Search

OBJECTIVE: To determine the role of enterokine FGF15/19 in adipose tissue thermogenic adaptations. METHODS: Circulating FGF19 and gene expression (qRT-PCR) levels were assessed in subcutaneous adipose tissue from obese human patients. Effects of experimentally increased FGF15 and FGF19 levels in vivo were determined in mice using adenoviral and adeno-associated vectors. Adipose tissues were characterized in FGF15-null mice under distinct cold-related thermogenic challenges. The analyses spanned metabolic profiling, tissue characterization, histology, gene expression, and immunoblot assays. RESULTS: In humans, FGF19 levels are directly associated with UCP1 gene expression in subcutaneous adipose tissue. Experimental increases in FGF15 or FGF19 induced white fat browning in mice as demonstrated by the appearance of multilocular beige cells and markers indicative of a beige phenotype, including increased UCP1 protein levels. Mice lacking FGF15 showed markedly impaired white adipose tissue browning and a mild reduction in parameters indicative of BAT activity in response to cold-induced environmental thermogenic challenges. This was concomitant with signs of altered systemic metabolism, such as reduced glucose tolerance and impaired cold-induced insulin sensitization. CONCLUSIONS: Enterokine FGF15/19 is a key factor required for adipose tissue plasticity in response to thermogenic adaptations.

C-reactive protein (CRP) is a biomarker of systemic inflammation that has been linked to accelerated decline in walking speed in older adults. The aim of the present study was to compare the CRP levels of PD patients with vs patients without freezing of gait (FOG). Patients and controls participating in the COPPADIS-2015 study that performed blood extraction for determining molecular serum biomarkers were included. Patients with FOG were identified as those with a score of 1 or greater on item-3 of the Freezing of Gait Questionnaire (FOG-Q). Immunoassay was used for determining ultrasensitive CRP (US-CRP) level (mg/dL). In the PD group (n = 225; 61.8 +/- 9.5 years old, 61.8% males), 32% of the patients presented FOG but none in the control group (n = 65; 60.3 +/- 6.1 years old, 56.9% males) (p < 0.0001). Differences in US-CRP level were significant in patients with FOG vs patients without FOG and vs controls (0.31 +/- 0.52 vs 0.16 +/- 0.21 vs 0.21 +/- 0.22; p = 0.04). Significant differences were also observed between patients with vs without FOG (p = 0.001) but not between patients and controls (p = 0.163). US-CRP level was related to FOG (OR = 4.369; 95% CI 1.105-17.275; p = 0.036) along with H&Y (OR = 2.974; 95% CI 1.113-7.943; p = 0.030) and non-motor symptoms burden (NMSS total score; OR = 1.017; 95% CI 1.005-1.029; p = 0.006) after adjusting for age, gender, disease duration, equivalent daily levodopa dose, number of non-antiparkinsonian drugs per day, motor fluctuations, cognition, motor phenotype, and chronic use of anti-inflammatory drugs. The present study suggests that serum US-CRP level is related to FOG in PD patients. Inflammation could be linked to FOG development.

Albuquerque's community-based housing and support services demonstration program is a prospective, randomized comparison of the efficacy of three intervention strategies for treating homeless persons with alcohol-related problems. The present paper defines the target population, describes the theoretical model underlying the intervention design, and provides descriptions of the interventions, which include the social model detoxification program established for the project and the extended intervention programs undergoing evaluation. The paper then identifies some of the unanticipated developments encountered in the early phases of the program and programmatic responses to these challenges. Lessons learned during this process are described, in hopes that they might prove useful to others striving to develop similar programs.

Methionine adenosyltransferase (MAT) is an essential enzyme because it catalyzes the formation of S-adenosylmethionine, the main methyl donor. Two MAT-encoding genes (MAT1A, MAT2A) are found in mammals. The latter is expressed in proliferating liver, dedifferentiation and cancer, whereas MAT1A is expressed in adult quiescent hepatocytes. Here, we report studies on the molecular mechanisms controlling the induction of MAT2A in regenerating rat liver and in proliferating hepatocytes. The MAT2A is up-regulated at two discrete moments during liver regeneration, as confirmed by RNApol-ChIP analysis. The first one coincides with hepatocyte priming (i.e. G0-G1 transition), while the second one takes place at the G1-S interface. Electrophoretic mobility shift assays showed that a putative E2F sequence present in MAT2A promoter binds this factor and ChIP assays confirmed that E2F1, E2F3 and E2F4, as well as the pocket protein p130, are bound to the promoter in quiescent liver. MAT2A activation is accompanied by changes in the binding of histone-modifying enzymes to the promoter. Interestingly, p130 is not displaced from MAT2A promoter during hepatocyte priming, but it is in the late expression of the gene at the G1-S transition. Finally, the transcription factor Sp1 seems to play a decisive role in MAT2A induction, as it binds the promoter when the gene is being actively transcribed. In summary, the present work shows that the molecular mechanism of MAT2A expression is different during G0-G1 or G1-S transition and this may be related to the distinct requirements of S-adenosylmethionine during liver regeneration.

The Id (inhibitor of DNA binding or inhibitor of differentiation) helix-loop-helix proteins are involved in the regulation of cell growth, differentiation and cancer. The fact that the molecular mechanisms of liver regeneration are not completely understood prompted us to study the fate of Id2 in proliferating liver. Id2 increases in liver regeneration after partial hepatectomy, following the early induction of its gene. Co-immunoprecipitation shows that Id2 forms a complex with E2F4, p130 and mSin3A in quiescent liver and all these components are present at the c-myc promoter as shown using ChIP (chromatin immunoprecipitation). Activation of c-myc during hepatocyte priming (G0-G1 transition) correlates with the dissociation of Id2 and HDAC (histone deacetylase), albeit p130 remains bound at least until 6 h. Moreover, as the G0-G1 transition progresses, Id2 and HDAC again bind the c-myc promoter concomitantly with the repression of this gene. The time course of c-myc binding to the Id2 promoter, as determined by ChIP assays is compatible with a role of the oncoprotein as a transcriptional inducer of Id2 in liver regeneration. Immunohistochemical analysis shows that Id2 also increases in proliferating hepatocytes after bile duct ligation. In this case, the pattern of Id2 presence in the c-myc promoter parallels that found in regenerating liver. Our results may suggest a control role for Id2 in hepatocyte priming, through a p130 dissociation-independent regulation of c-myc.

Dietary methionine is mainly metabolized in the liver where it is converted into S-adenosylmethionine (AdoMet), the main biologic methyl donor. This reaction is catalyzed by methionine adenosyltransferase I/III (MAT I/III), the product of MAT1A gene, which is exclusively expressed in this organ. It was first observed that serum methionine levels were elevated in experimental models of liver damage and in liver cirrhosis in human beings. Results of further studies showed that this pathological alteration was due to reduced MAT1A gene expression and MAT I/III enzyme inactivation associated with liver injury. Synthesis of AdoMet is essential to all cells in the organism, but it is in the liver where most of the methylation reactions take place. The central role played by AdoMet in cellular function, together with the observation that AdoMet administration reduces liver damage caused by different agents and improves survival of alcohol-dependent patients with cirrhosis, led us to propose that alterations in methionine metabolism could play a role in the onset of liver disease and not just be a consequence of it. In the present work, we review the recent findings that support this hypothesis and highlight the mechanisms behind the hepatoprotective role of AdoMet.

S-adenosylmethionine (AdoMet) is an essential compound in cellular transmethylation reactions and a precursor of polyamine and glutathione synthesis in the liver. In liver injury, the synthesis of AdoMet is impaired and its availability limited. AdoMet administration attenuates experimental liver damage, improves survival of alcoholic patients with cirrhosis, and prevents experimental hepatocarcinogenesis. Apoptosis contributes to different liver injuries, many of which are protected by AdoMet. The mechanism of AdoMet's hepatoprotective and chemopreventive effects are largely unknown. The effect of AdoMet on okadaic acid (OA)-induced apoptosis was evaluated using primary cultures of rat hepatocytes and human hepatoma cell lines. AdoMet protected rat hepatocytes from OA-induced apoptosis dose dependently. It attenuated mitochondrial cytochrome c release, caspase 3 activation, and poly(ADP-ribose) polymerase cleavage. These effects were independent from AdoMet-dependent glutathione synthesis, and mimicked by 5'-methylthioadenosine (MTA), which is derived from AdoMet. Interestingly, AdoMet and MTA did not protect HuH7 cells from OA-induced apoptosis; conversely both compounds behaved as proapoptotic agents. AdoMet's proapoptotic effect was dose dependent and observed also in HepG2 cells. In conclusion, AdoMet exerts opposing effects on apoptosis in normal versus transformed hepatocytes that could be mediated through its conversion to MTA. These effects may participate in the hepatoprotective and chemopreventive properties of this safe and well-tolerated drug.

Genome sequence analysis reveals that all organisms synthesize S-adenosylmethionine (AdoMet) and that a large fraction of all genes is AdoMet-dependent methyltransferases. AdoMet-dependent methylation has been shown to be central to many biological processes. Up to 85% of all methylation reactions and as much as 48% of methionine metabolism occur in the liver, which indicates the crucial importance of this organ in the regulation of blood methionine. Of the two mammalian genes (MAT1A, MAT2A) that encode methionine adenosyltransferase (MAT, the enzyme that makes AdoMet), MAT1A is specifically expressed in adult liver. It now appears that growth factors, cytokines, and hormones regulate liver MAT mRNA levels and enzyme activity and that AdoMet should not be viewed only as an intermediate metabolite in methionine catabolism, but also as an intracellular control switch that regulates essential hepatic functions such as regeneration, differentiation, and the sensitivity of this organ to injury. The aim of this review is to integrate these recent findings linking AdoMet with liver growth, differentiation, and injury into a comprehensive model. With the availability of AdoMet as a nutritional supplement and evidence of its beneficial role in various liver diseases, this review offers insight into its mechanism of action.

BACKGROUND & AIMS: Of the 2 genes (MAT1A, MAT2A) encoding methionine adenosyltransferase, the enzyme that synthesizes S-adenosylmethionine, MAT1A, is expressed in liver, whereas MAT2A is expressed in extrahepatic tissues. In liver, MAT2A expression associates with growth, dedifferentiation, and cancer. Here, we identified the beta subunit as a regulator of proliferation in human hepatoma cell lines. The beta subunit has been cloned and shown to lower the K(m) of methionine adenosyltransferase II alpha2 (the MAT2A product) for methionine and to render the enzyme more susceptible to S-adenosylmethionine inhibition. METHODS: Methionine adenosyltransferase II alpha2 and beta subunit expression was analyzed in human and rat liver and hepatoma cell lines and their interaction studied in HuH7 cells. beta Subunit expression was up- and down-regulated in human hepatoma cell lines and the effect on DNA synthesis determined. RESULTS: We found that beta subunit is expressed in rat extrahepatic tissues but not in normal liver. In human liver, beta subunit expression associates with cirrhosis and hepatoma. beta Subunit is expressed in most (HepG2, PLC, and Hep3B) but not all (HuH7) hepatoma cell lines. Transfection of beta subunit reduced S-adenosylmethionine content and stimulated DNA synthesis in HuH7 cells, whereas down-regulation of beta subunit expression diminished DNA synthesis in HepG2. The interaction between methionine adenosyltransferase II alpha2 and beta subunit was demonstrated in HuH7 cells. CONCLUSIONS: Our findings indicate that beta subunit associates with cirrhosis and cancer providing a proliferative advantage in hepatoma cells through its interaction with methionine adenosyltransferase II alpha2 and down-regulation of S-adenosylmethionine levels.

Methionine metabolism starts with the formation of S-adenosylmethionine (AdoMet), the most important biological methyl donor. This reaction is catalyzed by methionine adenosyltransferase (MAT). MAT is the product of two different genes: MAT1A, which is expressed only in the adult liver, and MAT2A, which is widely distributed, expressed in the fetal liver, and replaces MAT1A in hepatocarcinoma. In the liver, preservation of high expression of MAT1A and low expression of MAT2A is critical for the maintenance of a functional and differentiated organ. Here we describe that in cultured rat hepatocytes MAT1A expression progressively decreased, as described for other liver-specific genes, and MAT2A expression was induced. We find that this switch in gene expression was prevented by adding AdoMet to the culture medium. We also show that in cultured hepatocytes with decreased MAT1A expression AdoMet addition markedly increased MAT1A transcription in a dose-dependent fashion. This effect of AdoMet was mimicked by methionine, and blocked by 3-deazaadenosine and L-ethionine, but not D-ethionine, indicating that the effect was specific and mediated probably by a methylation reaction. These findings identify AdoMet as a key molecule that differentially regulates MAT1A and MAT2A expression and helps to maintain the differentiated status of the hepatocyte.

We investigated the modulation of rat liver S-adenosylmethionine (SAM) synthetase in a model of acute sepsis. Our results show that animals treated with bacterial lipopolysaccharide experience a marked decrease in liver SAM synthetase activity. No changes were detected in the hepatic levels of SAM synthetase protein, suggesting that inactivation of the existing enzyme was the cause of the observed activity loss. Lipopolysaccharide treatment resulted in the expression of calcium-independent/cytokine-inducible nitric oxide (NO) synthase in liver and the accumulation in plasma of the NO- derived species nitrite and nitrate. NO implication in the in vivo regulation of SAM synthetase was evaluated in animals treated with the NO donor molecule 3-morpholinosydnonimine. The analysis of liver enzymatic activity, along with protein and messenger RNA levels yielded results similar to those obtained with lipopolysaccharide treatment. To assess directly the sensitivity of SAM synthetase to NO, the rat liver-purified high-and low-molecular weight forms of the enzyme were exposed to various doses of 3-morpholinosydnonimine and other NO donors such as S-nitroso-N-acetylpenicillamine, resulting in a dose- dependent inhibition of enzymatic activity. This effect was reversed by addition of the reducing agents β-mercaptoethanol and glutathione. Finally, cysteine 121 was identified as the site of molecular interaction between NO and rat liver SAM synthetase that is responsible for the inhibition of the enzyme. To reach this conclusion, the 10 cysteine residues of the enzyme were changed to serine by site-directed mutagenesis, and the effect of NO on the various recombinant enzymes was measured., Supported by grants of Fondo de Investigaciones Sanitarias (94/0231 and 95/0966), Dirección General de Investigaciones Científicas (PB 94/0087, PB 93/070), and EC Science Program (SCI*-CT92-0780), Europharma.

One of the features of liver cirrhosis is an abnormal metabolism of methionine--a characteristic that was described more than a half a century ago. Thus, after an oral load of methionine, the rate of clearance of this amino acid from the blood is markedly impaired in cirrhotic patients compared with that in control subjects. Almost 15 y ago we observed that the failure to metabolize methionine in cirrhosis was due to an abnormally low activity of the enzyme methionine adenosyltransferase (EC 2.5.1.6). This enzyme converts methionine, in the presence of ATP, to S-adenosyl-L-methionine (SAMe), the main biological methyl donor. Since then, it has been suspected that a deficiency in hepatic SAMe may contribute to the pathogenesis of the liver in cirrhosis. The studies reviewed here are consistent with this hypothesis.

Background Patients with fibromyalgia syndrome (FMS) have autonomic nervous system (ANS) related disorder 1 . The orthostatic stimulus is an important method for the assessment of neurocardiac integrity 2 . However, little is known about the cardiac autonomic response to the active standing test in women with FMS. Objectives To evaluate the cardiac autonomic control response to the active standing test in women with FMS. Methods Ten women with FMS (FMSG n=10) and ten healthy women (HG n=10) took part in the study. The volunteers were submitted to the recording of RR intervals (RRi) during 15 min in supine and 15 min in orthostatic (active standing) positions. RRi were recorded by a heart rate monitor. The parameters of the frequency domain were determined by the heart rate variability (HRV) spectral analysis, obtained in low frequency (LF, 0.04–0.15 Hz) and high frequency bands (HF, 0.15–0.4 Hz) in normalized units (n.u.) and LF/HF ratio 3 . Results The results are shown in table 1. There were significant group x posture interaction for LF (n.u.) and HF (n.u.). Post hoc analysis revealed that the HG increased LF (n.u.) and decreased the HF (n.u.) during active standing, compared to the supine position. On the other hand, the FMSG presented no significant differences between supine and orthostatic position. Regarding between group comparisons, FMSG presented higher LF (n.u.) and lower HF (n.u.) at supine position. Conclusions FMSG showed cardiac autonomic dysfunction at supine position, characterized by higher sympathetic and lower parasympathetic cardiac autonomic modulation. In addition, FMSG present a blunted cardiac autonomic control response to the active standing, characterized by a lack of cardiac sympathetic modulation increase and parasympathetic decrease. Therefore, the neurocardiac integrity seems to be compromised in the FMSG. References Zamuner AR, Forti M, Andrade CP, Avila MA, Silva E. Respiratory Sinus Arrhythmia and its Association with Pain in Women with Fibromyalgia Syndrome. 2015 a.[Epub ahead of print]. Furlan R, Colombo S, Perego F, Atzeni F, Diana A, Barbic F, et al. Abnormalities of cardiovascular neural control and reduced orthostatic tolerance in patients with primary fibromyalgia. J Rheumatol. 2005;32:1787–1793. Task Force. Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task force of the European society of cardiology and the North American Society of pacing and electrophysiology. Circulation. 1996;93:1043–1065. Acknowledgement This study was supported Sao Paulo Research Foundation (FAPESP), grants #2011/22122–5, #2013/17504–1 and 2015/23449–9 and by the National Council for Scientific and Technological Development (CNPq), grants no. 483032/2012–3 and 307187/2013–6. Disclosure of Interest None declared

Background Several studies have shown that autonomic dysfunction plays an important role in the fibromyalgia syndrome (FMS). 1–3 Recent studies have used the active standing test to assess the cardiovascular autonomic control responses to the orthostatic stimulus in several disorders, including FMS. 4 However, there are few studies correlating symptoms and clinical factors with cardiovascular autonomic dysfunction. Objectives To assess the relationship between the impact of fibromyalgia on quality of life and cardiac autonomic control response to the active standing test. Methods Ten women (47.9±7.3 years old) with clinical diagnosis of FMS took part in the study. Diagnosis followed the criteria established by the American College of Rheumatology. 5 All participants answered the fibromyalgia impact questionnaire (FIQ) 6 and underwent the recording of RR intervals (RRi) using a transmitter belt. The RRi were recorded for 15 min in resting supine position and during 15 min in an orthostatic position reached by active standing. The cardiac autonomic control was assessed by indices computed via spectral analysis of RRi in low frequency (LF, 0.04–0.15 Hz) and high frequency bands (HF, 0.15–0.4 Hz). To quantify the magnitude of cardiac autonomic response to the orthostatic stimulus, the delta between values obtained in supine and standing positions was calculated for all variables. Changes induced by the orthostatic stimulus were evaluated by Wilcoxon test. Spearman9s coefficient was used to assess the association between the delta of the HRV indices and the FIQ scores. α =5%. Results There were no significant differences between the supine and standing positions in any of the spectral indices. Positive correlation was found between FIQ scores and HF (n.u.) (r =0.67; p=0.03). Negative correlations were observed between the FIQ scores and LF (n.u.) index (r = -0.67; p=0.03, Figure 1B) and LF/HF ratio (r = -0.73; p=0.016, Figure 1C). Conclusions The results showed that the larger the magnitude of the cardiac autonomic adjustments to the gravitational stimulus, the smaller the impact of FMS on quality of life. References Martinez-Lavin M, Hermosillo AG. Autonomic nervous system dysfunction may explain the multisystem features of fibromyalgia. Semin Arthritis Rheum. 2000;29:197–199. Furlan R, Colombo S, Perego F, et al. Abnormalities of cardiovascular neural control and reduced orthostatic tolerance in patients with primary fibromyalgia. J Rheumatol. 2005;32:1787–1793. Zamuner AR, Forti M, Andrade CP, Avila MA, Silva E. Respiratory sinus arrhythmia and its association with pain in women with fibromyalgia syndrome. 2015. doi: 10.1111/papr.12321 Zamuner AR, Porta A, Andrade CP, Marchi A, Forti M, Furlan R, Barbic F, Catai AM, Silva E. Cardiovascular control in women with fibromyalgia syndrome: do causal methods provide nonredundant information compared with more traditional approaches? Am J Physiol Regul Integr Comp Physiol. 2015;309:R79–R84. doi:10.1152/ajpregu.00012.2015 Wolfe F, Smythe HA, Yunus MB, et al. Fibromyalgia. Rheum Dis Clin North Am. 1990;16:681–698. Marques AP, Santos AMB, Assumpcao A, Matsutani LA, Lage LV, Pereira CAB. Validation of the Brazilian version of the Fibromyalgia Impact Questionnaire (FIQ). Braz J Rheumatol. 2006;46:24–31. Acknowledgement This study was supported Sao Paulo Research Foundation (FAPESP), grants #2011/22122–5 and #2015/08445–7. Disclosure of Interest None declared

Electron Spin Resonance (ESR) experiments in the filled Cei1-xYbxFe4P12(x ≲ 0.0023) skutterudite compounds of Thcubic symmetry (Im3) reveal the coexistence of two distinct Yb3+sites with large difference in their site occupation, hyperfine interaction and temperature dependence of the ESR parameters. These results suggest a scenario where the oversized (Fe2P3)4-cages of the Ce1-xYbxFe4P12compounds are occupied with small number of on-center-Yb3+ions and a distribution of highly occupied off-center-Yb3+ions, rattling at ∼1 GHz and above ∼20 GHz, respectively. © 2010 IOP Publishing Ltd.