Trace Element Imbalances in Acquired Hepatocerebral Degeneration and Changes after Liver Transplant

Brain manganese (Mn) accumulation is a key feature in patients with acquired hepatocerebral degeneration (AHD). The role of trace elements other than Mn in AHD needs to be clarified. In this study, using inductively coupled plasma mass spectrometry, we aimed to evaluate blood levels of trace elements in patients with AHD before and after liver transplantation (LT). Trace element levels in the AHD group were also compared with those of healthy controls (blood donors, n = 51). Fifty-one AHD patients were included in the study (mean age: 59.2 ± 10.6 years; men: 72.5%). AHD patients had higher levels of Mn, Li, B, Ni, As, Sr, Mo, Cd, Sb, Tl and Pb and a higher Cu/Se ratio, and lower levels of Se and Rb. Six patients (two women; mean age 55 ± 8.7 years) underwent LT, and there was an improvement in neurological symptoms, a significant increase in the Zn, Se and Sr levels, and a decrease in the Cu/Zn and Cu/Se ratios. In summary, several trace element imbalances were identified in AHD patients. Liver transplantation resulted in the improvement of neurological manifestations and the oxidant/inflammatory status. It is possible that observed changes in trace element levels may play a role in the pathophysiology and symptomatology of AHD.

Extramedullary Acute Leukemia-Still an Unforeseen Presentation

Myeloid sarcomas (MS) are rare extramedullary (EM) hematological tumors that generally arise during the natural course of acute myeloid leukemia (AML), occurring concomitantly with the onset of systemic leukemia; it can also occur following onset but rarely before. Common sites of EM involvement include the lymph nodes, skin, soft tissue, bone and peritoneum. Herein, we report the case of a 63-year-old man who presented EM AML upon initial diagnosis involving the bone marrow, lymph nodes and skin (leukemia cutis). A diagnosis was made based on immunohistochemistry (IHC). This case presents a diagnostic dilemma due to its atypical presentation and the sites involved. It also highlights the importance of IHC in the diagnosis of EM AML. The potential role of hypomethylating agents and Venetoclax in cases not eligible for hematopoietic stem cell transplant are also discussed.

Once- versus twice-daily dosing of eliglustat in adults with Gaucher disease type 1: The Phase 3, randomized, double-blind EDGE trial

Eliglustat is a first-line oral therapy for adults with Gaucher disease type 1 (GD1) with compatible CYP2D6-metabolizer phenotypes (>90% of patients). The randomized, double-blind EDGE trial (NCT01074944, Sanofi Genzyme) evaluated once-daily eliglustat dosing compared with the approved twice-daily regimen at the same total daily dose in adults with GD1. Subjects received twice-daily dosing during a 6- to 18-month lead-in period. Only subjects who attained prespecified treatment goals for hemoglobin, platelet count, spleen and liver volumes, and bone symptoms during the lead-in period were randomized to once- or twice-daily dosing. Of 170 enrolled patients, 156 completed the lead-in period and 131 met all requirements to enter the double-blind treatment period. To achieve the composite primary endpoint in the double-blind period, patients had to maintain clinical stability relative to baseline on all five endpoints (hemoglobin, platelet count, spleen and liver volumes, and bone symptoms) and meet pharmacokinetic and other tolerability requirements as determined by the investigator after 1year of eliglustat treatment. After 1year, 80.4% (95% CI: 67.6, 89.8) of once-daily patients were stable compared with 83.1% (95% CI: 71.0, 91.6) of twice-daily patients. The 95% CI for the mean difference of -2.7% between groups was -17.7, 11.9. Because the lower bound of the CI exceeded the pre-defined non-inferiority margin of -15%, once-daily dosing could not be declared non-inferior to twice-daily dosing. Both once-daily and twice-daily patients maintained mean values for hematologic and visceral measures within established therapeutic goals during the double-blind treatment and long-term extension periods. Eliglustat was generally well-tolerated during this long-term trial (mean treatment duration: 3.3years), with just four withdrawals (2%) for related adverse events (AE), and similar AE profiles for both dosing regimens. Patients on twice-daily eliglustat showed more stability overall, and this dose regimen was better tolerated, confirming the dosing regimen for most patients specified in the drug label.

Management and monitoring recommendations for the use of eliglustat in adults with type 1 Gaucher disease in Europe

PURPOSE

In Gaucher disease, diminished activity of the lysosomal enzyme, acid β-glucosidase, leads to accumulation of glucosylceramides and related substrates, primarily in the spleen, liver, and bone marrow. Eliglustat is an oral substrate reduction therapy approved in the European Union and the United States as a first-line treatment for adults with type 1 Gaucher disease who have compatible CYP2D6 metabolism phenotypes. A European Advisory Council of experts in Gaucher disease describes the characteristics of eliglustat that are distinct from enzyme augmentation therapy (the standard of care) and miglustat (the other approved substrate reduction therapy) and recommends investigations and monitoring for patients on eliglustat therapy within the context of current recommendations for Gaucher disease management.

RESULTS

Eliglustat is a selective, potent inhibitor of glucosylceramide synthase, the enzyme responsible for biosynthesis of glucosylceramides which accumulate in Gaucher disease. Extensive metabolism of eliglustat by CYP2D6, and, to a lesser extent, CYP3A of the cytochrome P450 pathway, necessitates careful consideration of the patient's CYP2D6 metaboliser status and use of concomitant medications which share metabolism by these pathways. Guidance on specific assessments and monitoring required for eliglustat therapy, including an algorithm to determine eligibility for eliglustat, are provided.

CONCLUSIONS

As a first-line therapy for type 1 Gaucher disease, eliglustat offers eligible patients a daily oral therapy alternative to biweekly infusions of enzyme therapy. Physicians will need to carefully assess individual Gaucher patients to determine their appropriateness for eliglustat therapy. The therapeutic response to eliglustat and use of concomitant medications will require long-term monitoring.

Management goals for type 1 Gaucher disease: An expert consensus document from the European working group on Gaucher disease

Gaucher Disease type 1 (GD1) is a lysosomal disorder that affects many systems. Therapy improves the principal manifestations of the condition and, as a consequence, many patients show a modified phenotype which reflects manifestations of their disease that are refractory to treatment. More generally, it is increasingly recognised that information as to how a patient feels and functions [obtained by patient- reported outcome measurements (PROMs)] is critical to any comprehensive evaluation of treatment. A new set of management goals for GD1 in which both trends are reflected is needed. To this end, a modified Delphi procedure among 25 experts was performed. Based on a literature review and with input from patients, 65 potential goals were formulated as statements. Consensus was considered to be reached when ≥75% of the participants agreed to include that specific statement in the management goals. There was agreement on 42 statements. In addition to the traditional goals concerning haematological, visceral and bone manifestations, improvement in quality of life, fatigue and social participation, as well as early detection of long-term complications or associated diseases were included. When applying this set of goals in medical practice, the clinical status of the individual patient should be taken into account.

Carriers of the Complex Allele HFE c.[187C>G;340+4T>C] Have Increased Risk of Iron Overload in São Miguel Island Population (Azores, Portugal)

Iron overload is associated with acquired and genetic conditions, the most common being hereditary hemochromatosis (HH) type-I, caused by HFE mutations. Here, we conducted a hospital-based case-control study of 41 patients from the São Miguel Island (Azores, Portugal), six belonging to a family with HH type-I pseudodominant inheritance, and 35 unrelated individuals fulfilling the biochemical criteria of iron overload compatible with HH type-I. For this purpose, we analyzed the most common HFE mutations– c.845G>A [p.Cys282Tyr], c.187C>G [p.His63Asp], and c.193A>T [p.Ser65Cys]. Results revealed that the family’s HH pseudodominant pattern is due to consanguineous marriage of HFE-c.845G>A carriers, and to marriage with a genetically unrelated spouse that is a -c.187G carrier. Regarding unrelated patients, six were homozygous for c.845A, and three were c.845A/c.187G compound heterozygous. We then performed sequencing of HFE exons 2, 4, 5 and their intron-flanking regions. No other mutations were observed, but we identified the -c.340+4C [IVS2+4C] splice variant in 26 (74.3%) patients. Functionally, the c.340+4C may generate alternative splicing by HFE exon 2 skipping and consequently, a protein missing the α1-domain essential for HFE/ transferrin receptor-1 interactions. Finally, we investigated HFE mutations configuration with iron overload by determining haplotypes and genotypic profiles. Results evidenced that carriers of HFE-c.187G allele also carry -c.340+4C, suggesting in-cis configuration. This data is corroborated by the association analysis where carriers of the complex allele HFE-c.[187C>G;340+4T>C] have an increased iron overload risk (RR = 2.08, 95% CI = 1.40−2.94, p<0.001). Therefore, homozygous for this complex allele are at risk of having iron overload because they will produce two altered proteins—the p.63Asp [c.187G], and the protein lacking 88 amino acids encoded by exon 2. In summary, we provide evidence that the complex allele HFE-c.[187C>G;340+4T>C] has a role, as genetic predisposition factor, on iron overload in the São Miguel population. Independent replication studies in other populations are needed to confirm this association.

Genetic basis of congenital erythrocytosis: mutation update and online databases

Congenital erythrocytosis (CE), or congenital polycythemia, represents a rare and heterogeneous clinical entity. It is caused by deregulated red blood cell production where erythrocyte overproduction results in elevated hemoglobin and hematocrit levels. Primary congenital familial erythrocytosis is associated with low erythropoietin (Epo) levels and results from mutations in the Epo receptor gene (EPOR). Secondary CE arises from conditions causing tissue hypoxia and results in increased Epo production. These include hemoglobin variants with increased affinity for oxygen (HBB, HBA mutations), decreased production of 2,3-bisphosphoglycerate due to BPGM mutations, or mutations in the genes involved in the hypoxia sensing pathway (VHL, EPAS1, and EGLN1). Depending on the affected gene, CE can be inherited either in an autosomal dominant or recessive mode, with sporadic cases arising de novo. Despite recent important discoveries in the molecular pathogenesis of CE, the molecular causes remain to be identified in about 70% of the patients. With the objective of collecting all the published and unpublished cases of CE the COST action MPN&MPNr-Euronet developed a comprehensive Internet-based database focusing on the registration of clinical history, hematological, biochemical, and molecular data (http://www.erythrocytosis.org/). In addition, unreported mutations are also curated in the corresponding Leiden Open Variation Database.

Molecular study of congenital erythrocytosis in 70 unrelated patients revealed a potential causal mutation in less than half of the cases (Where is/are the missing gene(s)?)

INTRODUCTION

Congenital erythrocytosis can be classified as primary, when the defect is intrinsic to the RBC progenitors and independent of the serum erythropoietin (Epo) concentration, or secondary, when the erythrocytosis is the result of an upregulation of Epo production. Primary erythrocytosis is associated with mutations in the EPOR gene, secondary CE can de due to mutations that stabilize the hemoglobin in the oxygenated form or to mutations in the genes that control the transcriptional activation of the EPO gene - VHL, EGLN1, EPAS1. Chuvash polycythemia, caused by mutations in VHL gene, shares features of both primary and secondary erythrocytosis, with increased Epo production but also hypersensitivity of progenitors to Epo.

MATERIAL AND METHODS

With the main objective of describing the etiology and molecular basis of CE, we have studied 70 consecutive unrelated patients presenting with idiopathic erythrocytosis from our hematology clinic or referred from other centers. According to a study algorithm, we have sequenced all the genes described as associated with CE.

RESULTS AND DISCUSSION

Erythrocytosis molecular etiology was identify in 25 (36%) of the 70 subjects. High-affinity Hb variants were the most common cause, present in 20% of the cases. New mutations were identified in the JAK2, EPOR, VHL, and EGLN1 genes.

CONCLUSIONS

High-affinity hemoglobin variants are a very rare cause of secondary CE, but it seems likely that their incidence may be underestimated. Our experience shows that in erythrocytosis with a dominant inheritance and normal or inappropriate high Epo levels, the HBB and HBA genes should be the first to be studied. In spite of the seven genes known to be involved in CE, the majority of the cases have unknown etiology.

A phase I trial of vorinostat in children with refractory solid tumors: A Children's Oncology Group Study

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Background: Vorinostat, an orally administered histone deacetylase inhibitor, has potent antitumor activity against human cell lines in vitro (IC50 0.5 to 5 μM) and in xenograft models. A phase I trial of vorinostat was conducted in children with recurrent or refractory solid tumors to determine the maximum tolerated dose (MTD), dose limiting toxicity (DLT), pharmacokinetics (PK) of vorinostat, and to assess accumulation of histone acetylation in peripheral blood mononuclear cells (PBMCs). Methods: Vorinostat was administered once daily at dose levels of 180, 230, and 300 mg/m2/d. Courses were 28 days in duration, without interruption. PK analysis was performed during the 1st course. Vorinostat's ability to induce acetyl-histone (H3) accumulation in vivo was studied by western blot analysis. Results: 30 patients, 17 males, median age 15 years (range 4–21), were enrolled; 24 patients were fully evaluable for toxicity. At 180 mg/m2/d, 1/6 pts developed DLT (deep vein thrombosis) and at 230 mg/m2/d 1/6 pts developed DLT (hypokalemia). At 300 mg/m2/d, DLTs consisted of reversible hypokalemia (n=1), neutropenia (n=1) and thrombocytopenia (n=2), defining the MTD as 230 mg/m2/d. Other non-dose limiting grade 3 or 4 toxicities included elevated ALT/AST, hyperbilirubinemia, leucopenia, and lymphopenia. Western blot analysis of PBMC protein isolates found clear evidence of dose- dependent accumulation of acetylated H3 histones. 1 patient with a spindle cell sarcoma received 8 courses and 1 patient with a low-grade astrocytoma had an unconfirmed minor response. Conclusions: Vorinostat is well tolerated in children with recurrent or refractory solid tumors and inhibits histone deacetylase activity in PBMC. The recommended phase II dose for children with solid tumors is 230 mg/m2/d.

No significant financial relationships to disclose.

Vitamin D receptor ontogenesis in rat liver

Vitamin D through its receptor (VDR) plays a major role in bone mineral metabolism. However, VDR is also present in a variety of cell lines as well as in numerous tissues, suggesting other functions of the hormone beyond bone metabolism and mineral homeostasis. At the liver level, it has been shown that vitamin D induces numerous changes (i.e. enzyme activity level, stimulation of some metabolic pathways and stimulation of the normal liver recovery after partial hepatectomy). However, some works did not find VDR in the liver, and also used liver tissue as a negative control of VDR gene expression. In this paper, we examined fetal, neonatal and adult rat tissues for the presence of VDR using a sensitive RT-PCR technique and immunohistochemistry. We found VDR mRNA and VDR protein in rat liver at all different periods of rat life. Thus, we suggest that some of the actions of vitamin D on liver could be mediated at the genomic level through the VDR, and that the use of this tissue as a negative control of VDR gene expression is clearly inappropriate.

Characterization of novel cathepsin K mutations in the pro and mature polypeptide regions causing pycnodysostosis

Cathepsin K, a lysosomal cysteine protease critical for bone remodeling by osteoclasts, was recently identified as the deficient enzyme causing pycnodysostosis, an autosomal recessive osteosclerotic skeletal dysplasia. To investigate the nature of molecular lesions causing this disease, mutations in the cathepsin K gene from eight families were determined, identifying seven novel mutations (K52X, G79E, Q190X, Y212C, A277E, A277V, and R312G). Expression of the first pro region missense mutation in a cysteine protease, G79E, in Pichia pastoris resulted in an unstable precursor protein, consistent with misfolding of the proenzyme. Expression of five mature region missense defects revealed that G146R, A277E, A277V, and R312G precursors were unstable, and no mature proteins or protease activity were detected. The Y212C precursor was activated to its mature form in a manner similar to that of the wild-type cathepsin K. The mature Y212C enzyme retained its dipeptide substrate specificity and gelatinolytic activity, but it had markedly decreased activity toward type I collagen and a cathepsin K-specific tripeptide substrate, indicating that it was unable to bind collagen triple helix. These studies demonstrated the molecular heterogeneity of mutations causing pycnodysostosis, indicated that pro region conformation directs proper folding of the proenzyme, and suggested that the cathepsin K active site contains a critical collagen-binding domain.

Regional changes in capillary supply in skeletal muscle of high-intensity endurance-trained rats

The objective of this study was to test the hypothesis that an endurance training program designed to produce recruitment of all extensor muscle fiber types during each exercise bout would stimulate capillary angiogenesis throughout rat gastrocnemius and soleus muscles. Male Sprague-Dawley rats were exercise trained 5 days/wk for 12-14 wk with exercise bouts consisting of a combination of high intensity (32 m/min on a 15% incline) and long duration (90 min/day). On completion of high-intensity endurance training (HIET) or cage activity [sedentary (Sed)], rat hindquarters were vascularly isolated and perfusion fixed with a modified Karnovsky's fixative. Capillary supply was measured in soleus and gastrocnemius muscles by using Olympus Cue 2 image-analyzer software. Capillary supply was reflected in measurements of capillary-to-fiber ratio, capillary numerical density, capillary surface area density, and capillary volume density on transversely cut tissue sections. HIET increased citrate synthase activity by 20 and 42% in the medial and long heads of the triceps brachii, respectively. Sarcomere lengths were similar in gastrocnemius and soleus muscles of Sed and HIET rats after fixation. All four indexes of capillary supply were significantly greater throughout the gastrocnemius muscle of HIET rats compared with Sed values. The relative increase in capillarity was greater in white than in red gastrocnemius muscle of HIET rats. HIET also increased capillary supply of soleus muscle. However, only capillary numerical density was statistically greater (19%) in HIET soleus compared with Sed. These results support the hypothesis that this training program would produce an increase in capillary supply in all extensor muscles.

Effect of multiple-dose activated charcoal on the clearance of high-dose intravenous aspirin in a porcine model

STUDY OBJECTIVE

To study the effect of multiple-dose activated charcoal (MDAC) on salicylate clearance in pigs given high-dose i.v. aspirin.

DESIGN

In a crossover design, six fasted pigs received 300 mg/kg i.v. aspirin followed by no treatment or MDAC (1 g/kg hourly for 6 doses by gastrostomy). Serum salicylate samples were obtained every 30 minutes for 6 hours.

RESULTS

The mean peak salicylate concentrations were 47.4 +/- 6.2 mg/dL and 48.4 +/- 3.9 mg/dL (P = .74), and the areas under the time-serum salicylate concentration curve over 6 hours were 171,000 +/- 24,000 mg.minute/L and 188,000 +/- 18,000 mg.minute/L for the control and treatment arms, respectively (P = .22). This study had a 90% power to detect a 30% difference between arms.

CONCLUSION

MDAC does not enhance the clearance of salicylate after administration of high-dose i.v. aspirin.

Prooxidant and antioxidant hepatic factors in rats chronically fed an ethanol regimen and treated with an acute dose of lindane

While acute lindane treatment and chronic ethanol feeding to rats have been associated with hepatic oxidative stress, the possible roles of these stresses in the pathogenesis of hepatic lesions reported in acute lindane intoxication and in those observed in some models of chronic alcoholism have not been established. Our previous studies in rats chronically fed ethanol regimens and then treated with a single intraperitoneal (i.p.) dose of lindane (20 mg/kg) showed that while lindane per se was invariably associated with hepatic oxidative stress, chronic ethanol feeding only produced this stress when the dietary level of vitamin E was relatively low. Chronic ethanol pretreatment did not significantly affect the lindane-associated oxidative stress, and neither chronic ethanol feeding nor acute lindane, single or in combination, produced any histologic and biochemical evidence of liver damage. In the present experiment, the acute dose of lindane was increased to 40 mg/kg, and we have studied a larger number of prooxidant and antioxidant hepatic factors. Male Wistar rats (115.5 +/- 5.4 g) were fed ad lib for 11 weeks a calorically well-balanced and nutritionally adequate basal diet, or the same basal diet plus a 32% ethanol/25% sucrose solution, also ad lib, and were then injected i.p. with a single dose of lindane or with equivalent amounts of corn oil. The results indicated that acute lindane treatment to naive rats increased practically all the prooxidant hepatic factors examined (cytochromes P450 and b5, NADPH cytochrome c reductase, NADPH oxidase), as well as the generation of microsomal superoxide radical and thiobarbituric acid reactive substances of liver homogenates, but did not modify any of the antioxidant hepatic factors studied. Conversely, the chronic administration of ethanol alone did not significantly affect the prooxidant hepatic factors but reduced some of the antioxidants (i.e., the activities of GSH-Px and the contents of alpha-tocopherol and ubiquinols 9 and 10). Although chronic ethanol pretreatment further increased the superoxide generation induced by lindane per se, it did not increase but generally reduced the effects of lindane per se on the other prooxidant factors studied. Furthermore, although acute lindane administration to ethanol-pretreated rats was associated with decreases in GSH and catalase (not affected by ethanol or lindane treatment alone), it did not substantially modify the reducing effects of ethanol feeding per se on GSH-Px, alpha-tocopherol, and ubiquinols. Once again, neither chronic ethanol feeding nor lindane treatment, single or in combination, was associated with any evidence of liver damage.

Reasons for the variability in growth hormone (GH) responses to GHRH challenge: the endogenous hypothalamic-somatotroph rhythm (HSR)

The aims of this study were: (1) to test the possibility that pre-GHRH plasma GH values could reflect the functional status of the hypothalamic-somatotroph rhythm (HSR) at testing, and thus explain if it is responsible for the marked variability in GH responsiveness to GHRH challenge and (2) to see if exogenous somatostatin (SS) could disrupt this endogenous HSR and thus make the GH responses homogeneous. (1) Two to 14 GHRH acute tests (GRF-29, 1 micrograms/kg, i.v. bolus) were performed in 12 normal men and 10 normal women at the same time (0830 h) at random intervals (2 to 60 days). Blood samples to measure plasma GH were drawn at 15 min intervals before and after GHRH challenge. Given that the increments in pre-GHRH plasma GH values (I = value at 0 min minus value at -15 min) were highly correlated with either GHRH-elicited peaks of GH (men, r = 0.81; women; r = 0.69; P less than 0.0001) or the rise in GH after the challenge (r = 0.685; P less than 0.0001, in the total of tests performed), three theoretical HSR phases were proposed: (A) I greater than or equal to 0.4 microgram/l Secretory Phase; (B) I less than or equal to 0, (from GH at -15 min greater than or equal to 1.5 microgram/l), Secretion Plateau; (C) I less than or equal to 0, (from GH at -15 min less than or equal to 1.5 microgram/l), Refractory Phase. Individually, 91% of the men and 86% of the women showed a constant HSR phase when tested at the same time of day independently of the intervals between tests. GH responses (peaks, mean +/- SEM, g/l) in Phase A (women, 51.5 +/- 4.1; men, 31.4 +/- 3.2) were significantly higher (P less than 0.01) than those in Phase B (women, 22.6 +/- 1.8; men, 19.7 +/- 1.5), and these than those in Phase C (women, 9.2 +/- 1.5; men, 6.2 +/- 0.5). The great dispersion observed when GH peaks were analysed as a whole disappeared (except in Phase A in women) when they were evaluated according to the HSR Phase at testing. (2) In seven men and eight women 7 min after stopping an infusion of SS (250 micrograms/h for 3 h) a new GHRH test was performed. Plasma GH variations prior to SS infusion expressed the previous HSR Phase, while the GHRH-elicited peak of GH established the Phase at the moment of testing.(ABSTRACT TRUNCATED AT 400 WORDS)

Growth hormone (GH) responsiveness to GHRH in normal adults is not affected by short-term gonadal blockade

The effects of changes in circulating gonadal steroids on GH secretion elicited by GHRH challenge (1 microgram/kg) in normal adults volunteers (aged 18-24 years), were evaluated in 10 women and 10 men before and after gonadal blockade was achieved by a GnRH agonist (1500 micrograms/day by nasal spray for 40 days). To see if the effect of testosterone on GH secretion was dependent on its aromatization to estradiol (E2), GHRH tests were performed in 7 normal men prior to administration of testosterone enanthate (250 mg im), 8 days after this treatment had began, and again after E2 receptor blockade with tamoxifen (30 mg for 2 days plus 10 mg on the third day 2 h before the GHRH test, po) administered 8 days after testosterone enanthate. The study of the functional status of the somatotropes at the time of GHRH testing was made according to our previous postulate. Short-term gonadal blockade did not affect the parameters of GH response to GHRH in neither women nor men. Thus, the functional blockade of the gonads may be advisable as an adjunct therapy in the treatment of hypothalamic GH-deficiency during the peripubertal stage. In the other group of men, administration of testosterone enanthate significantly increased GHRH-elicited GH release, but this was reverted after E2 receptor blockade. Since the hypothalamic-somatotrope rhythm was altered by both these pharmacological manipulations, it appears that testosterone acts on GH release mainly at the suprapituitary level, and that this action is secondary to its aromatization to E2.