Increased reprogramming of human fetal hepatocytes compared with adult hepatocytes in feeder-free conditions

Hepatocyte transplantation has been used to treat liver disease. The availability of cells for these procedures is quite limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) may be a useful source of hepatocytes for basic research and transplantation if efficient and effective differentiation protocols were developed and problems with tumorigenicity could be overcome. Recent evidence suggests that the cell of origin may affect hiPSC differentiation. Thus, hiPSCs generated from hepatocytes may differentiate back to hepatocytes more efficiently than hiPSCs from other cell types. We examined the efficiency of reprogramming adult and fetal human hepatocytes. The present studies report the generation of 40 hiPSC lines from primary human hepatocytes under feeder-free conditions. Of these, 37 hiPSC lines were generated from fetal hepatocytes, 2 hiPSC lines from normal hepatocytes, and 1 hiPSC line from hepatocytes of a patient with Crigler-Najjar syndrome, type 1. All lines were confirmed reprogrammed and expressed markers of pluripotency by gene expression, flow cytometry, immunocytochemistry, and teratoma formation. Fetal hepatocytes were reprogrammed at a frequency over 50-fold higher than adult hepatocytes. Adult hepatocytes were only reprogrammed with six factors, while fetal hepatocytes could be reprogrammed with three (OCT4, SOX2, NANOG) or four factors (OCT4, SOX2, NANOG, LIN28 or OCT4, SOX2, KLF4, C-MYC). The increased reprogramming efficiency of fetal cells was not due to increased transduction efficiency or vector toxicity. These studies confirm that hiPSCs can be generated from adult and fetal hepatocytes including those with genetic diseases. Fetal hepatocytes reprogram much more efficiently than adult hepatocytes, although both could serve as useful sources of hiPSC-derived hepatocytes for basic research or transplantation.

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.

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.

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.

Hepatobiliary disposition of 17-OHPC and taurocholate in fetal human hepatocytes: a comparison with adult human hepatocytes

Little information is available in the literature regarding the expression and activity of transporters in fetal human liver or cultured cells. A synthetic progesterone structural analog, 17α-hydroxyprogesterone caproate (17-OHPC), is used in the prevention of spontaneous abortion in women with a history of recurrent miscarriage (habitual abortion). 17-OHPC has been reported to traverse the placental barrier and gain access to fetal circulation. In this study, the role of transporters in the disposition of 17-OHPC in fetal and adult human hepatocytes was examined. Progesterone metabolites have been reported to induce trans-inhibition of bile acid transporter, ABCB11. Thus, we investigated the effect of 17-OHPC or its metabolites on [(3)H]taurocholic acid transport in sandwich-cultured human fetal and adult hepatocytes. 17-OHPC was taken up rapidly into the cells and transported out partially by an active efflux process that was significantly inhibited by cold temperature, cyclosporine, verapamil, and rifampin. The active efflux mechanism was observed in both adult and fetal hepatocyte cultures. 17-OHPC produced a concentration-dependent inhibition of taurocholate efflux into canaliculi in sandwich-cultured adult and fetal human hepatocytes. However, given the high concentrations required to cause inhibition of these transport processes, no adverse effects would be anticipated from therapeutic levels of 17-OHPC. We also evaluated the expression of various hepatic transporters (ABCB1, ABCB4, SLCO1B1, SLCO1B3, SLCO2B1, ABCB11, SLC10A1, ABCC2, ABCC3, ABCC4, and ABCG2) in fetal and adult hepatocytes. With the exception of ABCB4, all transporters examined were expressed, albeit at lower mRNA levels in fetal hepatocytes compared with adults.

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.

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.

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.

Time course of collagen peak in bile duct-ligated rats

Background

One of the most useful experimental fibrogenesis models is the "bile duct-ligated rats". Our aim was to investigate the quantitative hepatic collagen content by two different methods during the different stages of hepatic fibrosis in bile duct-ligated rats on a weekly basis. We questioned whether the 1-wk or 4-wk bile duct-ligated model is suitable in animal fibrogenesis trials.

Methods

Of the 53 male Wistar rats, 8 (Group 0) were used as a healthy control group. Bile duct ligation (BDL) had been performed in the rest. Bile duct-ligated rates were sacrificed 7 days later in group 1 (10 rats), 14 days later in group 2 (9 rats), 21 days later in group 3(9 rats) and 28 days later in group 4 (9 rats). Eight rats underwent sham-operation (Sham). Hepatic collagen measurements as well as serum levels of liver enzymes and function tests were all analysed.

Results

The peak level of collagen was observed biochemically and histomorphometricly at the end of third week (P < 0.001 and P < 0.05). Suprisingly, collagen levels had decreased with the course of time such as at the end of fourth week (P < 0.01 and P < 0.05).

Conclusion

We have shown that fibrosis in bile duct-ligated rats is transient, i.e. reverses spontaneously after 3 weeks. This contrasts any situation in patients where hepatic fibrosis is progressive and irreversible as countless studies performed by many investigators in the same animal model.

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.

Association between bactericidal/permeability increasing protein (BPI) gene polymorphism (Lys216Glu) and inflammatory bowel disease

BACKGROUND

Increasing evidence suggests that innate immune system may have a key role in the pathogenesis of the inflammatory bowel disease (IBD). Bactericidal/permeability increasing protein (BPI) has an important role in the recognition and neutralization of gram-negative bacteria by host innate immune system. The polymorphism on BPI gene called Lys216Glu is on the suspected list of IBD pathogenesis.

METHODS

We studied the Lys216Glu polymorphism on BPI gene, in a Turkish IBD patient population. A total of 238 IBD patients; 116 Crohn's disease (CD) and 122 ulcerative colitis (UC), besides 197 healthy controls were included in this study.

RESULTS

The Glu/Glu genotype and allele frequencies were found to be statistically higher compared to healthy control group not only in CD patients [P: 0.03, OR: 1.87 (CI 95% 1.02-3.42) and P: 0.00001 (OR: 2.07 CI 95% 1.47-2.91) respectively] but also in UC patients [P: 0.0002, OR: 2.71 (CI 95% 1.53-4.80) and P: 0.00002 (OR: 2.71 CI 95% 1.53-4.80) respectively].

CONCLUSIONS

BPI polymorphism (Lys216Glu) is associated both to CD and UC. Our findings differ from the two Western European studies; one without any association and the other indicating an association only with CD. Our study is the first one reporting a novel association between BPI gene mutation (Lys216Glu) and UC.

Effects of a long-acting somatostatin analogue, lanreotide, on bile duct ligation-induced liver fibrosis in rats

BACKGROUND/AIMS

Somatostatin receptors have been shown on hepatic stellate cells, and somatostatin infusion has been shown to inhibit hepatic stellate cells activation. We aimed to test the effects of a long-acting somatostatin analogue, lanreotide, on bile duct ligation-induced liver fibrosis in rats.

METHODS

Thirty-seven Wistar rats were divided into 5 groups as follows: Group 1, bile duct ligation+lanreotide; Group 2, bile duct ligation; Group 3, sham+lanreotide; Group 4, sham; and Group 5, control group. Lanreotide-autogel (20 mg/kg/month) or saline in intraperitoneal doses was administered. Serum biochemical parameters, liver collagen level, and oxidative stress and histological parameters were determined after 28 days.

RESULTS

The tissue collagen level, biochemical parameters (AST, ALT, bilirubins, alkaline phosphatase, γ-glutamyl transpeptidase) and oxidative stress parameters (malondialdehyde, luminal, lucigenin) in the bile duct ligation groups were higher than in the sham-operated and control groups (p<0.001 for all). Lanreotide improved malondialdehyde and glutathione levels in the bile duct ligation+lanreotide group. In histopathological examination, bile duct ligation groups showed stage-3 liver fibrosis, while all the controls were normal. Lanreotide did not improve the liver fibrosis histologically or biochemically.

CONCLUSIONS

A monthly active somatostatin analogue, lanreotide, improved malondialdehyde and glutathione; however, it was not able to improve bile duct ligation-induced liver fibrosis in rats. Although lanreotide is a long-acting medication, it did not show anti-fibrotic effects in the model.

Long-term effect of interferon therapy in patients with HBeAg positive chronic hepatitis B infection

INTRODUCTION

Several studies have reported that interferon therapy increases elimination rate of HBeAg and anti-HBe seroconversion in chronic hepatitis B (CHB) patients. We aimed to evaluate long-term results of interferon-α treatment in HBeAg positive CHB patients in a country with exclusively D genotype.

METHODS

Seventy-one naive CHB patients (M/F 61/10, mean age 29±12 years, range 16-62) treated with 6 months of interferon-α 2b, 10 MU tiw and had a consequent untreated follow-up period of at least 10 years with positive response were identified and their data were reviewed. The therapy response was defined as HBeAg seroconversion with undetectable HBV-DNA. The responders were followed-up at 3-6-month intervals.

RESULTS

Twenty-eight (39%) patients achieved HBeAg seroconversion (25 within the therapy, 3 within the consequent 12 months off-treatment follow-up). The responders were followed-up with a mean period of 152 months (range 123-181). In the follow-up period, 21/25 (84%) initial responders relapsed. On the other hand, 3 patients who did not respond at the end of therapy sustained the response during follow-up. Hence 21/28 total responders relapsed (75%), either with HBeAg reversion (3, 14.3%) or HBV-DNA elevation over 2000 IU/ml (or its equivalent in other types of definitions) and ALT elevation (18, 85.7%). The sustained response was present in 7 patients (9.8%). Serious side effects precluding completion of treatment occurred in three patients (4.2%). In multivariate analysis none of the pre-treatment parameters appeared to be significant in predicting response.

CONCLUSION

Sustained response to interferon treatment is low in HBeAg positive CHB patients with genotype D.

Melatonin ameliorates liver fibrosis induced by bile-duct ligation in rats

BACKGROUND

Hepatic stellate cells, the main mediators in the pathogenesis of fibrosis, are triggered by free radicals and produce collagen. Melatonin is a powerful physiologic scavenger of hydroxyl radicals. It is also involved in the inhibitory regulation of the collagen content in tissue. There is no effective treatment available for liver fibrosis. Our objective was to evaluate the effects of melatonin on liver fibrosis induced by bile-duct ligation (BDL) in rats.

METHODS

We divided male Wistar rats (n = 32) into 4 groups. Two groups received BDL and 2 groups received sham operations. One of the BDL groups and one of the sham groups were administered melatonin (100 mg/kg/day via intraperitoneal injection), and the controls were given vehicle only. After 1 month, we biochemically evaluated the changes in hepatic fibrosis by measuring tissue collagen levels and histopathologic examination. We evaluated the levels of malondialdehyde (MDA), glutathione (GSH), luminal and lucigenin in tissue homogenates, and we studied proinflammatory cytokines in serum using commercially available kits.

RESULTS

Bile-duct ligation caused hepatic fibrotic changes, whereas melatonin suppressed these changes in 5 of 8 rats (p < 0.001). Bile-duct ligation resulted in increased collagen, MDA, luminal and lucigenin levels and decreased GSH levels, whereas melatonin reversed these effects.

CONCLUSION

We found that melatonin functions as an effective fibrosuppressant and antioxidant, and the results suggest that it can be used as a therapeutic option.

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.

Is HCV genotyping cost-effective even when the prevalences of genotypes 2 and 3 are low?

BACKGROUND/AIMS

The management of chronic hepatitis C virus (HCV) infection is costly. Genotyping determines the indication, probability of response, and duration of treatment and the dose of ribavirin. Although genotyping is accepted cost-effective, the cost of genotyping in all of the patients to find out a minority may offset the gain. The present study aimed; (1) to determine the frequency rate of HCV genotypes and (2) to compare the cost of HCV treatment tailored according to the genotype versus that planned supposing it to be genotype 1.

METHODOLOGY

Six centers were included into the study. Name, age, genotype, and serotype of each patient were entered. For genotyping, HCV-RNA was extracted by acid-guanidium-phenol-chloroform method. Cost of genotyping, HCV-RNA studies and the treatment with pegylated interferon and ribavirin was estimated. The cost was determined according to two scenarios: (A) To manage patients as if all had genotypes other than 2-3. (B) To manage them after determining the geno type. The management was assumed to be made by current guidelines.

RESULTS

The data of 834 patients were analyzed: Genotypel was predominant: 730 (87.5%). The rest was composed of G2:26 (3.1%), G3:26 (3.1%), G4:14 (1.7%), mixed: 13 (1.6%), undetermined: 25(3%). The cost of approach A (for 100 patients) was 1,718,200 USD; that of approach B (for 100 patients) was 1,671,900 USD. With genotype targeted therapy, every 100 patient would save 46,300 USD.

CONCLUSIONS

The prevalent genotype in our country is genotypel. The sum of genotypes 2 and 3 corresponds to 6%. Genotyping HCV and tailoring the treatment thereafter are cost-effective even in the countries where prevalence of these genotypes is low.

Sertraline hepatotoxicity: report of a case and review of the literature

Sertraline is a commonly prescribed selective serotonin reuptake inhibitor drug. Hepatotoxicity caused by sertraline is rare. Asymptomatic elevations in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels have been rarely reported and shortly normalize after discontinuation of the agent. We present a case of severe drug-induced hepatitis in a patient receiving sertraline. To our knowledge, this is the seventh case in the medical literature as being associated with severe hepatotoxicity. Since it is extremely rare, we do not suggest a strict laboratory monitoring. However, sertraline should be discontinued in cases with symptoms implying hepatotoxicity and the patients should be informed of the potential of this side effect.

Aorto-enteric fistula: a dilemma for the endoscopist as a rare cause of gastro-intestinal bleeding

A 78-year-old man with a history of aorta-femoral graft operation was admitted to the hospital with symptoms of syncope, melena and haematemesis. He reported several episodes of melena during the previous year for which he underwent repeated gastro-intestinal endoscopic examinations, which were unable to show the site of the gastro-intestinal bleeding. The third upper gastro-intestinal endoscopic examination disclosed a yellowish ulcerative lesion with irregular borders in the third part of the duodenum, which was considered to be a fistula, between the aorta and the duodenum. The patient underwent an explorative operation that revealed an intact aortic graft, firmly adherent to the duodenal wall, and the duodenum that was eroded in the third portion. The duodenum was transected and a duodenoduodenostomy was performed. Although re-bleeding did not occur, the patient died of sepsis eight days after the operation. Aorto-enteric fistulae can be missed due to the common practice of limiting the endoscopic examination to the second part of the duodenum and not considering them in the differential diagnosis of gastro-intestinal bleeding because of their rarity. Possibly, a number of prior endoscopic examinations may be inconclusive until a correct diagnosis is reached in most of the cases.

Acute hepatitis C: prevention and treatment

HCV can cause acute or chronic hepatitis and is a health problem all over the world. It is one of the leading causes of cirrhosis and hepatocellular carcinoma, and is a common indication for liver transplantation. Unrecognized patients with HCV infection may transmit the virus to uninfected people. The acute form of the disease leads to chronic hepatitis in the majority of cases. Since the success rate of treatment given in the chronic phase is much lower than that given in the acute phase, recognizing acute hepatitis is critical. Although HCV is less prevalent since 1990s in the Western world after improved blood-donor screening programs, needle-exchange facilities and education among intravenous drug users, it is still endemic in some regions, including African countries, Egypt, Taiwan, China and Japan. Acute HCV infection may be a challenge for the clinician; since it is often asymptomatic, detection and diagnosis are usually difficult. After an incubation period of 7 weeks (2-12 weeks), only a minority of patients (10-15%) report symptoms. The spontaneous clearance of the virus is more frequent primarily during the first 3 months of clinical onset of the disease, but may occur anytime during the 6 months of acute infection. This spontaneous resolution seems to be more frequent in symptomatic cases. Viremia persisting more than 6 months is accepted as chronic infection. The virus is transmitted more frequently through infected blood or body fluids. Detection of antibodies against HCV is not a reliable method of diagnosing acute HCV infection since the appearance of antibodies against HCV can be delayed in up to 30% of patients at the onset of symptoms. Thus, the diagnosis of acute hepatitis C relies on the qualitative detection of HCV RNA, which may appear as early as 1-2 weeks after exposure quickly followed by highly elevated alanine aminotransferase. After a follow-up period of 8-12 weeks for allowing spontaneous resolution, treatment should be initiated. Pegylated interferon monotherapy for 24 weeks seems effective, and the therapy can be individualized according to the characteristics of the patient.

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.

Pro12Ala polymorphism in the peroxisome proliferator-activated receptor-gamma (PPARgamma) gene in inflammatory bowel disease

BACKGROUND & AIMS

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) has recently been implicated as an endogenous regulator of cellular proliferation and inflammation. Impaired expression of PPAR-gamma in colonic epithelial cells in ulcerative colitis (UC) and increased expression in hypertrophic mesenteric adipose tissue in Crohn's disease (CD) have been reported. Furthermore, PPAR-gamma ligands have been shown to inhibit tissue injury associated with immune activation in UC. Any mutation in PPAR-gamma gene may be responsible for the increase in inflammatory mediators and hence the perpetuation of inflammation in inflammatory bowel disease (IBD) patients. One common polymorphism in PPAR-gamma gene is proline to alanine substitution (Pro12Ala) which results from a CCA to GCA missense substitution in codon 12 of exon 2 of the PPAR-gamma gene. In this study, we aimed to explore Pro12Ala polymorphism in PPAR-gamma gene in IBD in Turkish patients.

METHODS

69 patients with CD, 45 with UC and 100 controls of similar age and sex were studied. Genomic DNA was isolated from peripheral blood leucocytes and mutagenically separated-polymerase chain reaction (PCR) analyses were performed to determine the Pro12Ala polymorphism of the PPAR-gamma gene.

RESULTS

We observed no significant differences in the frequency of the Pro12Ala polymorphism in the PPAR-gamma gene among subjects with CD, UC and controls (15.9%, 15.5% and 13%, respectively, p>0.05).

CONCLUSION

These results suggest that Pro12Ala polymorphism in the PPAR-gamma gene relates neither to the risk of the development of inflammatory bowel disease nor to the clinical subtypes of CD in the Turkish population.