Serum leptin, soluble leptin receptor, free leptin index and bone mineral density in patients with primary biliary cirrhosis

BACKGROUND/AIM

The pathophysiology of osteoporosis in chronic liver diseases is unknown. Recent data suggest that serum leptin is associated with bone mineral density (BMD). In animal studies leptin was found to be a potent inhibitor of bone formation. We investigated the relationship between serum leptin levels, soluble leptin receptor (sOB-R), free leptin index (FLI) and BMD in patients with primary biliary cirrhosis (PBC).

PATIENTS AND METHODS

Ninety-four female patients with PBC were included in this study; 122 healthy women served as controls. Serum leptin levels were measured by radioimmunoassay, sOB-R by enzyme-linked immunosorbent assay. BMD was measured by dual energy X-ray absorptiometry in the lumbar spine and femoral neck.

RESULTS

Serum leptin was significantly lower in patients with PBC compared with healthy controls. No difference was found between the body mass index (BMI) of patients and controls. There was a strong positive correlation between leptin and BMI. In PBC no association was found between leptin, sOB-R and liver function tests, histological stages or the presence of osteoporosis. Osteoporosis was present in 38 patients. A positive correlation was found between serum leptin and femoral neck z-score even after adjustment for BMI, whereas serum sOB-R correlated inversely with the serum leptin level. There was no difference in FLI between the subgroups of PBC patients according to the stages of the disease.

CONCLUSIONS

We found a lower serum leptin level and a higher sOB-R in patients with PBC, which could not be explained by the difference in BMI. As leptin was associated with BMD, it may be hypothesized that leptin is involved in the complex regulation of bone metabolism in PBC.

Synthesis and biological studies of nociceptin derivatives containing the DTPA chelating group for further labeling with therapeutic radionuclides

Nociceptin is an endogenous anti-opiate heptadecapeptide primarily interacting with the nociceptin (NOP) receptor. This neuropeptide-receptor system is involved in pain regulation, tolerance to and dependence on opiates as well as many other physiological and pathophysiological events. The role and mechanisms of nociceptin in pathological conditions is not clearly known yet. In an attempt to have a radiopharmaceutical labeled either with 99mTc or (111)In, we incorporated diethylenetriaminepentaacetic acid (DTPA) as chelator into the structure of [Arg14,Lys15]nociceptin(1-17)-NH2 at the epsilon-amino group of Lys15. Such a radiopeptide may be useful in imaging for diagnostical purposes. Preparation of the peptide ligands was carried out by solid phase synthesis. Two peptides containing DTPA were obtained and purified. The products were [Arg14,Lys(DTPA)15]nociceptin(1-17)-NH2 and its cross-linked dimer on the basis of mass spectrometric analysis. In (115)In3+ binding experiments the conjugates exhibited preserved indium ion chelating properties, indicating the potential use of radiolabeled DTPA-nociceptin derivatives as radiopharmaceutical. Biological properties of these compounds were studied in rat brain membrane preparations by radioligand binding, functional biochemical [35S]GTPgammaS binding assays and mouse vas deferens (MVD) bioassay. Besides the similar in vitro binding characteristics to nociceptin receptor, both of the DTPA-chelated compounds were more potent and efficient than nociceptin in functional biochemical and mouse vas deferens bioassays. Our further aim is to radiolabel these compounds in order to get a radiopharmaceutical which can be used diagnostically.

Genotype-phenotype correlations for a wide spectrum of mutations in the Wilson disease gene (ATP7B)

Wilson disease (WND) is caused by mutations in the ATP7B gene and exhibits substantial allelic heterogeneity. In this study we report the results of molecular analyses of 20 WND families not described previously. When combined with our prior results, the cohort includes 93 index patients from 69 unrelated families. Twenty different mutations accounted for 86% of the WND chromosomes. The most frequent were p.H1069Q (35%), p.R969Q (12%), c.2530delA (7%), p.L936X (7%), p.Q289X (7%), and p.I1148T (3%). We also present here a detailed phenotypic assessment for patients whose molecular result was previously reported. Thirty cases were homozygous for 9 different mutations, 13 of which were homozygous for p.H1069Q, and 7 for p.R969Q. Mutations p.H1069Q and p.R969Q appeared to confer a milder disease as patients showed disease onset at a later age, and were associated with milder severity when found in trans with severe mutations. Predicted nonsense and frameshift mutations were associated with severe phenotypic expression with earlier disease onset and lower ceruloplasmin values. WND can be treated by copper-chelation therapy, particularly if the disease is diagnosed before irreversible tissue damage occurs. Our results on the effect of predicted nonsense and frameshift mutations are especially important for early medical intervention in presymptomatic infants and children with these genotypes.

From bases to basis: linking genetics to causation in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a multifactorial autoimmune disease with inherited and environmental components in pathogenesis. It is exceptional among autoimmune diseases in showing strong heritability according to familial occurrence and monozygotic twins concordance, yet with weak associations with the usual genetic risk elements for autoimmunity, such as the HLA alleles. Among the latter, there is risk (at least in some populations) conferred by HLA DRB1*08 and possibly some protection by DRB1*11. However, the inconsistency among studies on HLA is surprising, given that PBC is a relatively homogenous disease entity. Among non-HLA genes, some studies implicate polymorphisms of genes for cytotoxic T-lymphocyte antigen-4, interleukin-2, or interleukin-10; polymorphisms of the vitamin D receptor could synergize with low sunlight exposure to create deficiency of the immunoregulatory factor, activated vitamin D. A new lead is available from the finding in female subjects with PBC of an increase in the degree of monosomy of the X chromosome that is presumed to carry immune response genes. A further suggested source of inquiry is the apparent protection of African-American women from PBC. Finally, data on inheritance should be sought in PBC by descent methodology, rather than by cross-sectional association studies in cases and control subjects, and based on analysis of a large number of families with an affected member through a worldwide effort.

Toll-like receptor 4 and NOD2/CARD15 mutations in Hungarian patients with Crohn's disease: phenotype-genotype correlations

AIM

To determine common NOD2/CARD15 mutations and TLR4 D299G polymorphism in Hungarian patients with CD.

METHODS

A total of 527 unrelated patients with CD (male/female: 265/262, age: 37.1 (SD 7.6) years) and 200 healthy subjects were included. DNA was screened for possible NOD2/CARD15 mutations by denaturing high-performance liquid chromatography (confirmed by direct sequencing). TLR4 D299G was tested by PCR-RFLP.

RESULTS

NOD2/CARD15 mutations were found in 185 patients (35.1%) and in 33 controls (16.5%, P<0.0001). SNP8/R702W (10.8% vs 6%, P = 0.02), SNP13/3020insC (19.4% vs 5%, P<0.0001) and exon4 R703C (2.1% vs 0%, P = 0.02) mutations were more frequent in CD, while the frequency of SNP12/G908R was not increased. The frequency of TLR4 D299G was not different (CD: 9.9% vs controls: 12.0%). Variant NOD2/CARD15 allele was associated with an increased risk for CD (OR(het) = 1.71, 95%CI = 1.12-2.6, P = 0.0001, OR(two-risk alleles) = 25.2, 95%CI = 4.37-8, P<0.0001), early disease onset (carrier: 26.4 years vs non-carrier: 29.8 years, P = 0.0006), ileal disease (81.9% vs 69.5%, OR = 1.99, 95%CI = 1.29-3.08, P = 0.02, presence of NOD2/CARD15 and TLR4: 86.7% vs 64.8%), stricturing behavior (OR = 1.69, 95%CI = 1.13-2.55, P = 0.026) and increased need for resection (OR=1.71, 95%CI: 1.13-2.62, P = 0.01), but not with duration, extra-intestinal manifestations, familial disease or smoking. TLR4 exhibited a modifier effect: age of onset in wt/TLR4 D299G carriers: 27.4 years vs NOD2mut/TLR D299G: 23 years (P = 0.06), in NOD2mut/wt: 26.7 years.

CONCLUSION

These results confirm that variant NOD2/CARD15 (R702W, R703C and 3020insC) alleles are associated with earlier disease onset, ileal disease, stricturing disease behavior in Hungarian CD patients. In contrast, although the frequency of TLR4 D299G polymorphism was not different from controls, NOD2/TLR4 mutation carriers tended to present at earlier age.

Serum osteoprotegerin is increased in Crohn's disease: a population-based case control study

BACKGROUND

There is a potential interface between osteoporosis and the chronic inflammation of inflammatory bowel disease (IBD), and the osteoprotegerin (OPG)/receptor for activated nuclear factor-kappaB (RANK)/RANK ligand (RANKL) signaling pathway may be an important mediator, although data are limited.

METHODS

We conducted a population-based case-control seroassay study to look for alterations in serum OPG and soluble RANKL (sRANKL). The study population included IBD patients who were 18 to 50 years old with Crohn's disease (CD; n = 287) or ulcerative colitis (UC; n = 166), age-matched healthy controls (n = 368), and nonaffected siblings of IBD patients (n = 146). Serum OPG and sRANKL were measured by enzyme-linked immunoassay. Sex-specific reference ranges were derived from the healthy controls.

RESULTS

Analysis of variance (ANOVA) confirmed significant group differences in women for mean serum OPG (P = 0.018). CD women had higher values of OPG than UC women (P = 0.028) or healthy controls (P = 0.045), whereas the other groups were similar. OPG levels were above the reference range in 13/173 (8%) of CD women, exceeding the expected proportion (P = 0.032). In contrast, no differences in OPG were seen in men between controls, CD, or UC. Estrogen use in women (P = 0.000002) and corticosteroid use in men (P = 0.026) were associated with higher OPG levels. In multivariate analysis, CD diagnosis (P = 0.031) and estrogen use (P = 0.000002) were independently associated with higher OPG levels. No group differences were seen in mean serum sRANKL measurements.

CONCLUSIONS

An OPG:sRANKL imbalance with OPG exceeding sRANKL should inhibit osteoclastogenesis and promote bone formation. CD is associated with increased fracture risk, and possibly, the paradoxically higher OPG is a counterregulatory response to factors such as inflammatory cytokines, promoting high bone turnover. Alternatively, elevated OPG in CD may reflect T-cell activation.

Osteoprotegerin and RANKL in alcoholic liver cirrhosis

BACKGROUND/AIMS

The mechanisms leading to osteoporosis in alcoholic liver disease remain poorly understood. Recently identified soluble circulating osteoprotegerin (OPG), is the osteoclastogenesis inhibitory factor. It acts as a decoy receptor for osteoclast activating factor, receptor activator of nuclear factor-kappaB ligand (RANKL), and impairs osteoclast function. The aim of our study was to investigate the OPG/RANKL system in alcoholic cirrhotic patients and their correlation with biochemical marker of bone turnover.

PATIENTS AND METHODS

Serum OPG, RANKL, osteocalcin (OC), C-terminal cross-linking telopeptide of type I collagen (CTX-I), bone alkaline phosphatase activity (bALP), and urinary hydroxyproline were measured in 30 patients with alcoholic cirrhosis, and in 20 age- and sex-matched healthy controls.

RESULTS

OPG levels were significantly increased in patients with alcoholic cirrhosis compared with healthy subjects (5.9 pmol/l, range 2.7-9.0 vs 4.1 pmol/l, range 1.2-6.6; P < 0.001). RANKL levels were significantly higher in patients with cirrhosis (0.48 pmol/l, range 0.01-1.34) than in healthy subjects (0.11 pmol/l, range 0.01-0.90). There was a positive correlation between serum OPG and RANKL (r = 0.37; P < 0.001), bALP (r = 0.66; P < 0.001) and urinary hydroxyproline (r = 0.51; P < 0.05) but not with OC and CTX-I.

CONCLUSIONS

OPG might partly represent a compensating mechanism to the negative balance of bone remodelling in patients with alcoholic cirrhosis.

Plasma nociceptin levels are reduced in migraine without aura

It was demonstrated that both nociceptin, a novel opioid neuropeptide, and its receptor are present in trigeminovascular neurons. In an animal model nociceptin dose-dependently inhibited neurogenic dural vasodilatation. These results suggest that nociceptin may be involved in neurovascular headaches such as migraine. To test this hypothesis, we studied circulating nociceptin levels in 18 patients suffering from migraine without aura and in 24 controls. Headache-free migraineurs had significantly lower nociceptin levels than controls (5.79 +/- 1.82 vs. 9.74 +/- 2.43 pg/ml, P < 0.0001, Student's t-tests). Nociceptin levels were further reduced in six patients studied in the first 3 h of typical migraine attacks (1.04 +/- 0.17 pg/ml). Nociceptin levels correlated with the frequency of attacks in this group of migraineurs. Lower interictal nociceptin levels may contribute to a defective regulation of trigeminovascular neurons in migraineurs which might be important in the pain process of migraine.

Toll-like receptor 4 and NOD2/CARD15 mutations in Hungarian patients with Crohn's disease: phenotype-genotype correlations

AIM

To determine common NOD2/CARD15 mutations and TLR4 D299G polymorphism in Hungarian patients with CD.

METHODS

A total of 527 unrelated patients with CD (male/female: 265/262, age: 37.1 (SD 7.6) years) and 200 healthy subjects were included. DNA was screened for possible NOD2/CARD15 mutations by denaturing high-performance liquid chromatography (confirmed by direct sequencing). TLR4 D299G was tested by PCR-RFLP.

RESULTS

NOD2/CARD15 mutations were found in 185 patients (35.1%) and in 33 controls (16.5%, P<0.0001). SNP8/R702W (10.8% vs 6%, P = 0.02), SNP13/3020insC (19.4% vs 5%, P<0.0001) and exon4 R703C (2.1% vs 0%, P = 0.02) mutations were more frequent in CD, while the frequency of SNP12/G908R was not increased. The frequency of TLR4 D299G was not different (CD: 9.9% vs controls: 12.0%). Variant NOD2/CARD15 allele was associated with an increased risk for CD (OR(het) = 1.71, 95%CI = 1.12-2.6, P = 0.0001, OR(two-risk alleles) = 25.2, 95%CI = 4.37-8, P<0.0001), early disease onset (carrier: 26.4 years vs non-carrier: 29.8 years, P = 0.0006), ileal disease (81.9% vs 69.5%, OR = 1.99, 95%CI = 1.29-3.08, P = 0.02, presence of NOD2/CARD15 and TLR4: 86.7% vs 64.8%), stricturing behavior (OR = 1.69, 95%CI = 1.13-2.55, P = 0.026) and increased need for resection (OR=1.71, 95%CI: 1.13-2.62, P = 0.01), but not with duration, extra-intestinal manifestations, familial disease or smoking. TLR4 exhibited a modifier effect: age of onset in wt/TLR4 D299G carriers: 27.4 years vs NOD2mut/TLR D299G: 23 years (P = 0.06), in NOD2mut/wt: 26.7 years.

CONCLUSION

These results confirm that variant NOD2/CARD15 (R702W, R703C and 3020insC) alleles are associated with earlier disease onset, ileal disease, stricturing disease behavior in Hungarian CD patients. In contrast, although the frequency of TLR4 D299G polymorphism was not different from controls, NOD2/TLR4 mutation carriers tended to present at earlier age.

The changes in circulating osteoprotegerin after hormone therapy in postmenopausal women and their relationship with oestrogen responsiveness on bone

OBJECTIVE

Oestrogen replacement reduces the increased rate of bone remodelling after the menopause. Osteoprotegerin (OPG) is a negative regulator of osteoclast-mediated bone resorption. In vitro studies have shown that oestrogen stimulates OPG production. However, the role of OPG in physiological bone remodelling and its regulation by oestrogen in vivo remain controversial. In this study, we analysed the association between changes in serum OPG levels and bone turnover status before and after hormone therapy (HT) in healthy postmenopausal women.

PATIENTS AND MEASUREMENTS

Ninety-nine healthy postmenopausal women of Korean ethnicity, aged 42-64 years (52.3 +/- 4.9 years, mean +/- SD) were enrolled in our study. Serum OPG levels were assessed by a highly sensitive sandwich-type enzyme immunoassay. Serum concentrations of osteocalcin (OC) and carboxyterminal telopeptides (CTx) were determined by electrochemiluminescence immunoassays. Bone mineral density (BMD) at the lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry (DEXA).

RESULTS

Baseline levels of OPG correlated neither a the bone formation marker, serum OC, nor with a bone resorption marker, serum CTx. No significant association of baseline OPG was found with baseline BMD measured at the lumbar spine and femoral neck. Serum OPG levels measured after 3 months and 1 year of HT decreased significantly compared to baseline (P < 0.001 in both). The changes in circulating OPG at 3 months of HT correlated with the changes in both serum OC (r = 0.226, P = 0.029) and serum CTx (r = 0.214, P = 0.038) at 3 months after HT. However, there was no significant association between the changes in circulating OPG after 3 months of HT and BMD values of the lumbar spine or femoral neck after 1 year of HT.

CONCLUSIONS

Our results suggest that baseline OPG levels do not reflect bone turnover status and that serial measurements of serum OPG after HT are not a useful predictor of the long-term effects of oestrogen on bone density. The decrease in serum concentrations of OPG after HT may occur to compensate for the action of oestrogen in suppressing bone resorption.

Genetic Hypercalciuria

Hypercalciuria is an important, identifiable, and reversible risk factor in stone formation. The foremost and most fundamental step in dissecting the genetics of hypercalciuria is understanding its pathophysiology. Hypercalciuria is a complex trait. This article outlines the various factors that compromise the attempt to dissect the genetics of hypercalciuria, summarizes the clinical and experimental monogenic causes of hypercalciuria, and outlines the initial results from attempts in studying polygenic hypercalciuria. Finally, the problem is set in perspective of the current database, technologic advances and limitations are highlighted, and prospects of further advances in the field are speculated upon.

NOD2/CARD15 gene polymorphism in patients with inflammatory bowel disease: Is Hungary different?

AIM: To analyse the impact of NOD2/CARD15 mutations on the clinical course of Crohn’s disease patients from an eastern European country (Hungary).

METHODS: We investigated the prevalence of the three common NOD2/CARD15 mutations (Arg702Trp, Gly908Arg, 1007finsC) in 148 patients with Crohn’s disease, 128 patients with ulcerative colitis and 208 controls recruited from the University of Szeged, Hungary. In patients with Crohn’s disease, the prevalence of NOD2/CARD15 mutations was correlated to the demographical and clinical parameters.

RESULTS: In total, 32.4% of Crohn’s disease patients carried at least one mutant allele within NOD2/CARD15 compared to 13.2% of patients with ulcerative colitis (P = 0.0002) and to 11.5% of controls (P<0.0001). In Crohn’s disease patients, the allele frequencies for Arg702Trp, Gly908Arg and 1007finsC were 7.1%, 3.0% and 10.8% respectively. Interestingly, only the 1007finsC mutation was associated with a distinct clinical phenotype. The patients positive for the 1007finsC mutation suffered more frequently from stenotic disease (P = 0.008). Furthermore, 51.9% of patients positive for the 1007finsC mutation underwent a surgical resection within the ileum compared to only 17.4% of patients without the 1007finsC mutation (P = 0.001). With respect to the other two mutations (Arg702Trp and Gly908Arg), no associations were found with all investigated clinical parameters.

CONCLUSION: NOD2/CARD15 mutations are frequently found in Crohn’s disease patients from Hungary. The 1007finsC mutation is associated with stenotic disease behaviour and frequent ileal resections.

Mucocele of the appendix: an unusual cause of lower abdominal pain in a patient with ulcerative colitis. A case report and review of literature

The authors report the case of a 60-year-old male patient. In November 2001 he developed intestinal symptoms of bloody diarrhea and abdominal pain. Colononoscopy and biopsy established the diagnosis of ulcerative colitis (proctosigmoiditis). The disease activity was moderate at the beginning. No significant laboratory alterations were found (including CEA, CA19-9), and mesalazine was started orally. He was in remission until November 2003, when he was admitted to our Outpatient Clinic for upper and right lower abdominal pain and bloody diarrhea. Colonoscopy found proctosigmoiditis with a moderate activity, gastroscopy revealed chronic gastritis, laboratory data was normal. Treatment was amended with mesalazine clysma and methylprednisolone (16 mg) orally. Symptoms ameliorated; however, right lower abdominal pain persisted. US and CT examination demonstrated a pericecal cystic mass (11 cm x 3.5 cm). At first pericecal abscess was suspected, as the previous US examination (6 mo earlier) had revealed normal findings. Fine needle aspiration was performed. Cytology confirmed the diagnosis of mucocele. The patient underwent partial cecum resection and extirpation of the mucocele. He recovered well and the final histology revealed a cystadenoma of the appendix. Follow up was started. The patient is now free of symptoms. Although primary adenocarcinoma of the appendix is uncommon, the authors emphasize that preoperative diagnosis of an underlying malignancy in a mucocele is important for patient management; however, it is difficult on imaging studies.

Rapid detection of mutations in Wilson disease gene ATP7B by DNA strip technology

Wilson disease leads to severe hepatic and neurological pathology resulting from cellular copper overload in the respective tissue. Although the affected gene, ATP7B, has been identified, genetic testing is challenging, time-consuming and expensive. Here we describe the development and use of a novel diagnostic test for four frequent mutations (M769V, W779X, H1069Q and P1134P-fs) found in Germany and many other countries in Europe. The test is based on multiplex polymerase chain reaction and DNA strip technology and was found to be highly sensitive and specific, as well as timely and cost-effective. We conclude that this test is a useful and reliable tool to screen Wilson disease patients and their family members for these mutations and may facilitate diagnosis in this complex disease.

Management of extraintestinal manifestations and other complications of inflammatory bowel disease

The past 18 months have seen many studies of the prevalence, pathogenesis, and treatment of the extraintestinal manifestations of inflammatory bowel disease (IBD). Inhibitors of tumor necrosis factor alpha have shown effectiveness in randomized trials for the treatment of spondyloarthropathies and ocular manifestations. Open-label studies suggest that these agents may be effective for pyoderma gangrenosum as well. The epidemiology of primary sclerosing cholangitis (PSC), and its relationship to IBD, is becoming clearer. Colorectal neoplasia in PSC remains an important clinical problem. Osteoporosis occurs more commonly in IBD, but the relative importance of corticosteroid use versus underlying chronic bowel inflammation as risk factors remains controversial. Chromoendoscopy may be an important means to improve detection of colorectal neoplasia in IBD. Observational studies suggest that prolonged use of aminosalicylates is associated with decreased risk of neoplasia, but data are conflicting. A randomized trial of ursodeoxycholic acid in PSC showed decreased risk of colorectal neoplasia in patients receiving the drug relative to those on placebo.

Clinical significance of carcinoembryonic antigen detection in rectal cancer patients with total mesorectal excision

AIM: To detect the carcinoembryonic antigen (CEA) in rectal cancer patients with total mesorectal excision (TME), and to prove the significance of TME in the treatment of rectal cancer.

METHODS: Pathological specimens were sellected from tissues of cancer, distal mesorectal margin (DMM), circumferential resection margin (CRM) and outer pelvic fascia in rectal cancer (n = 52) patients with TME. CEA was detected in these specimens using immunohistocheminical method, and the data were analyzed with SPSS software.

RESULTS: CEA expression was significantly higher in tissues of rectal cancer (47/52) than that in normal tissuess (2/20). There was significant difference between them (P < 0.001). CEA expression also existed in tissue of CRM (8/52). However, no CEA expression was observed in tissues of DMM and outer pelvic fascia.

CONCLUSION: CEA is highly expressed in tissues of rectal cancer. This provides scientific evidence for TME in the treatment of rectal cancer.

Pathophysiology and clinical features of Wilson disease

Wilson disease is an autosomal recessive inherited disorder of copper metabolism resulting in pathological accumulation of copper in many organs and tissues. ATP7B is the gene product of the Wilson disease gene located on chromosome 13 and resides in hepatocytes in the trans-Golgi network, transporting copper into the secretory pathway for incorporation into apoceruloplasmin and excretion into the bile. Mutations of the gene result in impaired trafficking of copper in and through the hepatocytes. More than 200 mutations of Wilson disease gene were found, the most common ones being H1069Q (in Europe) and R778L (in Asia). Wilson disease may present under a variety of clinical conditions, commonly as liver and/or neuropsychiatric disease. The pathogenesis of hepatic and neurologic Wilson disease is a direct consequence of copper accumulation. Presence of copper causes oxidative stress resulting in cell destruction. The diagnosis of Wilson disease requires a combination of a variety of clinical symptoms, biochemical tests, and detection of gene mutations, which are the basis of a score proposed by a group of international experts. Initial treatment for symptomatic patients should include a chelating agent (penicillamine or trientine). Treatment of presymptomatic patients or maintenance therapy can also be accomplished with zinc.

Strictureplasty

BACKGROUND

Advances in the use of bowel-sparing surgery for Crohn's disease have led to the development of strictureplasty as an important technique to conserve small bowel length and reduce morbidity associated with malabsorption.

METHODS

A literature review of long-term studies on strictureplasty was undertaken, and evidence of its safety and efficacy was evaluated.

RESULTS

The safety and efficacy of strictureplasty is confirmed in retrospective studies carried out over a period of 5-10 years, particularly when employed in patients at risk of short bowel syndrome, but certain questions regarding bowel function and disease activity after surgery remain unanswered. There is also concern that diseased tissue is left in situ after strictureplasty; this tissue has the potential for malignant transformation in the long term.

CONCLUSION

Strictureplasty has been used in surgery for Crohn's disease for the past 25 years. Studies have proven its efficacy in the treatment of carefully selected patients at risk of malabsorption owing to short bowel syndrome.

The H1069Q mutation in ATP7B is associated with late and neurologic presentation in Wilson disease: results of a meta-analysis

BACKGROUND AND AIMS

Wilson disease is an hereditary disorder of copper metabolism, caused by mutations in the ATP7B gene, and leading to hepatic or neurologic disease. We examined whether H1069Q, the most common ATP7B mutation, is associated with a specific phenotype.

METHODS

Genotyping results in 70 Dutch patients were related to clinical presentation. Subsequently a meta-analysis for genotype-phenotype correlation was performed on all patients available from literature, combined with the current Dutch group, a total of 577 patients.

RESULTS

The Dutch patients homozygous or heterozygous for the H1069Q mutation presented more frequently with neurologic disease (63% and 43% vs. 15%), and at a later age (20.9 and 15.9 vs. 12.6 years) than patients without the H1069Q mutation. In the meta-analysis the odds-ratio for neurologic presentation in homozygous or heterozygous H1069Q vs. non-H1069Q patients was 3.50 (95% CI 2.01-6.09) and 2.13 (95% CI 1.18-3.83), respectively. Age at presentation was 21.1, 19.2 and 16.5 years, respectively, corresponding to a weighted mean difference (WMD) of 4.41 (95% CI 1.56-7.26) for homozygous H1069Q vs. heterozygous patients and 6.68 (95% CI 4.33-9.38) for homozygous H1069Q vs. non-H1069Q patients.

CONCLUSIONS

Our results indicate that the H1069Q mutation is associated with a late and neurologic presentation.

Thromboembolism--an important manifestation of inflammatory bowel disease

Thromboembolism is an extraintestinal manifestation and an important cause of mortality in inflammatory bowel disease (IBD). The risk of thromboembolism appears to be multifactorial and related to mucosal inflammatory activity in most patients. Various laboratory markers such as thrombin activatable fibrinolysis inhibitor (TAFI) levels have been linked with thrombophilia in IBD but no single laboratory marker has emerged with sufficient predictive value to identify patients at particular risk. Prospective multifactorial analyses will be required; in the interim, clinicians must be vigilant and address common risk factors for thromboembolism in all patients with IBD.

Atopic manifestations are more common in patients with Crohn disease than in the general population

BACKGROUND

The role of TNF-alpha in Crohn disease is now well established and anti-TNF-alpha is frequently used as a second- or third-line treatment. Tumor necrosis factor-alpha (TNF-alpha) is traditionally associated with macrophages but has recently also been found in mast cells of the ileal wall in patients with Crohn disease. As it is well known that mast cells and TNF-alpha play important roles in atopic manifestations like asthma, allergic rhinitis; and eczema the aim of this study was to investigate whether these are seen more commonly in Crohn patients than in the general population.

METHODS

Patients with Crohn disease (n = 308), aged 18-50 years, living in the Linköping region in southeast Sweden, were asked to answer a questionnaire regarding the presence of any kind of atopic manifestations. The questionnaire was also sent to 930 controls collected from the Southeastern Region Population Registry. The controls were matched according to age, sex, and place of residence.

RESULTS

The response rate among the Crohn patients was 91% (280/308) and among controls 84% (779/930). Eczema was a significantly more frequent manifestation, being almost twice as common in Crohn patients (27%) as in the general population (16%). Adjustment by logistic regression for place of residence, gender, age and coexistence of any other atopic manifestation did not change the odds ratios significantly.

CONCLUSION

Atopic manifestations as a group, and eczema as a single manifestation, are significantly more frequent in Crohn patients than in the general population.

Insulin-like growth factor I gene microsatellite repeat, collagen type Ialpha1 gene Sp1 polymorphism, and bone disease in primary biliary cirrhosis

BACKGROUND

Genetic factors have been implicated in the pathogenesis of osteoporosis, a common disorder in primary biliary cirrhosis. Insulin-like growth factor I (IGF-I) gene microsatellite repeat polymorphism was found to be associated with osteoporosis in some studies, and collagen-Ialpha1 (COLIA1) Sp1 s allele was associated with lower bone mineral density in primary biliary cirrhosis. IGF-I treatment restored osteopenia and reduced fibrogenesis in experimental cirrhosis. We investigated IGF-I and COLIA1 gene polymorphisms and bone mineral density in Hungarian primary biliary cirrhosis patients.

PATIENTS AND METHODS

Seventy female patients with primary biliary cirrhosis were enrolled (mean age 57.6 years, range 37-76 years; all anti-mitochondrial antibody M2-positive; stage II-IV). One hundred and thirty-nine age-matched female subjects served as controls (mean age 55.9 years, range 43-72 years). COLIA1 and IGF-I polymorphisms were determined by polymerase chain reaction. Bone mineral density was measured by dual-energy X-ray absorptiometry in the lumbar spine and femoral neck.

RESULTS

The IGF-I was not different between primary biliary cirrhosis patients and controls. The genotype frequency of COLIA1 polymorphism was also not different between primary biliary cirrhosis patients and controls. However, the s allele was significantly less frequent in patients with primary biliary cirrhosis. Osteoporosis was detected in 22 patients. The IGF-I 192/192 genotype was associated with higher femoral-neck z-scores compared with other genotypes.

CONCLUSION

In contrast to previous studies, the s allele was less frequent in patients with primary biliary cirrhosis, and its presence was not associated with bone mineral density. Since IGF-I polymorphism was associated with bone mineral density, it may be hypothesised that not COLIA1 but IGF-I together with other genetic and environmental factors may be involved in the complex regulation of bone mineral density in primary biliary cirrhosis.

Cholestatic syndromes

PURPOSE OF REVIEW

This review highlights recent developments in the molecular pathogenesis of cholestasis as well new aspects of pathogenesis and management of clinical cholestatic disorders.

RECENT FINDINGS

Highlights include the role of nuclear receptors including FXR ligands as potential therapeutic agents, new genetic defects for pediatric cholestasis and sclerosing cholangitis, and novel infections and environmental agents as etiologies for primary biliary cirrhosis. Important clinical studies have been published in the area of pediatric cholestatic syndromes, intrahepatic cholestasis of pregnancy, primary biliary cirrhosis, primary and secondary sclerosing cholangitis, cholestasis of sepsis, viral cholestatic syndromes, and drug-induced cholestasis.

SUMMARY

These advances continue to improve understanding of the pathophysiology, diagnosis, and management of cholestatic liver disease.

Osteoprotegerin and RANKL in the pathogenesis of thalassemia-induced osteoporosis: new pieces of the puzzle

Osteoporosis represents an important cause of morbidity in adult thalassemic patients, and its pathogenesis has not, as yet, been completely clarified. In our study, we observed that thalassemic patients showed a significantly lower OPG/RANKL ratio than normal subjects. These data are extremely important for the possible therapeutic use of RANKL antagonists such as OPG in thalassemia-induced osteoporosis.

INTRODUCTION

Osteoporosis represents an important cause of morbidity in adult thalassemic patients who display increased fracture risk. The etiology of this bone disease is multifactorial, but it is thought that the main role is played by hypogonadism. The mechanisms by which the skeletal effects of sex steroids are mediated are still not fully understood. Recently, two new cytokines, osteoprotegerin (OPG) and RANKL, have been implicated in the pathogenesis of postmenopausal osteoporosis and other metabolic bone diseases. Thus, the aim of this study was to characterize the possible role of the OPG/RANKL system in thalassemia-related bone loss.

MATERIALS AND METHODS

We measured, in 30 thalassemic patients and in 20 healthy control subjects, serum OPG and RANKL levels, and determined their correlations with bone turnover markers, BMD, sex steroid levels, erythropoietin, and hemoglobin.

RESULTS

Thalassemic patients had an unbalanced bone turnover with an increased resorption phase (shown by high levels of pyridinium cross-links) and a decreased neoformation phase (shown by the slightly low levels of osteocalcin). Moreover, they displayed lower BMD values than controls both at the lumbar and femoral level. As far as the OPG/RANKL system is concerned, thalassemic patients showed no differences in plasma levels of OPG compared with controls, and significantly higher plasma levels of RANKL, with a consequent significantly lower OPG/RANKL ratio.

CONCLUSIONS

Our data suggest that, in thalassemic patients, an altered modulation of the OPG/RANKL system, resulting in increased expression of RANKL by stromal or osteoblastic cells, could contribute to the enhanced osteoclastic bone resorption and bone loss characteristic of these patients.

Characterization of the molecular defect in the ATP7B gene in Wilson disease patients from Yugoslavia

Wilson disease (WD) is an autosomal recessive disorder of copper metabolism resulting from the absence or dysfunction of a copper transporting P-type ATPase (ATP7B). Approximately 150 mutations of the ATP7B have been identified to date. In this paper, we report the results of molecular characterization and genotype-phenotype analysis, which we have carried out on 35 patients from Yugoslavia affected by WD. Using single-strand conformational polymorphism (SSCP) followed by direct sequencing, we characterized the molecular defect in 80% of WD chromosomes and found 11 different mutations, three of which are novel. The most common mutations that accounted for the molecular defect in 71.3% of WD chromosomes were H1069Q (48.9%), 2304-2305insC (11.4%), R616Q (5.7%), and A1003T (5.7%). The results produced in this paper indicate that the best strategy for mutation detection in Yugoslavian patients with WD is an SSCP analysis of exons 14, 8, 5, and 13, where most of the defects (73.1%) lie, followed by mutation analysis of the remaining exons in ATP7B in patients in whom the mutation was not detected by the finitial screening. These data can be used to develop straightforward genetic testing in this population or in other countries composed of a genetically mixed population like the United States, where a significant number of immigrants came from Central and Eastern Europe.

Circulating nociceptin levels during the cluster headache period

The trigeminal innervation of the dura and its vessels has a prominent role in the mechanism of cluster headache. Nociceptin, an opioid neuropeptide, is the endogenous ligand of the OP-4 receptor, with both algesic and analgesic properties depending on the site of action. Nociceptin and its receptor are expressed by trigeminal ganglion cells where they co-localize with calcitonin gene-related peptide, a marker peptide of the trigeminovascular neurones. Nociceptin inhibits neurogenic dural vasodilatation, a phenomenon related to trigeminovascular activation. To explore its possible involvement in cluster headache, we studied circulating levels of nociceptin when attack-free during the cluster period, and also after the termination of the cluster period, using radioimmunoassay. In 14 cluster headache patients nociceptin levels during the cluster period were significantly lower than in age-, and sex-matched controls (4.91 +/- 1.96 vs. 9.58 +/- 2.57 pg/ml, P < 0.01). After the termination of the cluster period nociceptin levels (8.60 +/- 1.47 pg/ml) were not statistically different from controls. Nociceptin levels did not correlate with age, length of disease or episode length. Lower nociceptin levels during the cluster period may result in a defective regulation of trigeminal activity that might not protect sufficiently against the attacks.

Correlation of ATP7B genotype with phenotype in Chinese patients with Wilson disease

AIM: To determine the mutational characterization of P-type ATP7B gene and to explore the correlation of ATP7B genotype to phenotype in Chinese patients with Wilson disease (WD).

METHODS: Seventy-five patients with WD from 72 no-kinship families, 44 males and 31 females, were enrolled in this study. The age of onset ranged from 4 to 39 years, ≤ 18 years in 72 patients. Some exons of ATP7B gene mutations were analyzed in patients with WD by using biochemical methods, polymerase chain reaction-single strand configuration polymorphism (PCR-SSCP) and DNA sequence analysis. A total of 778 coding regions were identified with restriction enzyme Msp I. The activity of Cu-ATPase was assessed by measuring inorganic phosphorus.

RESULTS: Sixty-six of 75 patients (88%) had with hepatic manifestations, 39 of them had only hepatic manifestations, 27 patients had hepatic and neurological manifestations or other symptoms at the same time (16 patients had associated neurological manifestation, 3 patients had osteopathy, 8 patients had other symptoms). Eight of the 75 patients (10.7%) had only neurological symptoms, one patient (5 years old) had no symptom. Twelve changing patterns were detected in ATP7B gene by DNA sequencing, including seven mutations (R778L, C656X, G943D, V1140A, V1106I V1216M and 1384del17), six polymorphisms (IVS4-5t/c, A2495G, C2310G, IVS18 + 6c/t and IVS20 + 5a/g). R778L occurred in 49/66 patients (74%) with hepatic manifestations, homozygosis of R778L in 16 patients, heterozygosity of R778L in 33 patients. V1106I mutation of ATP7B gene occurred in 2 patients with delaying onset of clinical symptoms. Cu-ATPase activity of three patients with known mutations (R778L/ V1106I/A2495G, R778L/V1216M and R778L/R778L) were determined, and the activity of Cu-ATPase was decreased by 44.55%, 88.23% and 69.49% respectively.

CONCLUSION: 1384del17bp is a novel mutation found in WD patients. R778L is the most common mutation of ATP7B gene. There is a correlation between R778L and hepatic manifestations in WD patient.

Ontogenic and adult whole body distribution of aminopeptidase N in rat investigated by in vitro autoradiography

Aminopeptidase N (APN), which is widely distributed in mammalian tissues, is able to cleave numerous regulatory peptides. The selective inhibitor of APN, [(125)I] RB129, has been used to study the distribution of this exopeptidase during rat prenatal development and adult life by in vitro whole-body autoradiography. In the central nervous system, APN shows a weak labeling compared to the major part of the non-nervous tissues in the embryo and in the adult. APN is progressively expressed in kidney, intestine, heart, lung, sensory organs, eye, and thymus. In organs such as the liver, the cartilages and the bones, altered levels of APN expression are observed during the development, or in the embryo compared to the adult, suggesting a role of APN during the liver haematopoiesis and bone growth. At this time, all the physiological functions of APN are still incompletely known, however its developmental pattern of expression strongly suggests a function of modulation of this enzyme during the development, next in physiological and/or pathological situations in adult. In this way, APN could represent a new therapeutic target in pathological processes, such as tumoral proliferation and/or angiogenesis associated with cancer development, where an increase in the level of this enzyme has been observed.

Review article: diagnosis and current therapy of Wilson's disease

Wilson's disease is an autosomal recessive inherited disorder of hepatic copper metabolism resulting in liver disease and/or neuropsychiatric disease. The diagnosis of neurological disease is straightforward if the following symptoms are present: Kayser-Fleischer rings, typical neurological symptoms and low serum ceruloplasmin levels. The diagnosis is more complex in patients presenting with liver diseases. None of the commonly used parameters alone allows a diagnosis with certainty. A combination of various laboratory parameters is necessary to firmly establish the diagnosis. In the future, limited mutation analysis may play an important diagnostic role. Recently, a group of international experts has proposed a score based on a variety of tests and clinical symptoms. The validity of this score needs to be assessed prospectively. Treatment requires life-long administration of copper chelators (d-penicillamine, trientine). A frequently used alternative is zinc. None of these treatments has been tested by prospective randomized controlled studies. Liver transplantation is reserved for severe or treatment-resistant cases with advanced liver disease, whilst experience with refractory neuropsychiatric disease is limited.

Rising plasma nociceptin level during development of HCC: a case report

AIM

Although liver cirrhosis is a predisposing factor for hepatocellular carcinoma (HCC), relatively few reports are available on HCC in primary biliary cirrhosis. High plasma nociceptin (N/OFQ) level has been shown in Wilson disease and in patients with acute and chronic pain.

METHODS

We report a follow-up case of HCC, which developed in a patient with primary biliary cirrhosis. The tumor appeared 18 years after the diagnosis of PBC and led to death within two years. Alfa fetoprotein and serum nociceptin levels were monitored before and during the development of HCC. Nociceptin content was also measured in the tumor tissue.

RESULTS

The importance and the curiosity of the presented case was the novel finding of the progressive elevation of plasma nociceptin level up to 17-fold (172 pg/mL) above the baseline (9.2+/-1.8 pg/mL), parallel with the elevation of alpha fetoprotein (from 13 ng/mL up to 3 480 ng/mL) during tumor development. Nociceptin content was more than 15-fold higher in the neoplastic tissue (0.16 pg/mg) than that in the tumor-free liver tissue samples (0.01 pg/mg) taken during the autopsy.

CONCLUSION

Results are in concordance with our previous observation that a very high plasma nociceptin level may be considered as an indicator for hepatocellular carcinoma.

Increased nociceptin/orphanin FQ plasma levels in hepatocellular carcinoma

AIM

The heptadecapeptide nociceptin alias orphanin FQ is the endogenous agonist of opioid receptor-like1 receptor. It is involved in modulation of pain and cognition. High blood level was reported in patients with acute and chronic pain, and in Wilson disease. An accidental observation led us to investigate nociceptin in hepatocellular carcinoma.

METHODS

Plasma nociceptin level was measured by radioimmunoassay, aprotinin was used as protease inhibitor. Hepatocellular carcinoma was diagnosed by laboratory, ultrasound, other imaging, and confirmed by fine needle biopsy. Results were compared to healthy controls and patients with other chronic liver diseases.

RESULTS

Although nociceptin levels were elevated in patients with Wilson disease (14.0+/-2.7 pg/mL, n=26), primary biliary cirrhosis (12.1+/-3.2 pg/mL, n=21) and liver cirrhosis (12.8+/-4.0 pg/mL, n=15) compared to the healthy controls (9.2+/-1.8 pg/mL, n=29, P<0.001 for each), in patients with hepatocellular carcinoma a ten-fold increase was found (105.9+/-14.4 pg/mL, n=29, P<0.0001). High plasma levels were found in each hepatocellular carcinoma patient including those with normal alpha fetoprotein and those with pain (104.9+/-14.9 pg/mL, n=12) and without (107.7+/-14.5 pg/mL, n=6).

CONCLUSION

A very high nociceptin plasma level seems to be an indicator for hepatocellular carcinoma. Further research is needed to clarify the mechanism and clinical significance of this novel finding.

Non-radioactive detection of five common microsatellite markers for ATP7B gene in Wilson disease patients

Haplotype analysis using microsatellite markers is a useful indicator of specific mutations and is often exploited as the first large-scale screening technique to carry out the molecular characterization of the disease gene in probands from a specific population. However, the methodologies available are still cumbersome and require the use of either radioactive compounds or specialized equipment suitable to follow fluorescent dyes. Both these techniques may not be available for newly developing clinical laboratories. We have set up a sensitive and easy-to-use protocol to characterize five closely spaced, highly polymorphic microsatellite polymorphisms (CA repeats) that span the Wilson disease (WD) region, i.e. D13S316, D13S133, D13S301, D13S314, D13S315. The technique described here for the analysis of the WD gene microsatellite system relies on the quick detection method of silver staining, avoiding the use of toxic or sophisticated equipment. This approach could be the method of choice to implement molecular genetic testing in clinical laboratories, even those not especially equipped for DNA analysis and in particular in newly developed molecular genetics centers in countries whose population has not yet been characterized for WD-causing ATP7B gene mutations.

Biglycan deficiency interferes with ovariectomy-induced bone loss

Biglycan is a matrix proteoglycan with a possible role in bone turnover. In a 4-week study with sham-operated or OVX biglycan-deficient or wildtype mice, we show that biglycan-deficient mice are resistant to OVX-induced trabecular bone loss and that there is a gender difference in the response to biglycan deficiency.

INTRODUCTION

Biglycan (bgn) is a small extracellular matrix proteoglycan enriched in skeletal tissues, and biglycan-deficient male mice have decreased trabecular bone mass and bone strength. The purpose of this study was to investigate the bone phenotype of the biglycan-deficient female mice and to investigate the effect of estrogen depletion by ovariectomy (OVX).

MATERIALS AND METHODS

OVX or sham operations were performed on 21-week-old mice that were divided into four groups: wt sham (n = 7), wt OVX (n = 9), bgn-deficient sham (n = 10) and bgn-deficient OVX (n = 10). The mice were killed 4 weeks after surgery. Bone mass and bone turnover were analyzed by peripheral quantitative computed tomography (pQCT), biochemical markers, and histomorphometry.

RESULTS AND CONCLUSIONS

In contrast to the male mice, there were only few effects of bgn deficiency on bone metabolism in female mice, showing a clear gender difference. However, when stressed by OVX, the female bgn knockout (KO) mice were resistant to the OVX-induced trabecular bone loss. The wt mice showed a decrease in trabecular bone mineral density by pQCT measurements, a decrease in trabecular bone volume (BV/TV), and an increase in mineral apposition rate. In contrast, no significant changes were detected in bgn KO mice after OVX. In addition, analysis of the bone resorption marker deoxypyridinoline showed no significant increase in the bgn KO OVX mice compared with bgn KO sham mice. Measurements of serum osteoprotegerin (OPG) and RANKL revealed increased levels of OPG and decreased levels of RANKL in the bgn KO mice compared with wt mice. In conclusion, the bgn deficiency protects against increased trabecular bone turnover and bone loss in response to estrogen depletion, supporting the concept that bgn has dual roles in bone, where it may modulate both formation and resorption ultimately influencing the bone turnover process.

Genetic factors in the pathogenesis of primary biliary cirrhosis

Current knowledge of the genetic basis of PBC is at best incomplete and at worst poor. Studies so far may be used as a guide to the pitfalls that await unwary investigators and also in deciding where to look and which genes or systems are most likely to yield informative results. The Human Genome Project has revealed a vast array of polymorphism that is too much to contemplate even with the best of current techniques. The crucial processes are the selection of candidates and study design. The strong genetic associations so far in PBC are with chromosomes 6p21.3 and 2q and include; HLA DRBI*08 haplotypes, CTLA4* G and IL1RN-IL1B haplotypes, CASP8, and nramp1. Many of the latter should be considered with caution until confirmed in independent series. Other associations with MBL, APOE and VDR remain to be confirmed. There are also several informative negatives, MMP3 and IL10 for example. It is unlikely that the only genes that influence disease susceptibility and progression in PBC are immunoregulatory genes concerned with T cell immunity. Recent studies indicate a new era for immunogenetics, when genes encoding all immune active proteins may be considered as candidates. One should not concentrate solely on the immune response as recent investigations of mannose binding lectin and apolipoprotein-E testify. One is only just beginning to understand the genetic basis of complex diseases like PBC. The key issues for future investigators are: defining the mechanisms where by self tolerance is broken, defining the mechanisms that determine the rate of disease progression, and identifying genetic markers to predict progression and malignancy. Assessing the genetic basis of variability in disease progression. The significant variation in rate of progression of PBC has led to the hypothesis that genes, in addition to contributing to disease susceptibility, may also determine the rate of disease progression. Several of the studies mentioned earlier have suggested associations between alleles at polymorphic loci and rate of progression . All studies performed to date, however, have been retrospective in nature. One problem inherent in such studies is that of definition of disease progression. One simple definition, that of histological progression to Scheuer stage IV disease , requires liver biopsy. The need to perform repeat biopsies raises ethical problems in cases where there is no other clinical indication. Studies of histologic progression in patients in the control arm of therapeutic trials represent one scenario where repeat biopsy would be indicated. However, the typical time course of such trials is 2 years, insufficient for meaningful assessment of disease progression and natural history, particularly in PBC where there is marked heterogeneity and, as a result, tissue sampling error. Yet, alternative systems for assessing disease progression, such as the Mayo prognostic score, lack sensitivity in any scenario other than existing advanced disease. Outlook for the future. Clinical observations support a significant genetic component to disease susceptibility. Elucidating predisposing genetic associations will markedly assist in understanding the pathophysiology of disease. Investigations to date have been restricted to various community-based case-control association studies, with well-recognized limitations. In future SNP maps and haplotype maps from the Human Genome Project will be available. Studies will require the collection of several well-characterized patients. To meet the required statistical power this will necessitate collaboration on a national and international scale. It is essential that these studies address the relationship between genes and disease progression. The possibility of identifying, in the early stages of disease, patients who are at elevated risk for more rapid progression, would have obvious clinical benefit in terms of patient management and therapy.

Preventative therapy in primary biliary cirrhosis

Because the etiology of PBC is still unknown, therapies remain empirical. Moreover, no contributions on preventative therapy supported by evidence-based medicine have been published to date. However, there are at least two groups of subjects who might benefit from preventative therapy: (1) subjects with normal liver enzymes who are found AMA-positive during autoantibody screening and (2) subjects transplanted for PBC with no histologic or biochemical signs of disease recurrence. The key questions are whether any therapy should be proposed to these subjects, since the natural history of the disease is very long, and what kind of treatment should be prescribed. UDCA is a well-tolerated, definitely "physiologic" treatment, but it is expensive and two recent meta-analyses question its benefit on survival. Current theory considers PBC an autoimmune disease, with a genetic predisposition, possibly triggered by an infectious agent or xenobiotic. If this is so, gene therapies might be the most promising future preventative therapies. For the time being, however, the only practical preventative management is in regards to the complications of PBC, namely osteopenia and portal hypertension.

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Endogenous opiates and behavior: 2002

This paper is the twenty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2002 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).

Dipeptidyl-peptidase IV from bench to bedside: an update on structural properties, functions, and clinical aspects of the enzyme DPP IV

Dipeptidyl-peptidase IV/CD26 (DPP IV) is a cell-surface protease belonging to the prolyloligopeptidase family. It selectively removes the N-terminal dipeptide from peptides with proline or alanine in the second position. Apart from its catalytic activity, it interacts with several proteins, for instance, adenosine deaminase, the HIV gp120 protein, fibronectin, collagen, the chemokine receptor CXCR4, and the tyrosine phosphatase CD45. DPP IV is expressed on a specific set of T lymphocytes, where it is up-regulated after activation. It is also expressed in a variety of tissues, primarily on endothelial and epithelial cells. A soluble form is present in plasma and other body fluids. DPP IV has been proposed as a diagnostic or prognostic marker for various tumors, hematological malignancies, immunological, inflammatory, psychoneuroendocrine disorders, and viral infections. DPP IV truncates many bioactive peptides of medical importance. It plays a role in glucose homeostasis through proteolytic inactivation of the incretins. DPP IV inhibitors improve glucose tolerance and pancreatic islet cell function in animal models of type 2 diabetes and in diabetic patients. The role of DPP IV/ CD26 within the immune system is a combination of its exopeptidase activity and its interactions with different molecules. This enables DPP IV/CD26 to serve as a co-stimulatory molecule to influence T cell activity and to modulate chemotaxis. DPP IV is also implicated in HIV-1 entry, malignant transformation, and tumor invasion.

Similar increased serum dipeptidyl peptidase IV activity in chronic hepatitis C and other viral infections

BACKGROUND

Dipeptidyl peptidase IV is a transmembrane enzyme widely expressed in many cell types, but also present as a soluble form in biological fluids. Its abnormal activity is sometimes associated with liver disease related pathologies.

OBJECTIVES

The aim of this study was to evaluate the clinical relevance of changes in serum DPPIV activity in hepatitis C and other viral infections.

STUDY DESIGN

DPPIV activity was assessed by using a microplate-based colorimetric assay on serum from 88 subjects: 12 healthy uninfected controls, 10 patients with primary biliary cirrhosis (PBC) as a reference group, 36 HCV-infected patients, and patients suffering from viral infections of different etiologies. Levels of DPPIV activity were compared with: (1) those of other serum biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma glutamyl transpeptidase (GGT), and bilirubin concentrations; and (2) criteria representative of liver histological status.

RESULTS

Compared with healthy subjects, DPPIV activity was significantly increased during viral infections and in PBC (P<0.01). In HCV-infected patients, the median activity (interquartile range, IQR), 29.78 IU/l (24.66-35.95), differed significantly (P<0.05) from that of controls: 21.42 (19.76-24.93). No correlation was observed between DPPIV activity and either ALT, AST, bilirubin, or the stage of liver fibrosis and necroinflammatory activity, although GGT was moderately correlated (r=0.58, P<0.05).

CONCLUSIONS

Although we confirmed an elevation of serum DPPIV activity in PBC, it seems to be a non-specific phenomenon common to viral infections. The absence of correlation between serum DPPIV and markers of liver disease in HCV-infected patients, suggests that this activity originates not only from the liver, but also from other sources such as peripheral blood cells involved in the control of viral infections.

Cholestatic syndromes

Further insights into the cellular and molecular mechanisms underlying hepatobiliary transport function and its regulation now permit a better understanding of the pathogenesis and treatment options of cholestatic liver diseases. Identification of the molecular basis of hereditary cholestatic syndromes will result in an improved diagnosis and management of these conditions. New insights into the pathogenesis of extrahepatic manifestations of cholestasis (eg, pruritus) have facilitated new treatment strategies. Important new studies have been published about the pathogenesis, clinical features, diagnosis, and treatment of primary biliary cirrhosis, primary sclerosing cholangitis, cholestasis of pregnancy, total parenteral nutrition-induced cholestasis, drug-induced cholestasis, and viral cholestatic syndromes.

High serum osteoprotegerin and low RANKL in primary biliary cirrhosis

BACKGROUND/AIMS

Osteoprotegerin is decoy receptor for osteoclast activating factor, RANKL, and impairs osteoclast funtion. Since osteoporosis is common in primary biliary cirrhosis (PBC), we investigated osteoprotegerin, RANKL and markers of bone turnover in PBC.

METHODS

Serum osteoprotegerin, RANKL, osteocalcin (OC) and C-terminal cross-linking telopeptide of type I collagen (CTX-I) were measured by ELISA in 41 patients with PBC, 16 women with chronic hepatitis C (CHC), and as controls in 44 age-matched healthy and 74 post-menopausal osteopenic otherwise healthy women.

RESULTS

Serum osteoprotegerin levels were higher in PBC patients (7.8+/-3.0 pmol/l) than in healthy controls (4.4+/-2.3 pmol/l) and osteopenic women (4.0+/-1.0 pmol/l, P<0.0001 for both). RANKL levels were lower in PBC (0.9+/-1.8 pmol/l, P<0.0001) than in healthy controls (1.3+/-0.5 pmol/l). In CHC both osteoprotegerin (9.7+/-4.2 pmol/l) and RANKL (3.2+/-4.7 pmol/l) were elevated compared to the control groups (P<0.0001, for both). There was a positive correlation between serum osteoprotegerin and OC, CTX-I and AST but not with bone mineral density in PBC.

CONCLUSIONS

The mechanisms and role of elevated osteoprotegerin and low RANKL in PBC are unclear, but it might partly represent a compensatory mechanism to negative balance of bone remodeling. High OPG and RANKL levels found in CHC might suggest that inflammatory process in the liver could also contribute to the elevation of osteoprotegerin.

The multifunctional or moonlighting protein CD26/DPPIV

CD26/DPPIV can be considered a moonlighting protein because it is a multifunctional protein that exerts its different functions depending on cell type and intra- or extracellular conditions in which it is expressed. In the present review, we summarize all its known functions in relation to physiological and pathophysiological conditions. The protein is a proteolytic enzyme, receptor, costimulatory protein, and is involved in adhesion and apoptosis. The CD26/DPPIV protein plays a major role in immune response. Abnormal expression is found in the case of autoimmune diseases, HIV-related diseases and cancer. Natural substrates for CD26/DPPIV are involved in immunomodulation, psycho/neuronal modulation and physiological processes in general. Therefore, targeting of CD26/ DPPIV and especially its proteolytic activity has many therapeutic potentials. On the other hand, there are homologous proteins with overlapping proteolytic activity, which thus may prevent specific modulation of CD26/DPPIV. In conclusion, CD26/DPPIV is a protein present both in various cellular compartments and extracellularly where it exerts different functions and thus is a true moonlighting protein.