, group-3 as the UDCA, group-4 as the saline-receiving groups. The MTX + UDCA and MTX groups of rats received 50 mg/kg of UDCA administered orally; whilst physiological saline was administered orally to the MTX and saline groups and continued for the next 6 days. On the second day of the study, the MTX + UDCA and MTX groups had a single intraperitoneal dose of MTX of 20 mg/kg. The UDCA and saline groups also received similar volumes of physiological saline intraperitoneally. On the sixth day, serum samples were collected and analyzed for ALT, alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) and homogenated liver tissues were examined for reactive oxygen metabolites (ROM); luminol, lucigenin, lipid peroxygenation product malondialdehyde (MDA) and glutathione (GSH) levels.

RESULTS

In the MTX group, serum ALT, ALP, GGT and tissue ROM levels were higher and GSH level was lower. On the histopathological examination, hepatocellular necrosis was clearly more evident in the MTX group than the MTX + UDCA group.

CONCLUSIONS

UDCA treatment protects against MTX-induced liver toxicity. Histopathologically hepatocyte necrosis can be prevented by UDCA treatment, indicating clearly the hepatoprotective effect of this agent on MTX-induced liver injury.

Host conditioning and rejection monitoring in hepatocyte transplantation in humans

BACKGROUND & AIMS

Hepatocyte transplantation partially corrects genetic disorders and has been associated anecdotally with reversal of acute liver failure. Monitoring for graft function and rejection has been difficult, and has contributed to limited graft survival. Here we aimed to use preparative liver-directed radiation therapy, and continuous monitoring for possible rejection in an attempt to overcome these limitations.

METHODS

Preparative hepatic irradiation was examined in non-human primates as a strategy to improve engraftment of donor hepatocytes, and was then applied in human subjects. T cell immune monitoring was also examined in human subjects to assess adequacy of immunosuppression.

RESULTS

Porcine hepatocyte transplants engrafted and expanded to comprise up to 15% of irradiated segments in immunosuppressed monkeys preconditioned with 10Gy liver-directed irradiation. Two patients with urea cycle deficiencies had early graft loss following hepatocyte transplantation; retrospective immune monitoring suggested the need for additional immunosuppression. Preparative radiation, anti-lymphocyte induction, and frequent immune monitoring were instituted for hepatocyte transplantation in a 27year old female with classical phenylketonuria. Post-transplant liver biopsies demonstrated multiple small clusters of transplanted cells, multiple mitoses, and Ki67+ hepatocytes. Mean peripheral blood phenylalanine (PHE) level fell from pre-transplant levels of 1343±48μM (normal 30-119μM) to 854±25μM (treatment goal ≤360μM) after transplant (36% decrease; p<0.0001), despite transplantation of only half the target number of donor hepatocytes. PHE levels remained below 900μM during supervised follow-up, but graft loss occurred after follow-up became inconsistent.

CONCLUSIONS

Radiation preconditioning and serial rejection risk assessment may produce better engraftment and long-term survival of transplanted hepatocytes. Hepatocyte xenografts engraft for a period of months in non-human primates and may provide effective therapy for patients with acute liver failure.

LAY SUMMARY

Hepatocyte transplantation can potentially be used to treat genetic liver disorders but its application in clinical practice has been impeded by inefficient hepatocyte engraftment and the inability to monitor rejection of transplanted liver cells. In this study, we first show in non-human primates that pretreatment of the host liver with radiation improves the engraftment of transplanted liver cells. We then used this knowledge in a series of clinical hepatocyte transplants in patients with genetic liver disorders to show that radiation pretreatment and rejection risk monitoring are safe and, if optimized, could improve engraftment and long-term survival of transplanted hepatocytes in patients.

N-acetylcysteine attenuates alcohol-induced oxidative stress in the rat

AIM

There is increasing evidence that alcohol-induced liver damage may be associated with increased oxidative stress. We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically fed with ethanol.

METHODS

Twenty-four rats divided into three groups were fed with ethanol (6 g/kg/day, Group 1), ethanol and n-acetylcysteine (1 g/kg, Group 2), or isocaloric dextrose (control group, Group 3) for 4 weeks. Then animals were sacrificed under ether anesthesia, intracardiac blood and liver tissues were obtained. Measurements were performed both in serum and in homogenized liver tissues. Malondialdehyde (MDA) level was measured by TBARS method. Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) levels were studied by commercial kits. Kruskal-Wallis test was used for statistical analysis.

RESULTS

ALT and AST in Group 1 (154 U/L and 302 U/L, respectively) were higher than those in Group 2 (94 U/L and 155 U/L) and Group 3 (99 U/L and 168 U/L) (P=0.001 for both). Serum and tissue levels of MDA in Group 1 (1.84 nmol/mL and 96 nmol/100 mg-protein) were higher than Group 2 (0.91 nmol/mL and 64 nmol/100 mg-protein) and Group 3 (0.94 nmol/mL and 49 nmol/100 mg-protein) (P<0.001 for both). On the other hand, serum GSH-Px level in Group 1 (8.21 U/g-Hb) was lower than Group 2 (16 U/g-Hb) and Group 3 (16 U/g-Hb) (P<0.001). Serum and liver tissue levels of SOD in Group 1 (11 U/mL and 26 U/100 mg-protein) were lower than Group 2 (18 U/mL and 60 U/100 mg-protein) and Group 3 (20 U/mL and 60 U/100 mg-protein) (P<0.001 for both).

CONCLUSION

This study demonstrated that ethanol-induced liver damage is associated with oxidative stress, and co-administration of n-acetylcysteine attenuates this damage effectively in rat model.

The dirty aspects of fecal microbiota transplantation: a review of its adverse effects and complications

Fecal microbiota transplantation is becoming a growing therapy for a variety of indications, including recurrent or refractory Clostridium difficile infection (CDI), as well as many other gastrointestinal and extra-intestinal diseases. In fact, fecal microbiota transplantation is now strongly recommended as the treatment of choice for multiple recurrences of CDI, given its strong efficacy and a favorable short-term side effect profile. As the application of this therapy expands, awareness of its adverse events has also developed. The purpose of this review is to bring to light the side effects and complications associated with fecal microbiota transplantation, with an emphasis on findings from recently published studies.

Development and application of purified tissue dissociation enzyme mixtures for human hepatocyte isolation

Human hepatocyte transplantation is gaining acceptance for the treatment of liver diseases. However, the reagents used to isolate hepatocytes from liver tissue are not standardized and show lot-to-lot variability in enzyme activity and endotoxin contamination. For clinical application, highly purified reagents are preferable to crude digest preparations. A purified tissue dissociating enzyme (TDE) preparation (CIzyme(TM) purified enzymes) was developed based on the enzyme compositions found in a superior lot of collagenase previously used by our group for human hepatocyte isolation. The performance of this enzyme preparation was compared to collagenase type XI on 110 liver cases by assessing hepatocyte yield, viability, and seven other functional assays that included plating efficiency, basal and induced CYP450 activities, phase II conjugation activity, and ammonia metabolism. No statistically significant difference was observed between these TDEs when they were used to isolate hepatocytes from liver resections or organ donor tissue on 54 hepatocyte isolations with type XI enzyme and 56 isolations using CIzyme(TM). These results show that a highly purified and defined TDE preparation can be formulated that provides excellent performance with respect to viability, yield, and functional activity of the isolated cells. In addition to reproducible formulation, these purified enzyme products have only 2-3% of the endotoxin of crude enzyme preparations. These results show that purified enzymes such as CIzyme(TM) will be a safe and effective for the isolation of human hepatocytes for clinical transplants.

Melatonin reduces dimethylnitrosamine-induced liver fibrosis in rats

Increased deposition of the extracellular matrix components, particularly collagen, is a central phenomenon in liver fibrosis. Stellate cells, the central mediators in the pathogenesis of fibrosis are activated by free radicals, and synthesize collagen. Melatonin is a potent physiological scavenger of hydroxyl radicals. Melatonin has also been shown to be involved in the inhibitory regulation of collagen content in tissues. At present, no effective treatment of liver fibrosis is available for clinical use. We aimed to test the effects of melatonin on dimethylnitrosamine (DMN)-induced liver damage in rats. Wistar albino rats were injected with DMN intraperitoneally. Following a single dose of 40 mg/kg DMN, either saline (DMN) or 100 mg/kg daily melatonin was administered for 14 days. In other rats, physiologic saline or melatonin were injected for 14 days, following a single injection of saline as control. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examination. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH) and superoxide dismutase (SOD) levels were evaluated in blood and tissue homogenates. DMN caused hepatic fibrotic changes, whereas melatonin suppressed these changes in five of 14 rats (P < 0.05). DMN administration resulted in increased hydroxyproline and MDA levels, and decreased GSH and SOD levels, whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin functions as a potent fibrosuppressant and antioxidant, and may be a therapeutic choice.

Placental stem cell correction of murine intermediate maple syrup urine disease

There is improved survival and partial metabolic correction of a mouse intermediate maple syrup urine disease (iMSUD) model after allogenic hepatocyte transplantation, confirming that a small number of enzyme-proficient liver-engrafted cells can improve phenotype. However, clinical shortages of suitable livers for hepatocyte isolation indicate a need for alternative cell sources. Human amnion epithelial cells (hAECs) share stem cell characteristics without the latter's safety and ethical concerns and differentiate to hepatocyte-like cells. Eight direct hepatic hAEC transplantations were performed in iMSUD mice over the first 35 days beginning at birth; animals were provided a normal protein diet and sacrificed at 35 and 100 days. Treatment at the neonatal stage is clinically relevant for MSUD and may offer a donor cell engraftment advantage. Survival was significantly extended and body weight was normalized in iMSUD mice receiving hAEC transplantations compared with untreated iMSUD mice, which were severely cachectic and died ≤28 days after birth. Branched chain α-keto acid dehydrogenase enzyme activity was significantly increased in transplanted livers. The branched chain amino acids leucine, isoleucine, valine, and alloisoleucine were significantly improved in serum and brain, as were other large neutral amino acids.

CONCLUSION

Placental-derived stem cell transplantation lengthened survival and corrected many amino acid imbalances in a mouse model of iMSUD. This highlights the potential for their use as a viable alternative clinical therapy for MSUD and other liver-based metabolic diseases.

Secondary causes of inflammatory bowel diseases

Inflammatory bowel diseases (IBD), conventionally consist of Crohn's disease (CD) and ulcerative colitis. They occur in individuals with high risk genotype for the disease in the setting of appropriate environmental factors. The pathogenesis of IBD involves a dysregulated autoimmune response to gut dysbiosis, which in turn is triggered due to exposure to various inciting environmental factors. But there is no clearly defined etiology of IBD and this type of disease is termed as "idiopathic IBD", "classic IBD", or "primary IBD". We reviewed the current medical literature and found that certain etiological factors may be responsible for the development of IBD or IBD-like conditions, and we consider this form of de novo IBD as "secondary IBD". Currently known factors that are potentially responsible for giving rise to secondary IBD are medications; bowel altering surgeries and transplantation of organs, stem cells or fecal microbiome. Medications associated with the development of secondary IBD include; immunomodulators, anti-tumor necrosis factor alpha agents, anti-interleukin agents, interferons, immune stimulating agents and checkpoint inhibitors. Colectomy can in some cases give rise to de novo CD, pouchitis of the ileal pouch, or postcolectomy enteritis syndrome. After solid organ transplantation or hematopoietic stem cell transplantation, the recipient may develop de novo IBD or IBD flare. Fecal microbiota transplantation has been widely used to treat patients suffering from recurrent Clostridium difficile infection but can also causes IBD flares.

New potential cell source for hepatocyte transplantation: discarded livers from metabolic disease liver transplants

Domino liver transplantation is a method used to increase the number of liver grafts available for orthotopic liver transplantation (OLT). Reports indicate that livers from patients with metabolic liver disease can be safely transplanted into select recipients if the donor's defect and the recipient's metabolic needs are carefully considered. The liver of patients with many types of metabolic liver disease is morphologically and biochemically normal, except for the mutation that characterizes that disease. Other biochemical functions normally performed by the liver are present and presumably "normal" in these hepatocytes. Hepatocytes were isolated from the liver of 35 organ donors and 35 liver tissues taken at OLT from patients with liver disease were analyzed for 9 different measures of viability and function. The data indicate that cells isolated from some diseased livers performed as well or better than those isolated from organ donors with respect to viability, cell yield, plating efficiency and in assays of liver function, including drug metabolism, conjugation reactions and ammonia metabolism. Cells from metabolic diseased livers rapidly and efficiently repopulated a mouse liver upon transplantation.

CONCLUSIONS

As with domino liver transplantation, domino cell transplantation deserves consideration as method to extend the pool of available organs and cells for transplantation.

Isolation of amniotic mesenchymal stem cells

Mesenchymal stem cells (MSCs) have the ability to differentiate into osteocytes, chondrocytes, and adipocytes and possess immunomodulatory properties. Amniotic membrane from human term placenta is a potential source of multipotent MSCs that could be useful for regenerative medicine. This unit describes a detailed and simple protocol for the isolation of amniotic mesenchymal cells. We also introduce a simple density separation technique for the purification of this cell type from possible contamination with amniotic epithelial cells.

The prevalence of hepatic granulomas in chronic hepatitis C

OBJECTIVES

Hepatic granulomas are not usual findings in chronic hepatitis C. A few studies addressing the frequency of hepatic granulomas in chronic hepatitis C reported it as less than 10%. The presence of it has been suggested to predict a favorable response to interferon treatment. Also, case reports described the development of hepatic granulomas after interferon treatment. In this study, we aimed to detect the prevalence of hepatic granulomas in chronic hepatitis C and to identify the causes other than chronic hepatitis C, if present, to search whether there is an association between the presence of granuloma and response to interferon treatment and also to see whether interferon leads to the formation of hepatic granulomas.

METHODS

Patients from 3 university clinics were included. All patients with chronic hepatitis C were determined. All patients with hepatic granulomas were screened for the other causes of hepatic granuloma with tuberculin skin test, chest X-ray and computed tomography, Venereal Disease Research Laboratory, and Brucella agglutination tests. The histologic assessment of liver biopsies was done by the same pathologist in each center.

RESULTS

A total of 725 liver biopsies of 605 patients with chronic hepatitis C were screened. In 8 patients, hepatic granulomas were detected in the initial liver biopsies. Four patients had repeat biopsies, and all had hepatic granulomas again. The prevalence of hepatic granulomas in patients with chronic hepatitis C was calculated as 1.3% (8 of 605) in reference to patient population. Presence or absence of hepatic granulomas was seemingly stable. All patients with hepatic granulomas had negative results of tuberculin skin test, Venereal Disease Research Laboratory, chest X-ray and computed tomography, and Brucella agglutination tests. All repeat biopsies were obtained after interferon (+/- ribavirin) in varying doses and duration. Four of 8 patients with hepatic granulomas were found to respond interferon therapy. No patient was found to develop hepatic granulomas after interferon therapy.

CONCLUSION

Hepatic granulomas are a rare finding in HCV infection. The presence of it does not seem to predict the response to interferon therapy. The development of hepatic granulomas during interferon therapy is not usual.

Sarcoidosis after use of interferon for chronic hepatitis C: report of a case and review of the literature

Although interferon has not been classified in the pathogenesis of sarcoidosis, it may rarely lead to this disease during treatment of chronic hepatitis C. The case of a 36-year-old woman with chronic hepatitis C who developed sarcoidosis within 10 weeks of treatment with recombinant interferon-alpha2a and ribavirin is described and all seven similar cases published in English from 1989 to 2001 are discussed.

Melatonin ameliorates methionine- and choline-deficient diet-induced nonalcoholic steatohepatitis in rats

Nonalcoholic steatohepatitis (NASH) may progress to advanced fibrosis and cirrhosis. Mainly, oxidative stress and excessive hepatocyte apoptosis are implicated in the pathogenesis of progressive NASH. Melatonin is not only a powerful antioxidant but also an anti-inflammatory and anti-apoptotic agent. We aimed to evaluate the effects of melatonin on methionine- and choline-deficient diet (MCDD)-induced NASH in rats. Thirty-two male Wistar rats were divided into four groups. Two groups were fed with MCDD while the other two groups were fed a control diet, pair-fed. One of the MCDD groups and one of the control diet groups were administered melatonin 50 mg/kg/day intraperitoneally, and the controls were given a vehicle. After 1 month the liver tissue oxidative stress markers, proinflammatory cytokines and hepatocyte apoptosis were studied by commercially available kits. For grading and staging histological lesions, Brunt et al.'s system was used. Melatonin decreased oxidative stress, proinflammatory cytokines and hepatocyte apoptosis. The drug ameliorated the grade of NASH. The present study suggests that melatonin functions as a potent antioxidant, anti-inflammatory and antiapoptotic agent in NASH and may be a therapeutic option.

N-acetylcysteine expresses powerful anti-inflammatory and antioxidant activities resulting in complete improvement of acetic acid-induced colitis in rats

High free radical production, low antioxidant capacity and excessive inflammation are well known features in the pathogenesis of inflammatory bowel disease. N-acetylcysteine (NAC) is a powerful antioxidant and a scavenger of hydroxyl radicals. Recently, NAC has also been shown to have anti-inflammatory activities in tissues. Our study objective was to investigate the effects of NAC on tissue inflammatory activities using an ulcerative colitis model induced by acetic acid (AA) in rats. Wistar rats (n = 32) were divided into four groups. AA-induced colitis was performed in two of the groups while the other two groups were injected with saline intrarectally. One of the AA-induced colitis groups and one of the control groups were administered NAC (500 mg/kg/day) intrarectally, and the other control groups were given saline. After 4 days, colonic changes were evaluated biochemically by measuring proinflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6], myeloperoxidase (MPO), malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) levels in tissue homogenates and by histopathological examination. AA caused colonic mucosal injury, whereas NAC administration suppressed these changes in the AA-induced colitis group (p < 0.001). AA-administration resulted in increased TNF-α, IL-1β, IL-6, MPO and MDA levels, and decreased GSH and SOD levels, whereas NAC reversed these effects (all p < 0.001). In conclusion, the present study proposes that intrarectal NAC therapy has a dual action as an effective anti-inflammatory and an antioxidant, and may be a promising therapeutic option for ulcerative colitis.

Improved amino acid, bioenergetic metabolite and neurotransmitter profiles following human amnion epithelial cell transplant in intermediate maple syrup urine disease mice

Orthotopic liver transplant (OLT) significantly improves patient outcomes in maple syrup urine disease (MSUD; OMIM: 248600), yet organ shortages point to the need for alternative therapies. Hepatocyte transplantation has shown both clinical and preclinical efficacy as an intervention for metabolic liver diseases, yet the availability of suitable livers for hepatocyte isolation is also limited. Conversely, human amnion epithelial cells (hAEC) may have utility as a hepatocyte substitute, and they share many of the characteristics of pluripotent embryonic stem cells while lacking their safety and ethical concerns. We reported that like hepatocytes, transplantation of hAEC significantly improved survival and lifespan, normalized body weight, and significantly improved branched-chain amino acid (BCAA) levels in sera and brain in a transgenic murine model of intermediate maple syrup urine disease (imsud). In the current report, we detail the neural and peripheral metabolic improvements associated with hAEC transplant in imsud mice, including amino acids associated with bioenergetics, the urea cycle, as well as the neurotransmitter systems for serotonin, dopamine, and gamma-aminobutyric acid (GABA). This stem cell therapy results in significant global correction of the metabolic profile that characterizes the disease, both in the periphery and the central nervous system, the target organ for toxicity in iMSUD. The significant correction of the disease phenotype, coupled with the theoretical benefits of hAEC, particularly their lack of immunogenicity and tumorigenicity, suggests that human amnion epithelial cells deserve serious consideration for clinical application to treat metabolic liver diseases.

Rapid and sensitive assessment of human hepatocyte functions

Transplantation of human hepatocytes (HTx) has gained recognition as a bridge to, or an alternative to, orthotopic liver transplantation for patients with acute liver failure or genetic defects in liver function. Although the quality of the hepatocytes used for cell transplantation is critical, no consensus exists on protocols to assess the function of hepatocytes prior to HTx. Application of this cell therapy in clinical practice could be aided by fast and reliable assays to evaluate the functional competence of isolated hepatocytes prior to clinical transplantation. Traditional assays for measuring metabolic functions in primary hepatocytes frequently involve highly technical equipment, time-consuming methods, and large numbers of cells. We describe a novel approach for the rapid assessment of the metabolic capabilities of human hepatocytes. This report details simple procedures to evaluate 11 endpoints from cells isolated from human liver that can be performed by a single operator within approximately 2 h of isolation. Longer term cultured hepatocytes were also analyzed to determine if the results from the 2-h tests were predictive of long-term hepatic function. The assays simultaneously measure five cytochrome P450 activities, one phase II activity, plating efficiency, and ammonia metabolism in addition to viability and cell yield. The assays require fewer than 20 million cells and can be completed using commonly available and inexpensive laboratory equipment. The protocol details methods that can be used in a time frame that would allow analysis of hepatic functions in freshly isolated hepatocytes prior to their use for clinical transplantation.

Changes in malondialdehyde levels in bronchoalveolar fluid and serum by the treatment of asthma with inhaled steroid and beta2-agonist

OBJECTIVE

Oxidative stress plays an important role in the pathogenesis of asthma. Recent data suggest that clinical indices of the patients with asthma may not correlate with the underlying inflammatory process. We aimed to measure the level of malondialdehyde (MDA), which is a marker of lipid peroxidation, a free radical-mediated process, before and after a well-accepted treatment of asthma.

METHODOLOGY

Nine non-smoking females and five non-smoking males with mild-moderate asthma were included. Twenty-four age- and sex-matched, non-smoking healthy people (17 females and seven males, mean age 32.1 years, range 20-59) were included for control. After initial evaluation, spirometry, bronchoscopy with bronchoalveolar lavage (BAL), and blood sample were maintained. The patients were treated with twice-daily salmeterol inhaler (100 microg/d) and fluticasone propionate inhaler (500 microg/d). One month later the investigations were repeated. Serum MDA levels before treatment were compared with both the levels after treatment and levels of controls. Malondialdehyde levels of BAL were compared before and after treatment.

RESULTS

Serum MDA level of the patient before treatment was 6.7+/-0.8 nmol/mL, significantly higher than that of healthy controls; 3.8+/-0.4, P < 0.001. One month after the treatment, serum MDA level decreased to 5.3+/-0.7 nmol/mL (P < 0.001). However, this level is still significantly higher than healthy controls (P < 0.0001). Forced expiratory volume in 1 s level of the patients increased from 2.43+/-0.79 L to 3.50+/-1.21 L after the treatment (P < 0.001).

CONCLUSION

Although treatment with beta2-agonist and corticosteroid inhalers for the duration of 1 month reduced lipid peroxidation significantly, it was still at a level significantly higher than healthy controls. The treatment may need a longer duration to improve lipid peroxidation or an alternative regimen which is more effective in controlling inflammation may be warranted.

N-acetylcysteine reduced the effect of ethanol on antioxidant system in rat plasma and brain tissue

Chronic ethanol administration is able to induce an oxidative stress in the central nervous system. N-Acetylcysteine (NAC) has antioxidant properties; as a sulphydryl donor, it contributes to the regeneration of glutathione and it acts through a direct reaction with hydroxyl radicals. In this study we investigated a possible beneficial effect of NAC on some of the free radical related parameters. Twenty four male Wistar rats were divided in to three groups and were given ethanol (Group 1), ethanol and NAC (Group 2) and isocaloric dextrose (Group 3). Ethanol and NAC were given intragastrically at doses of 6 g/kg/day and 1 g/kg/day, respectively. Our results show that chronic ethanol intake elicits statistically significant increase in MDA and NO levels and decrease in SOD and GSH levels in both plasma and brain (p < 0.001). GPx levels decreased in erythrocytes (p < 0.001). CAT activity showed significant decrease only in brain samples (p < 0.001). NAC administration effectively restores the above results to nearly normal levels. Therefore we suggest that reactive free radicals are, at least partly, involved in the ethanol-induced injury of brain cells and NAC mitigate the toxic effects of ethanol on the oxidant-antioxidant system of rat plasma and brain.

Leptin in nonalcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a prevalent condition associated with obesity and insulin resistance (IR). Leptin plays a key role in the control of energy balance, and insulin sensitivity. In this study, we aimed to examine whether serum leptin levels correlate with insulin resistance, oxidative stress parameters and the severity of histological changes in NAFLD.

METHODS

Fifty-two patients (M/F: 28/24) with no alcohol intake and biopsy-proven diagnosis of NAFLD were studied. Serum leptin levels were measured by radioimmunoassay. HOMA (homeostasis model assessment) IR index was calculated. Comparisons between the patients with NAFLD and non-alcoholic steatohepatitis (NASH) were performed using the Student's t test. Multivariate regression analysis and the area under the receiver operating characteristic (ROC) curve were used to identify the independent predictors for NASH.

RESULTS

We found no association between serum leptin, fasting insulin levels, and oxidative stress parameters. ROC curve and multiple regression analysis revealed no association between the severity of histological changes and serum leptin levels. During six months followed-up period only NASH group with elevated leptin levels had significant reductions of ALT and AST values (p = 0.03, and 0.005, respectively).

CONCLUSION

Our findings show a preventive effect of leptin against progressive liver injury in NAFLD.

Efficacy of interferon alpha-2b and lamivudine combination treatment in comparison to interferon alpha-2b alone in chronic delta hepatitis: a randomized trial

BACKGROUND AND AIM

Delta hepatitis is characterized by rapidly progressive liver disease with adverse prognosis in most patients. Patients benefit from high doses and prolonged courses of interferon (IFN) therapy; however, lamivudine as a single agent has been disappointing. Data relating to the efficacy of IFN and lamivudine in combination is limited. The aim of this study was to test the efficacy of IFN-alpha 2b and lamivudine combination treatment in comparison to IFN-alpha 2b alone in patients with chronic delta hepatitis.

METHODS

Twenty-six patients with chronic delta hepatitis were randomized into two groups. Twelve patients received IFN-alpha 2b alone (eight men, four women; mean +/- SD age: 43.83 +/- 8.57 years), and 14 patients received IFN-alpha 2b plus lamivudine combination (seven men, seven women; mean +/- SD age: 42.5 +/- 11.02 years). The dose of IFN-alpha 2b was 10 MU t.i.w. and of lamivudine was 100 mg/day. The groups were comparable in reference to serum alanine aminotransferase (ALT), aspartate aminotransferase, bilirubin, albumin levels, histological activity and stage. Four patients (33.3%) in the IFN group and two (14.3%) in the combination group had cirrhosis (P = 0.2). The duration of treatment was 48 weeks with an untreated follow-up period of at least 96 weeks (mean +/- SD, 3.1 +/- 1.9 years). A liver biopsy was performed at the end of treatment.

RESULTS

Eight patients from the IFN group and 11 from the combination group completed treatment. Serum ALT values became normal in 8/14 patients (57.1%) treated with IFN plus lamivudine and in 5/12 patients (41.7%) treated with IFN alone (P = 0.43). Serum hepatitis delta virus RNA was no longer detectable in nine of 14 (64.3%) patients treated with IFN plus lamivudine as compared to five of 12 (41.6%) patients treated with IFN alone (P = 0.024). In both groups female patients had significantly better virological response rate (P = 0.007). There was a significant improvement in histological activity in the combination group (mean decrease 5.27 +/- 1.08 score, P = 0.001), but not in the IFN group (mean decrease 1.44 +/- 1.59 score, P = 0.39). No significant improvement was observed in regards to fibrosis. Four of the 14 patients (28.6%) treated with combination therapy as compared to two of 12 patients treated with IFN (16.7%) were sustained virological responders (P = 0.47). The 5-year survival rate was 65% in the IFN group and 85% in the combination group (P > 0.05).

CONCLUSION

Interferon and lamivudine in combination is an encouraging treatment method and may be superior to IFN alone in chronic delta hepatitis.

Epidemiology, determinants, and management of AIDS cholangiopathy: A review

Diseases of the liver and biliary tree have been described with significant frequency among patients with human immunodeficiency virus (HIV), and its advanced state, acquired immunodeficiency syndrome (AIDS). Through a variety of mechanisms, HIV/AIDS has been shown to affect the hepatic parenchyma and biliary tree, leading to liver inflammation and biliary strictures. One of the potential hepatobiliary complications of this viral infection is AIDS cholangiopathy, a syndrome of biliary obstruction and liver damage due to infection-related strictures of the biliary tract. AIDS cholangiopathy is highly associated with opportunistic infections and advanced immunosuppression in AIDS patients, and due to the increased availability of highly active antiretroviral therapy, is now primarily seen in instances of poor access to anti-retroviral therapy and medication non-compliance. While current published literature describes well the clinical, biochemical, and endoscopic management of AIDS-related cholangiopathy, information on its epidemiology, natural history, and pathology are not as well defined. The objective of this review is to summarize the available literature on AIDS cholangiopathy, emphasizing its epidemiology, course of disease, and determinants, while also revealing an updated approach for its evaluation and management.