High sucrose intake in rats is associated with increased ACE2 and angiotensin-(1-7) levels in the adipose tissue

Sucrose-fed rats, a model of metabolic syndrome, are characterized by insulin resistance, obesity, hypertension, and high plasma levels of triacylglycerols and angiotensin II (Ang II). However, whether tissue renin-angiotensin system (RAS) is altered in metabolic syndrome is unclear. To study this issue, food ad libitum and water (C) or 20% sucrose solution (SC) were given to adult male Wistar rats, for 30 days. Body weight (BW), blood pressure (BP), epididymal adipose tissue (EPI) mass, rate of in vivo fatty acid (FA) synthesis in EPI, circulating glucose, insulin, leptin, angiotensins I and II, triacylglycerols, and plasma renin (PRA) and angiotensin-converting enzyme (ACE) activities were evaluated. In kidneys and EPI, gene and protein expression of type 1 (AT(1)) and 2 (AT(2)) Ang II receptors, ACE, angiotensinogen (ACT) as well as protein expression of angiotensin-converting enzyme 2 (ACE2) were determined. In both tissues, Ang I, Ang II and Ang-(1-7) contents were also measured by HPLC. In SC rats higher BP, EPI mass, circulating triacylglycerols, insulin, leptin, PRA and, Ang II were found. In EPI, the rate of in vivo FA synthesis was associated with increased Ang-(1-7), protein expression of AT(1) and AT(2) receptors, ACE2, ACT, and gene expression of ACT although a reduction in ACE activity and in adipose Ang I and Ang II contents was observed. In kidneys, AT(1) and AT(2), ACE and ACT gene and protein expression as well as protein expression of ACE2 were unaltered while Ang II, Ang-(1-7) and ACE activity increased. These RAS component changes seem to be tissue specific and possibly are related to enhancement of FA synthesis, EPI mass and hypertension. (C) 2010 Elsevier B.V. All rights reserved.

Characterisation of the recently cloned rat noradrenaline transporter - Comparison with bovine and human transporters

The aims of this study were to characterize the recently cloned rat norepinephrine transporter (NET) in more detail and in particular to study possible species differences in its pharmacological properties compared with the human and bovine NETs. The study was carried out by measuring the uptake of [3H]norepinephrine in COS-7 cells expressing the NET after transient transfection with rat, human, or bovine NET cDNA. There were small but significant differences between the rat NET and the human or bovine NETs with respect to the affinities of sodium ions (greater for rat than for bovine) of the substrates norepinephrine, epinephrine, and 1-methyl-4-phenylpyridinium (greater for human than for rat), and of the inhibitor cocaine (greater for human and bovine than for rat), whereas the affinities of dopamine and of most inhibitors, including tricyclic antidepressants, showed no species differences. The fact that the affinities for some substrates, cocaine and sodium ions exhibited small but significant interspecies differences among the rat, human, and bovine NETs suggests that ligand recognition, the translocation process, and sodium ion dependence are influenced differentially by just a few amino acid exchanges in the primary sequences of the transporters. On the other hand, the lack of any major differences in the pharmacological properties of the rat, human, and bovine NETs in this study suggests that data obtained in previous studies on rat tissues and bovine cells can be extrapolated, in all except the most quantitative analyses, to the properties of the human NET.

Novel fed-batch strategy for the production of insulin-like growth factor 1 (IGF-1)

The production of Long-R-3-IGF-1 (an IGF-1 fusion analog) by constant-rate, fed-batch fermentation of Escherichia coli yielded 2.6 g fusion protein/L, corresponding to an actual IGF-1 concentration of 2.2 g/L. A novel strategy employing three distinct feeding stages was developed which raised product concentration to 4.3 g/L (3.6 g/L of IGF-1) while minimising glucose and acetate accumulation. This improved productivity was not accompanied by an increase in inclusion body size.

A randomized controlled trial comparing a computer-assisted insulin infusion protocol with a strict and a conventional protocol for glucose control in critically ill patients

Purpose: The objective of this study is to evaluate blood glucose (BG) control efficacy and safety of 3 insulin protocols in medical intensive care unit (MICU) patients. Methods: This was a multicenter randomized controlled trial involving 167 MICU patients with at least one BG measurement +/- 150 mg/dL and one or more of the following: mechanical ventilation, systemic inflammatory response syndrome, trauma, or burns. The interventions were computer-assisted insulin protocol (CAIP), with insulin infusion maintaining BG between 100 and 130 mg/dL; Leuven protocol, with insulin maintaining BG between 80 and 110 mg/dL; or conventional treatment-subcutaneous insulin if glucose > 150 mg/dL. The main efficacy outcome was the mean of patients` median BG, and the safety outcome was the incidence of hypoglycemia (<= 40 mg/dL). Results: The mean of patients` median BG was 125.0, 127.1, and 158.5 mg/dL for CAIP, Leuven, and conventional treatment, respectively (P = .34, CAIP vs Leuven; P < .001, CAIP vs conventional). In CAIP, 12 patients (21.4%) had at least one episode of hypoglycemia vs 24 (41.4%) in Leuven and 2 (3.8%) in conventional treatment (P = .02, CAIP vs Leuven; P = .006, CAIP vs conventional). Conclusions: The CAIP is safer than and as effective as the standard strict protocol for controlling glucose in MICU patients. Hypoglycemia was rare under conventional treatment. However, BG levels were higher than with IV insulin protocols. (C) 2009 Elsevier Inc. All rights reserved.

(1)H magnetic resonance spectroscopy imaging of the hippocampus in patients with panic disorder

Recent theories of panic disorder propose an extensive involvement of limbic system structures, such as the hippocampus, in the pathophysiology of this condition. Despite this, no prior study has examined exclusively the hippocampal neurochemistry in this disorder. The current study used proton magnetic resonance spectroscopy imaging ((1)H-MRSI) to examine possible abnormalities in the hippocampus in panic disorder patients. Participants comprised 25 panic patients and 18 psychiatrically healthy controls. N-acetylaspartate (NAA, a putative marker of neuronal viability) and choline (Cho, involved in the synthesis and degradation of cell membranes) levels were quantified relative to creatine (Cr, which is thought to be relatively stable among individuals and in different metabolic condition) in both right and left hippocampi. Compared with controls, panic patients demonstrated significantly lower NAA/Cr in the left hippocampus. No other difference was detected. This result is consistent with previous neuroimaging findings of hippocampal alterations in panic and provides the first neurochemical evidence suggestive of involvement of this structure in the disorder. Moreover, lower left hippocampal NAA/Cr in panic disorder may possibly reflect neuronal loss and/or neuronal metabolic dysfunction, and could be related to a deficit in evaluating ambiguous cues. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Increased expression of monocarboxylate transporters 1, 2, and 4 in colorectal carcinomas

Tumour cells are known to be highly glycolytic, thus producing high amounts of lactic acid. Monocarboxylate transporters (MCTs), by promoting the efflux of the accumulating acids, constitute one of the most important mechanisms in the maintenance of tumour intracellular pH. Since data concerning MCT expression in colorectal carcinomas (CRC) are scarce and controversial, the present study aimed to assess the expressions of MCT1, 2, and 4 in a well characterized series of CRC and assess their role in CRC carcinogenesis. CRC samples (126 cases) were analyzed for MCT1, MCT2, and MCT4 immunoexpression and findings correlated with clinico-pathological parameters. Expression of all MCT isoforms in tumour cells was significantly increased when compared to adjacent normal epithelium. Remarkably, there was a significant gain of membrane expression for MCT1 and MCT4 and loss of plasma membrane expression for MCT2 in tumour cells. Plasma membrane expression of MCT1 was directly related to the presence of vascular invasion. This is the larger study on MCT expression in CRC and evaluates for the first time its clinico-pathological significance. The increased expression of these transporters suggests an important role in CRC, which might justify their use, especially MCT1 and MCT4, as targets in CRC drug therapy.

Bariatric Surgery in Adolescents: Preliminary 1-year Results with a Novel Technique (Santoro III)

Background Bariatric surgery (BS) was recognized as the only treatment for morbid obesity in adolescents. Classic surgical procedures are based on mechanical restriction and/or malabsorption, resulting in a large number of possible complications and demanding lifelong medical attention. A novel BS design, the Santoro III procedure, relies on modifying secretion of the satiogenic hormones GLP-1 and PYY. This approach avoids common BS complications such as prostheses, narrow anastomoses, excluded segments, and malabsorption. This study describes the 1-year follow-up of the first ten adolescents operated on using the Santoro III technique in a pediatric surgical service. Methods Ten adolescents, mean age 16.1 +/- 1.7 years with body mass index (BMI) greater than 40 kg/m(2) (range 44 to 72 kg/m(2)), refractory to at least 2 years of medical weight loss treatment were selected by a multidisciplinary team to undergo BS. This operation consists of a sleeve gastrectomy with enteroomentectomy and partial gastro-ileal derivation. Results After 1 year, mean body weight decreased from 140.3 to 88.6 kg, and BMI decreased from 52.8 +/- 9.5 kg/m(2) to 33.4 +/- 7.7 kg/m(2), with percent of excess BMI lost as 83.9 +/- 17.1%. Glucose, insulin, total cholesterol, LDL-cholesterol, and triglyceride levels decreased significantly, while HDL-cholesterol, hemoglobin, and albumin levels remained unchanged. There were no mortalities or reoperations. The two complications that presented during the trial (intraperitoneal abscess and polyneuritis) resolved with medical treatment without sequelae. All the patients returned to their normal activities and their BMI began to stabilize approximately 2 years following surgery. Conclusions The Santoro III procedure is an attractive option for adolescent BS, with promising 1-year follow-up results. These initial studies should be monitored for long-term outcomes and confirmed on a larger group of patients.

Effects of anti-TNF therapy on glucose metabolism in patients with ankylosing spondylitis, psoriatic arthritis or juvenile idiopathic arthritis

The objective of this study was to evaluate the influence of anti-tumor necrosis factor (anti-TNF) in juvenile idiopathic arthritis (DA), ankylosing spondylitis (AS) or psoriatic arthritis (PsA). Sixty-two patients were investigated: 7 DA; 37 AS; and 18 PsA. Caucasian race accounted for 79% and 29% were female. Mean age was 40.4 +/- 12.6years. None of the patients had a history of diabetes, and none had used oral hypoglycemic agents or insulin. Treatment was with adalimumab, infliximab and etanercept. Glucose, inflammatory markers and prednisone dose were assessed at baseline, as well as after three and six months of treatment. The mean erythrocyte sedimentation rate was significantly lower at three months and six months than at baseline (13.7 +/- 18.0 and 18 +/- 22.5 vs. 27.9 +/- 23.4 mm; p = 0.001). At baseline, three months and six months, we found the following: mean C-reactive protein levels were comparable (22.1 +/- 22.7, 14.5 +/- 30.7 and 16.0 +/- 23.8 mg/L, respectively; p = 0.26); mean glucose levels remained unchanged (90.8 +/- 22.2 mg/dl, 89.5 +/- 14.6 mg/dl and 89.8 +/- 13.6 mg/dl, respectively; p = 0.91); and mean prednisone doses were low and stable (3.9 +/- 4.9 mg/day, 3.7 +/- 4.8 mg/day and 2.6 +/- 4.0 mg/day, respectively; p = 0.23). During the first six months of treatment, anti-TNF therapy does not seem to influence glucose metabolism in JIA, AS or PsA. (C) 2010 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.

Mechanisms mediating the diuretic and natriuretic actions of the incretin hormone glucagon-like peptide-1

Crajoinas RO, Oricchio FT, Pessoa TD, Pacheco BP, Lessa LM, Malnic G, Girardi AC. Mechanisms mediating the diuretic and natriuretic actions of the incretin hormone glucagon-like peptide-1. Am J Physiol Renal Physiol 301: F355-F363, 2011. First published May 18, 2011; doi: 10.1152/ajprenal.00729.2010.-Glucagon-like peptide-1 (GLP-1) is a gut incretin hormone considered a promising therapeutic agent for type 2 diabetes because it stimulates beta cell proliferation and insulin secretion in a glucose-dependent manner. Cumulative evidence supports a role for GLP-1 in modulating renal function; however, the mechanisms by which GLP-1 induces diuresis and natriuresis have not been completely established. This study aimed to define the cellular and molecular mechanisms mediating the renal effects of GLP-1. GLP-1 (1 mu g.kg(-1).min(-1)) was intravenously administered in rats for the period of 60 min. GLP-1-infused rats displayed increased urine flow, fractional excretion of sodium, potassium, and bicarbonate compared with those rats that received vehicle (1% BSA/saline). GLP-1-induced diuresis and natriuresis were also accompanied by increases in renal plasma flow and glomerular filtration rate. Real-time RT-PCR in microdissected rat nephron segments revealed that GLP-1 receptor-mRNA expression was restricted to glomerulus and proximal convoluted tubule. In rat renal proximal tubule, GLP-1 significantly reduced Na(+)/H(+) exchanger isoform 3 (NHE3)-mediated bicarbonate reabsorption via a protein kinase A (PKA)-dependent mechanism. Reduced proximal tubular bicarbonate flux rate was associated with a significant increase of NHE3 phosphorylation at the PKA consensus sites in microvillus membrane vesicles. Taken together, these data suggest that GLP-1 has diuretic and natriuretic effects that are mediated by changes in renal hemodynamics and by downregulation of NHE3 activity in the renal proximal tubule. Moreover, our findings support the view that GLP-1-based agents may have a potential therapeutic use not only as antidiabetic drugs but also in hypertension and other disorders of sodium retention.

Candidate-Gene Approach in Posttraumatic Stress Disorder After Urban Violence: Association Analysis of the Genes Encoding Serotonin Transporter, Dopamine Transporter, and BDNF

Posttraumatic stress disorder (PTSD) is a prevalent, disabling anxiety disorder marked by behavioral and physiologic alterations which commonly follows a chronic course. Exposure to a traumatic event constitutes a necessary, but not sufficient, factor. There is evidence from twin studies supporting a significant genetic predisposition to PTSD. However, the precise genetic loci still remain unclear. The objective of the present study was to identify, in a case-control study, whether the brain-derived neurotrophic factor (BDNF) val66met polymorphism (rs6265), the dopamine transporter (DAT1) three prime untranslated region (3`UTR) variable number of tandem repeats (VNTR), and the serotonin transporter (5-HTTPRL) short/long variants are associated with the development of PTSD in a group of victims of urban violence. All polymorphisms were genotyped in 65 PTSD patients as well as in 34 victims of violence without PTSD and in a community control group (n = 335). We did not find a statistical significant difference between the BDNF val66met and 5-HTTPRL polymorphism and the traumatic phenotype. However, a statistical association was found between DAT1 3`UTR VNTR nine repeats and PTSD (OR = 1.82; 95% CI, 1.20-2.76). This preliminary result confirms previous reports supporting a susceptibility role for allele 9 and PTSD.

A catecholamine transporter from the human parasite Schistosoma mansoni with low affinity for psychostimulants

The trematode Schistosoma mansoni is the primary cause of schistosomiasis, a devastating neglected tropical disease that affects 200 million individuals. Identifying novel therapeutic targets for the treatment of schistosomiasis is therefore of great public interest. The catecholamines norepinephrine (NE) and dopamine (DA) are essential for the survival of the parasite as they cause muscular relaxation and a lengthening in the parasite and thereby control movement. Here we characterize a novel dopamine/norepinephrine transporter (SmDAT) gene transcript, from S. mansoni. The SmDAT is expressed in the adult form and in the sporocyst form (infected snails) of the parasite, and also in the egg and miracidium stage. It is absent in the cercariae stage but curiously a transcript missing the exon encoding transmembrane domain 8 was identified in this stage. Heterologous expression of the cDNA in mammalian cells resulted in saturable, dopamine transport activity with an apparent affinity for dopamine comparable to that of the human dopamine transporter. Efflux experiments reveal notably higher substrate selectivity compared with its mammalian counterparts as amphetamine is a much less potent efflux elicitor against SmDAT compared to the human DAT. Pharmacological characterization of the SmDAT revealed that most human DAT inhibitors including psychostimulants such as cocaine were significantly less potent in inhibiting SmDAT. Like DATs from other simpler organisms the pharmacology for SmDAT was more similar to the human norepinephrine transporter. We were not able to identify other dopamine transporting carriers within the completed parasite genome and we hypothesize that the SmDAT is the only catecholamine transporter in the parasite and could be responsible for not only clearing DA but also NE. (C) 2011 Elsevier B.V. All rights reserved.

Two allelic isoforms of the serotonin transporter from Schistosoma mansoni display electrogenic transport and high selectivity for serotonin

The human blood fluke Schistosoma mansoni is the primary cause of schistosomiasis, a debilitating disease that affects 200 million individuals in over 70 countries. The biogenic amine serotonin is essential for the survival of the parasite and serotonergic proteins are potential novel drug targets for treating schistosomiasis. Here we characterize two novel serotonin transporter gene transcripts, SmSERT-A and SmSERT-B, from S. mansoni. Southern blot analysis shows that the two mRNAs are the products of different alleles of a single SmSERT gene locus. The two SmSERT forms differ in three amino acid positions near the N-terminus of the protein. Both SmSERTs are expressed in the adult form and in the sporocyst form (infected snails) of the parasite, but are absent from all other stages of the parasite`s complex life cycle. Heterologous expression of the two cDNAs in mammalian cells resulted in saturable, sodium-dependent serotonin transport activity with an apparent affinity for serotonin comparable to that of the human serotonin transporter. Although the two SmSERTs are pharmacologically indistinguishable from each other, efflux experiments reveal notably higher substrate selectivity for serotonin compared with their mammalian counterparts. Several well-established substrates for human SERT including (+/-)MDMA, S-(+)amphetamine, RU 24969, and m-CPP are not transported by SmSERTs, underscoring the higher selectivity of the schistosomal isoforms. Voltage-clamp recordings of SmSERT substrate-elicited currents confirm the substrate selectivity observed in efflux experiments and suggest that it may be possible to exploit the electrogenic nature of SmSERT to screen for compounds that target the parasite in vivo. (C) 2009 Elsevier B.V. All rights reserved.

Autologous stem cell transplantation for early type 1 diabetes mellitus

Type 1 diabetes mellitus (T1DM) is the result of the autoimmune response against pancreatic insulin producing cells. This autoimmune response begins months or even years before the first presentation of signs and symptoms of hyperglycemia and at the time of clinical diagnosis near 30% of -cell mass still remains. In daily clinical practice, the main therapeutic option for T1DM is multiple subcutaneous insulin injections that are shown to promote tight glucose control and reduce much of diabetic chronic complications, especially microvascular complications. Another important aspect related to long-term complications of diabetes is that patients with initially larger -cell mass suffer less microvascular complications and less hypoglycemic events than those patients with small -cell mass. In face of this, -cell preservation is another important target in the management of type 1 diabetes and its related complications. For many years, various immunomodulatory regimens were tested aiming at blocking autoimmunity against -cell mass and at promoting -cell preservation, mainly in secondary prevention trials. In this review, we summarize some of the most important studies involving -cell preservation by immunomodulation and discuss our preliminary data on autologous nonmyeloablative hematopoietic stem cell transplantation in newly-diagnosed T1DM.

Discordant Nadir GH After Oral Glucose and IGF-I Levels on Treated Acromegaly: Refining the Biochemical Markers of Mild Disease Activity

Biochemical markers for remission on acromegaly activity are controversial. We studied a subset of treated acromegalic patients with discordant nadir GH levels after oral glucose tolerance test (oGTT) and IGF-I values to refine the current consensus on acromegaly remission. We also compared GH results by two GH immunoassays. From a cohort of 75 treated acromegalic patients, we studied 13 patients who presented an elevated IGF-I despite post-oGTT nadir GH of <= 1 mu g/l. The 12-h daytime GH profile (GH-12 h), nadir GH after oGTT, and basal IGF-I levels were studied in patients and controls. Bland-Altman method showed high concordance between GH assays. Acromegalic patients showed higher mean GH-12 h values (0.71+/-0.36 vs. 0.31+/-0.28 mu g/l; p<0.05) and nadir GH after oGTT (0.48+/-0.32 vs. 0.097+/-0.002 mu g/l; p<0.05) as compared to controls. Nadir GH correlated with mean GH-12 h (r=0.92, p<0.05). The mean GH-12 h value from upper 95% CI of controls (0.54 mu g/l) would correspond to a theoretical normal nadir GH of <= 0.27 mu g/l. Patients with GH nadir <= 0.3 mu g/l had IGF-I between 100-130% ULNR (percentage of upper limit of normal range) and mean GH-12 h of 0.35+/-0.15, and patients with GH nadir >0.3 and <= 1 mu g/l had IGF-I >130% ULNR and mean GH-12 h of 0.93+/-0.24 mu g/l. Our data integrate daytime GH secretion, nadir GH after oGTT, and plasma IGF-I concentrations showing a continuum of mild residual activity in a subgroup of treated acromegaly with nadir GH values <= 1 mu g/l. The degree of increased IGF-I levels and nadir GH after oGTT are correlated with the subtle abnormalities of daytime GH secretion.

Brachial artery pulsatility index change 1 minute after 5-minute forearm compression - Comparison with flow-mediated dilatation

Objective. Endothelial impairment evaluation by sonographic measurement of flow-mediated dilatation (FMD) has become broadly used. However, this method has 2 main caveats: the dilatation depends on the baseline arterial diameter, and a high precision level is required. Vasodilatation leads to an amplified fall in impedance. We hypothesized that assessment of the pulsatility index change (PI-C) 1 minute after 5-minute forearm compression might evaluate that fall in impedance. The aim of this study was to compare the PI-C with FMD. Methods. Flow-mediated dilatation and the PI-C were assessed in 51 healthy women aged between 35.1 and 67.1 years. We correlated both FMD and the PI-C with age, body mass index, waist circumference, cholesterol level, high-density lipoprotein level, glucose level, systolic and diastolic blood pressure, pulse pressure, brachial artery diameter, simplified Framingham score, intima-media thickness, and carotid stiffness index. Intraclass correlation coefficients between 2 FMD and PI-C measurements were also examined. Results. Only FMD correlated with baseline brachial diameter (r=-0.53). The PI-C had a high correlation with age, body mass index, waist circumference, cholesterol level, systolic blood pressure, pulse pressure, simplified Framingham score, and intima-media thickness. The correlation between FMD and the PI-C was high (r=-0.66). The PI-C had a higher intraclass correlation coefficient (0.991) than FMD (0.836) but not brachial artery diameter (0.989). Conclusions. The PI-C had a large correlation with various markers of cardiovascular risk. Additionally, PI-C measurement does not require offline analysis, extra software, or electrocardiography We think that the PI-C could be considered a marker of endothelial function. However, more studies are required before further conclusions.