Isolated intrasplenic vascular calcifications in a child with type 1 diabetes mellitus‐‐‐A case report

We report a case of vascular calcifications in the spleen of a 7‐year‐old girl who was diagnosed with type 1 diabetes mellitus (DM). The possible etiology for vascular calcifications might be medial sclerosis associated with DM. To the best of our knowledge, this finding has not yet been reported in the literature. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45 :438–440, 2017     

Nationwide survey to compare the prevalence of transient elevation of liver transaminase during treatment of diabetic ketosis or ketoacidosis in new-onset acute and fulminant type 1 diabetes mellitus

Background aims. A mild increase in liver enzyme levels is sometimes observed in patients with diabetic ketosis or ketoacidosis. The aim of the present study was to assess the cause and prevalence of the elevation of liver transaminase levels in fulminant and acute-onset type 1 diabetic patients experiencing diabetic ketosis or ketoacidosis.

Methods. We analyzed data on the liver transaminase levels of 108 patients over 18 years of age with newly diagnosed type 1 diabetes complicated by ketosis or ketoacidosis. The data were collated from a nationwide survey on fulminant type 1 diabetes and retrospective medical records.

Results. Thirty-two (60.4%) out of the 53 patients suffering from fulminant type 1 diabetes were detected with transient elevation of liver transaminase (TELT) levels during the first month after initiation of insulin therapy; in the case of acute-onset type 1 diabetes, such an observation was noted in 16 (29.1%) out of 55 patients. Fatty liver was diagnosed in 20% of the patients, and 65% of these patients exhibited TELT. The dosage of insulin injected in these patients was significantly high.

Conclusions. High blood glucose and fatty liver may influence the elevation of liver transaminase levels during the treatment of new-onset type 1 diabetes.     

Branched chain amino acids supplementation modulates TGF‐β1/Smad signaling pathway and interleukins in CCl4‐induced liver fibrosis

The alterations and low levels of circulating branched chain amino acids (BCAAs), leucine, isoleucine, and valine, are associated with liver diseases. The study was designed to evaluate hepatoprotective effect of BCAAs on CCl₄‐induced liver fibrosis and to investigate the molecular mechanisms underlying these effects in rats. In all, 30 male rats were divided into three groups. Control group (n = 10) and CCl₄ group (n = 10), where rats were injected with CCl₄ (1 mL/kg of 0.5 : 1 v/v injected i.p. twice weekly for 12 weeks). In CCl₄ + BCAAs group (n = 10), rats were injected with similar doses of CCl₄ and supplemented with a mixture of 600 mg/kg BCAAs (2 : 1 : 1.2 leucine : isoleucine : valine) by oral gavage, three times/week for 12 weeks. Liver fibrosis was assessed by measuring total bilirubin, total protein, alanine aminotransferase, and aspartate aminotransferase, hydroxyproline content, and serum IL‐6 and IL‐10. Histopathologic studies and α‐smooth muscle actin (α‐SMA) were detected immunohistochemically in liver. Serum insulin level, blood glucose, liver malodialdehyde concentration (MDA), glutathione peroxidase, and superoxide dismutase (SOD) activities were quantified. TGF‐β1, Smad3, and Smad7 gene expressions were estimated by qRT‐PCR. BCAAs suppressed liver fibrosis induced by CCl₄ treatment. BCAAs modulated liver indices and downregulated TGF‐β1, Smad3, and Smad7 expressions in hepatocytes. BCAAs enhanced liver antioxidant enzyme activities (P < 0.001), reduced serum levels of TGF‐β1, IL‐6, and IL‐10 compared to CCL₄ group and ameliorated histopathologic changes in rat liver. BCAAs may have a protective role against liver fibrosis via antioxidant and anti‐inflammatory mechanisms.     

Angiostatin K1‐3 induces E‐selectin via AP1 and Ets1: a mediator for anti‐angiogenic action of K1‐3

Summary. Background: Angiostatin, a circulating angiogenic inhibitor, is an internal fragment of plasminogen and consists of several isoforms, K1‐3 included. We previously showed that K1‐3 was the most potent angiostatin to induce E‐selectin mRNA expression. The purpose of this study was to identify the mechanism responsible for K1‐3‐induced E‐selectin expression and investigate the role of E‐selectin in the anti‐angiogenic action of K1‐3. Methods and results: Quantitative real time RT‐PCR and Western blotting analyses confirmed a time‐dependent increase of E‐selectin mRNA and protein induced by K1‐3. Subcellular fractionation and immunofluorescence microscopy showed the co‐localization of K1‐3‐induced E‐selectin with caveolin 1 (Cav1) in lipid rafts in which E‐selectin may behave as a signaling receptor. Promoter‐driven reporter assays and site‐directed mutagenesis showed that K1‐3 induced E‐selectin expression via promoter activation and AP1 and Ets‐1 binding sites in the proximal E‐selectin promoter were required for E‐selectin induction. The in vivo binding of both protein complexes to the proximal promoter was confirmed by chromatin immunoprecipitation (ChIP). Although K1‐3 induced the activation of ERK1/2 and JNK, only repression of JNK activation attenuated the induction of E‐selectin by K1‐3. A modulatory role of E‐selectin in the anti‐angiogenic action of K1‐3 was manifested by both overexpression and knockdown of E‐selectin followed by cell proliferation assay. Conclusions: We show that K1‐3 induced E‐selectin expression via AP1 and Ets‐1 binding to the proximal E‐selectin promoter (?356/+1), which was positively mediated by JNK activation. Our findings also demonstrate E‐selectin as a novel target for the anti‐angiogenic therapy.     

The α‐granule proteome: novel proteins in normal and ghost granules in gray platelet syndrome

See also García Á. Clinical proteomics in platelet research: challenges ahead. This issue, pp 1784–5. Summary. Background: Deficiencies in granule‐bound substances in platelets cause congenital bleeding disorders known as storage pool deficiencies. For disorders such as gray platelet syndrome (GPS), in which thrombocytopenia, enlarged platelets and a paucity of α‐granules are observed, only the clinical and histologic states have been defined. Objectives: In order to understand the molecular defect in GPS, the α‐granule fraction protein composition from a normal individual was compared with that of a GPS patient by mass spectrometry (MS). Methods: Platelet organelles were separated by sucrose gradient ultracentrifugation. Proteins from sedimented fractions were separated by sodium dodecylsulfate polyacrylamide gel electrophoresis, reduced, alkylated, and digested with trypsin. Peptides were analyzed by liquid chromatography–tandem MS. Mascot was used for peptide/protein identification and to determine peptide false‐positive rates. Mass Sieve was used to generate and compare parsimonious lists of proteins. Results: As compared with control, the normalized peptide hits (NPHs) from soluble, biosynthetic α‐granule proteins were markedly decreased or undetected in GPS platelets, whereas the NPHs from soluble, endocytosed α‐granule proteins were only moderately affected. The NPHs from membrane‐bound α‐granule proteins were similar in normal platelets and GPS platelets, although P‐selectin and Glut3 were slightly decreased, consistent with immunoelectron microscopy findings in resting platelets. We also identified proteins not previously known to be decreased in GPS, including latent transforming growth factor‐β‐binding protein 1(LTBP1), a component of the transforming growth factor‐β (TGF‐β) complex. Conclusions: Our results support the existence of ‘ghost granules’ in GPS, point to the basic defect in GPS as failure to incorporate endogenously synthesized megakaryocytic proteins into α‐granules, and identify specific new proteins as α‐granule inhabitants.     

Regulatory mechanisms of C4b‐binding protein (C4BP)α and β expression in rat hepatocytes by lipopolysaccharide and interleukin‐6

Summary. Background: C4b‐binding protein (C4BP), a multimeric protein structurally composed of α chains (C4BPα) and a β chain (C4BPβ), regulates the anticoagulant activity of protein S (PS). Patients with sepsis have increased levels of plasma C4BP, which appears to be induced by interleukin (IL)‐6. However, it is not fully understood how lipopolysaccharide (LPS) and IL‐6 affect the plasma C4BP antigen level and C4BPα and C4BPβ expression in hepatocytes. Objectives: To assess the effect of LPS and IL‐6 on plasma C4BP, PS–C4BP complex levels, PS activity, and C4BP expression by rat liver in vivo and on C4BP expression by isolated rat hepatocytes in vitro. Results: Plasma C4BP antigen level transiently decreased from 2 to 12 h after LPS (2 mg kg^?1) injection, and then it abruptly increased up to 24 h after LPS injection. Plasma C4BP antigen level increased until 8 h after IL‐6 (10 μg kg^?1) injection, and then gradually decreased up to 24 h after IL‐6 injection. LPS significantly decreased the protein and mRNA expression of both C4BPα and C4BPβ in rat hepatocytes, and this effect was inhibited by NFκB and MEK/ERK inhibitors. IL‐6 mediated increase in C4BPβ expression in rat hepatocytes, which leads to increased plasma PS–C4BP complex level and to decreased plasma PS activity, was inhibited by inhibition of STAT‐3. Conclusion: LPS decreases both C4BPα and C4BPβ expression via the NFκB and MEK/ERK pathways, whereas IL‐6 specifically increases C4BPβ expression via the STAT‐3 pathway, causing an increase in plasma PS–C4BP complex, and thus decreasing the anticoagulant activity of PS.     

Serum paraoxonase‐I activity is unaffected by short‐term administration of simvastatin,bezafibrate, and their combination in type 2 diabetes mellitus

Background The high‐density lipoprotein (HDL)‐associated anti‐oxidative and anti‐inflammatory enzyme, paraoxonase‐I, has been found previously to be lower in type 2 diabetes mellitus. We studied whether statin and fibrate treatment, alone and in combination, affect serum paraoxonase‐I activity in conjunction with changes in HDL cholesterol in diabetic patients. Subjects and methods A placebo‐controlled crossover study was carried out in 14 type 2 diabetic patients to test the effect of 8 weeks of active treatment with simvastatin (40 mg daily), bezafibrate (400 mg daily), and their combination on serum paraoxonase‐I activity, measured as its activity towards arylesterase and paraoxon. Serum paraoxonase‐I activity was also compared between these diabetic patients and 49 non‐diabetic control subjects. Results Serum arylesterase activity was lower in type 2 diabetic patients compared to control subjects (P < 0·001), but the difference in paraoxonase activity was not significant (P = 0·22). Neither arylesterase (P = 0·24) nor paraoxonase activity (P = 0·37) was increased in response to treatment, despite higher HDL cholesterol and apolipoprotein A‐I during combination therapy (P < 0·05 for both). Conclusion Short‐term administration of simvastatin and bezafibrate, even when combined, is ineffective in raising serum paraoxonase‐I activity in type 2 diabetes.     

Effects of variation in the human α2A‐ and α2C‐adrenoceptor genes on cognitive tasks and pain perception

Background: The mechanisms underlying interindividual variability in pain perception and cognitive responses are undefined but highly heritable. α_2C‐ and α_2A‐adrenergic receptors regulate noradrenergic activity and are important mediators of pain perception and analgesia. We hypothesized that common genetic variants in these genes, particularly the ADRA2C 322–325 deletion variant, affect pain perception or cognitive responses. Methods: We studied 73 healthy subjects (37 Caucasians and 36 African–Americans) aged 25.4 ± 4.6 years. Pain response to a cold pressor test was measured using a 10 cm visual analog scale and again on the next day, after three infusions of the selective α₂‐agonist dexmedetomidine. Standardized cognitive tests were administered at baseline and after each infusion. The contribution of ADRA2C deletion genotype, dexmedetomidine concentration, and other covariates to pain perception and cognitive responses was determined using multiple linear regression models. Secondary analysis examined the effects of ADRA2A and other ADRA2C variants on pain perception. Results: ADRA2C Del homozygotes had higher pain scores in response to cold at baseline (6.3 ± 1.8 cm) and after dexmedetomidine (5.6 ± 2.2 cm) than insertion allele carriers (4.6 ± 2.1 cm [baseline] and 3.8 ± 1.9 cm [after dexmedetomidine]; adjusted P‐values = 0.019 and 0.004, respectively). Cognitive responses were unrelated to ADRA2C Ins/Del genotype. None of the other ADRA2A and ADRA2C variants was significantly related to cold pain sensitivity before dexmedetomidine; after dexmedetomidine, ADRA2A rs1800038 was marginally associated (P = 0.03). Conclusion: The common ADRA2C del322–325 variant affected pain perception before and after dexmedetomidine but did not affect other cognitive responses, suggesting that it contributes to interindividual variability in pain perception.