Altered Peptidase Activities in Thyroid Neoplasia and Hyperplasia

Background. Papillary thyroid carcinoma (PTC), follicular thyroid adenoma (FTA), and thyroid nodular hyperplasia (TNH) are the most frequent diseases of the thyroid gland. Previous studies described the involvement of dipeptidyl-peptidase IV (DPPIV/CD26) in the development of thyroid neoplasia and proposed it as an additional tool in the diagnosis/prognosis of these diseases. However, very little is known about the involvement of other peptidases in neoplastic and hyperplastic processes of this gland. Methods. The catalytic activity of 10 peptidases in a series of 30 PTC, 10 FTA, and 14 TNH was measured fluorimetrically in tumour and nontumour adjacent tissues. Results. The activity of DPPIV/CD26 was markedly higher in PTC than in FTA, TNH, and nontumour tissues. Aspartyl aminopeptidase (AspAP), alanyl aminopeptidase (AlaAP), prolyl endopeptidase, pyroglutamyl peptidase I, and aminopeptidase B activities were significantly increased in thyroid neoplasms when compared to nontumour tissues. AspAP and AlaAP activities were also significantly higher in PTC than in FTA and TNH. Conclusions. These data suggest the involvement of DPPIV/CD26 and some cytosolic peptidases in the neoplastic development of PTC and FTA. Further studies will help to define the possible clinical usefulness of AlaAP and AspAP in the diagnosis/prognosis of thyroid neoplasms.     

Arachidyl amido cholanoic acid improves liver glucose and lipid homeostasis in nonalcoholic steatohepatitis via AMPK and mTOR regulation

BACKGROUND Arachidyl amido cholanoic acid(Aramchol) is a potent downregulator of hepatic stearoyl-CoA desaturase 1(SCD1) protein expression that reduces liver triglycerides and fibrosis in animal models of steatohepatitis. In a phase IIb clinical trial in patients with nonalcoholic steatohepatitis(NASH), 52 wk of treatment with Aramchol reduced blood levels of glycated hemoglobin A1c, an indicator of glycemic control.AIM To assess lipid and glucose metabolism in mouse hepatocytes and in a NASH mouse model [induced with a 0.1% methionine and choline deficient diet(0.1 MCD)] after treatment with Aramchol.METHODS Isolated primary mouse hepatocytes were incubated with 20 μmol/L Aramchol or vehicle for 48 h. Subsequently, analyses were performed including Western blot, proteomics by mass spectrometry, and fluxomic analysis with ~(13)C-uniformly labeled glucose. For the in vivo part of the study, male C57 BL/6 J mice were randomly fed a control or 0.1 MCD for 4 wk and received 1 or 5 mg/kg/d Aramchol or vehicle by intragastric gavage for the last 2 wk. Liver metabolomics were assessed using ultra-high-performance liquid chromatography-time of flight-MS for the determination of glucose metabolism-related metabolites.RESULTS Combination of proteomics and Western blot analyses showed increased AMPK activity while the activity of nutrient sensor mTORC1 was decreased by Aramchol in hepatocytes. This translated into changes in the content of their downstream targets including proteins involved in fatty acid(FA) synthesis and oxidation [PACCα/β(S79), SCD1, CPT1A/B, HADHA, and HADHB], oxidative phosphorylation(NDUFA9, NDUFB11, NDUFS1, NDUFV1, ETFDH, and UQCRC2), tricarboxylic acid(TCA) cycle(MDH2, SUCLA2, and SUCLG2), and ribosome(P-p70S6K[T389] and P-S6[S235/S236]). Flux experiments with ~(13)C uniformely labeled glucose showed that TCA cycle cataplerosis was reduced by Aramchol in hepatocytes, as indicated by the increase in the number of rounds that malate remained in the TCA cycle. Finally, liver metabolomic analysis showed that glucose homeostasis was improved by Aramchol in 0.1 MCD fed mice in a dose-dependent manner, showing normalization of glucose, G6P, F6P, UDP-glucose, and Rbl5 P/Xyl5 P.CONCLUSION Aramchol exerts its effect on glucose and lipid metabolism in NASH through activation of AMPK and inhibition of mTORC1, which in turn activate FA β-oxidation and oxidative phosphorylation.     

Pulmonary hypertension in systemic lupus erythematosus: prevalence,predictors and diagnostic strategy

ObjectivesTo investigate the prevalence and predictors of pulmonary hypertension (PH) in patients with systemic lupus erythematosus (SLE) and to validate a diagnostic strategy.Methods245 patients with SLE entered a screening program. Possible PH was defined as two consecutive systolic pulmonary arterial pressure (PAP) values ≥ 40 mm Hg by echocardiography. The subsequent diagnostic procedure, including right heart catheterization if needed, confirmed or excluded the diagnosis of PH secondary to cardiopulmonary disease or SLE-related pulmonary arterial hypertension (PAH). Independent predictors of PH were identified by multivariant multiple linear or logistic regression models. The sensitivity (S), specificity (SP), positive (PPV) and negative predictive values (NPV) were calculated for different screening cutoff values.Results88% patients were women. The mean (SD) age at the time of enrolment was 45 (16) years. 12 cases of PH were detected, all secondary, with a resulting prevalence of 5%. Two consecutive echocardiographic PAP measurements ≥ 40 mm Hg performed best as the cutoff point for screening (S 100%, SP 97%, PPV 70, NPV 100), as compared with single PAP measurements ≥ 30 mm Hg or ≥ 40 mm Hg The age at the time of enrolment was the only variable independently associated with PAP values (p = 0.0001), with the SLICC damage index score showing a borderline association (p = 0.08). Only the age at the time of enrolment showed an independent association with PH (OR 1.10, 95% CI 1.06–1.17).ConclusionWe found a low prevalence of PH. Screening echocardiograms in asymptomatic lupus patients are thus not recommended. Two consecutive PAP values ≥ 40 mm Hg by echocardiogram is the best screening cutoff for starting investigations in SLE patients with suspected PH.     

Genetic 3′UTR variation is associated with human pigmentation characteristics and sensitivity to sunlight

Sunlight exposure induces signalling pathways leading to the activation of melanin synthesis and tanning response. MicroRNAs (miRNAs) can regulate the expression of genes involved in pigmentation pathways by binding to the complementary sequence in their 3′untranslated regions (3′UTRs). Therefore, 3′UTR SNPs are predicted to modify the ability of miRNAs to target genes, resulting in differential gene expression. In this study, we investigated the role in pigmentation and sun‐sensitivity traits, as well as in melanoma susceptibility, of 38 different 3′UTR SNPs from 38 pigmentation‐related genes. A total of 869 individuals of Spanish origin (526 melanoma cases and 343 controls) were analysed. The association of genotypic data with pigmentation traits was analysed via logistic regression. Web‐based tools for predicting the effect of genetic variants in microRNA‐binding sites in 3′UTR gene regions were also used. Seven 3′UTR SNPs showed a potential implication in melanoma risk phenotypes. This association is especially noticeable for two of them, rs2325813 in the MLPH gene and rs752107 in the WNT3A gene. These two SNPs were predicted to disrupt a miRNA‐binding site and to impact on miRNA‐mRNA interaction. To our knowledge, this is the first time that these two 3′UTR SNPs have been associated with sun‐sensitivity traits. We state the potential implication of these SNPs in human pigmentation and sensitivity to sunlight, possibly as a result of changes in the level of gene expression through the disruption of putative miRNA‐binding sites.     

Synthesis and Characterization of Epoxidized Styrene‐Butadiene Block Copolymers as Templates for Nanostructured Thermosets

Summary: A wide range of epoxidized styrene‐block‐butadiene block copolymers were synthesized using hydrogen peroxide in the presence of an in situ prepared methyltrioctylammoniumtetrakis(diperoxotungstate)phosphate as the catalyst system in a water/dichloroethane biphasic system. ¹H NMR and FT‐IR spectra revealed that the epoxidation procedure led mainly to 1,4‐epoxidized butadiene units. GPC analysis showed that epoxidation changed the copolymer architecture into stars with fewer arms. The copolymers showed two glass transition temperatures in accordance with the phase separation for block copolymers and, as revealed in AFM images, the self‐assembly takes place on a nanometer scale. Moreover, epoxidized styrene‐butadiene (SB) copolymers showed improved miscibility with epoxy monomers leading to self‐assembled nanostructures in the uncured state. This allows them to be used as templates for nanostructured resins.

TM‐AFM phase images for: a) 40 mol‐% epoxidized copolymer (scale bar = 300 nm); b) uncured blend containing 50 wt.‐% DGEBA in 50 mol‐% epoxidized copolymer (scale bar = 1 μm), after annealing at 80 °C in vacuum for 3 h.     

Optimization of the Tet-on system to regulate interleukin 12 expression in the liver for the treatment of hepatic tumors

Interleukin 12 (IL-12) is a potent antitumoral cytokine, but it can be toxic at high doses. Therapy of liver tumors might benefit from the use of vectors enabling tight control of IL-12 expression in hepatic tissue for long periods of time. To this aim, we have improved the Tet-on system by modifying the minimal region of the inducible promoter and adjusting the level of the trans-activator using liver-specific promoters with graded activities. The resulting vectors allowed hepato-specific gene regulation with lower basal activity and higher inducibility compared with the original system in the absence of repressor molecules. The basal and final protein levels depend on the strength of the promoter that directs the transcripcional activator as well as the relative orientation of the two genes in the same plasmid. We have selected the construct combining minimal leakage with higher level of induced gene expression to regulate IL-12 after DNA transfer to mouse liver. Administration of doxycycline (Dox) enhanced IL-12 expression in a dose-dependent manner, whereas it was undetectable in serum in the noninduced state. Gene activation could be repeated several times, and sustained levels of IL-12 were achieved by daily administration of Dox. The antitumor effect of IL-12 was evaluated in a mouse model of metastatic colon cancer to the liver. Complete eradication of liver metastasis and prolonged survival was observed in all mice receiving Dox for 10 days. These data demonstrate the potential of a naked DNA gene therapy strategy to achieve tight control of IL-12 within the liver for the treatment of cancer.     

Efficacy of a self-management education programme on patients with type 2 diabetes in primary care: A randomised controlled trial

Aim

The purpose of this study was to assess the efficacy of the Spanish Diabetes Self-Management Program (SDSMP) versus usual care in adults with type 2 diabetes mellitus (T2DM) residing in a Spanish region.

Genes involved in the WNT and vesicular trafficking pathways are associated with melanoma predisposition

Multifactorial predisposition to melanoma includes genes involved in pigmentation, immunity and DNA repair. Nonetheless, missing heritability in melanoma is still important. We studied the role of 335 candidate SNPs in melanoma susceptibility by using a dedicated chip and investigating 110 genes involved in different pathways. A discovery set was comprised of 1069 melanoma patients and 925 controls from France. Data were replicated using validation phases II (1085 cases and 801 controls from Spain) and III (1808 cases and 1894 controls from Germany and a second set of Spanish samples). In addition, an exome sequencing study was performed in three high‐risk French melanoma families. Nineteen SNPs in 17 genes were initially associated with melanoma in the French population. Six SNPs were replicated in phase II, including two new SNPs in the WNT3 (rs199524) and VPS41 (rs11773094) genes. The role of VPS41 and WNT3 was confirmed in a meta‐analysis (3940 melanoma cases and 3620 controls) with two‐side p values of 0.002, (OR = 0.86) and 4.07 × 10^?10 (OR = 0.80), respectively. Exome sequencing revealed a non‐synonymous VPS41 variant in one family that was shown to be strongly associated with familial melanoma (OR = 4.46, p = 0.001) in an independent sample of 178 melanoma families. WNT3 belongs to WNT pathway known to play a crucial role in melanoma, whereas VPS41 regulates vesicular trafficking and is thought to play a role in pigmentation. Our work identified two new pathways involved in melanoma predisposition. These results may be useful in the future for identifying individuals highly predisposed to melanoma.