The molecular mechanism of fibroblast growth factor 21-inhibited leptin expression in adipocytes / 生理学报

The present study was aimed to clarify the signaling molecular mechanism by which fibroblast growth factor 21 (FGF21) regulates leptin gene expression in adipocytes. Differentiated 3T3-F442A adipocytes were used as study object. The mRNA expression level of leptin was detected by fluorescence quantitative RT-PCR. The phosphorylation levels of proteins of signal transduction pathways were detected by Western blot. The results showed that FGF21 significantly down-regulated the mRNA expression level of leptin in adipocytes, and FGF21 receptor inhibitor BGJ-398 could completely block this effect. FGF21 up-regulated the phosphorylation levels of ERK1/2 and AMPK in adipocytes. Either ERK1/2 inhibitor SCH772984 or AMPK inhibitor Compound C could partially block the inhibitory effect of FGF21, and the combined application of these two inhibitors completely blocked the effect of FGF21. Neither PI3K inhibitor LY294002 nor Akt inhibitor AZD5363 affected the inhibitory effect of FGF21 on leptin gene expression. These results suggest that FGF21 may inhibit leptin gene expression by activating ERK1/2 and AMPK signaling pathways in adipocytes.

Thiol/disulfide status regulates the activity of thiol-containing kinases related to energy homeostasis in rat kidney

ABSTRACT Considering that thiol-containing enzymes like kinases are critical for several metabolic pathways and energy homeostasis, we investigated the effects of cystine dimethyl ester and/or cysteamine administration on kinases crucial for energy metabolism in the kidney of Wistar rats. Animals were injected twice a day with 1.6 µmol/g body weight cystine dimethyl ester and/or 0.26 µmol/g body weight cysteamine from the 16th to the 20th postpartum day and euthanized after 12 hours. Pyruvate kinase, adenylate kinase, creatine kinase activities and thiol/disulfide ratio were determined. Cystine dimethyl ester administration reduced thiol/disulfide ratio and inhibited the kinases activities. Cysteamine administration increased the thiol/disulfide ratio and co-administration with cystine dimethyl ester prevented the inhibition of the enzymes. Regression between the thiol/disulfide ratio, and the kinases activities were significant. These results suggest that redox status may regulate energy metabolism in the rat kidney. If thiol-containing enzymes inhibition and oxidative stress occur in patients with cystinosis, it is possible that lysosomal cystine depletion may not be the only beneficial effect of cysteamine administration, but also its antioxidant and thiol-protector effect.

Anti-interleukin-33 Reduces Ovalbumin-Induced Nephrotoxicity and Expression of Kidney Injury Molecule-1 / 대한배뇨장애요실금학회지

PURPOSE: To evaluate the effect of anti-interleukin-33 (anti-IL-33) on a mouse model of ovalbumin (OVA)-induced acute kidney injury (AKI). METHODS: Twenty-four female BALB/c mice were assigned to 4 groups: group A (control, n=6) was administered sterile saline intraperitoneally (i.p.) and intranasally (i.n.); group B (allergic, n=6) was administered i.p./i.n. OVA challenge; group C (null treatment, n=6) was administered control IgG i.p. before OVA challenge; and group D (anti-IL-33, n=6) was pretreated with 3.6 µg of anti-IL-33 i.p. before every OVA challenge. The following were evaluated after sacrifice: serum blood urea nitrogen and creatinine levels, Kidney injury molecule-1 gene (Kim-1) and protein (KIM-1) expression in renal parenchyma, and expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), phosphorylated endothelial NOS (p-eNOS), and phosphorylated AMP kinase (p-AMPK) proteins in renal parenchyma. RESULTS: After OVA injection and intranasal challenge, mice in groups B and C showed significant increases in the expression of Kim-1 at both the mRNA and protein levels. After anti-IL-33 treatment, mice in group D showed significant Kim-1 down-regulation at the mRNA and protein levels. Group D also showed significantly lower COX-2 protein expression, marginally lesser iNOS expression than groups B and C, and p-eNOS and p-AMPK expression at baseline levels. CONCLUSIONS: Kim-1 could be a useful marker for detecting early-stage renal injury in mouse models of OVA-induced AKI. Further, anti-IL-33 might have beneficial effects on these mouse models.

Visfatin Protects Rat Pancreatic β-cells against IFN-γ-Induced Apoptosis through AMPK and ERK1/2 Signaling Pathways / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Interferon-γ (IFN-γ) plays an important role in apoptosis and was shown to increase the risk of diabetes. Visfatin, an adipokine, has anti-diabetic, anti-tumor, and regulating inflammatory properties. In this study we investigated the effect of visfatin on IFN-γ-induced apoptosis in rat pancreatic β-cells.</p><p><b>METHODS</b>The RINm5F (rat insulinoma cell line) cells exposed to IFN-γ were treated with or without visfatin. The viability and apoptosis of the cells were assessed by using MTT and flow cytometry. The expressions of mRNA and protein were detected by using real-time PCR and western blot analysis.</p><p><b>RESULTS</b>The exposure of RINm5F cells to IFN-γ for 48 h led to increased apoptosis percentage of the cells. Visfatin pretreatment significantly increased the cell viability and reduced the cell apoptosis induced by IFN-γ. IFN-γ-induced increase in expression of p53 mRNA and cytochrome c protein, decrease in mRNA and protein levels of anti-apoptotic protein Bcl-2 were attenuated by visfatin pretreatment. Visfatin also increased AMPK and ERK1/2 phosphorylation and the anti-apoptotic action of visfatin was attenuated by the AMPK and ERK1/2 inhibitor.</p><p><b>CONCLUSION</b>These results suggested that visfatin protected pancreatic islet cells against IFN-γ-induced apoptosis via mitochondria-dependent apoptotic pathway. The anti-apoptotic action of visfatin is mediated by activation of AMPK and ERK1/2 signaling molecules.</p>

Modified Si-Miao-San inhibits inflammation and promotes glucose disposal in adipocytes through regulation of AMP-kinase / 中国天然药物

Modified Si-Miao-San (mSMS) is composed of Rhizoma Coptidis, Cortex Phellodendri, Rhizoma Coptidis Semen Coicis and Atractylodes Rhizome. The prescription is used for the management of diabetes and insulin resistance in the clinic. This study aims to investigate its regulation of glucose disposal in adipocytes. Differentiated 3T3-L1 adipocytes were stimulated with conditioned medium derived from activated macrophages to induce insulin resistance and observed the effects of Mac-CM on insulin-mediated glucose uptake along the insulin receptor substrate-1/PI3K/Akt signaling pathway. Moreover, its regulation of AMPK phosphorylation was also investigated. mSMS enhanced AMPK phosphorylation and promoted basal glucose uptake in adipocytes; mSMS inhibited NF-κB activation by reducing P65 phosphorylation and improved insulin-stimulated IRS-1 tyrosine and Akt phosphorylation, leading to the restoration of insulin-mediated glucose uptake when cells were exposed to inflammatory stimulation. These beneficial effects were diminished in the presence of the AMPK inhibitor compound C. mSMS positively regulated AMPK activity, and this action contributed to improving insulin PI3K signaling by the beneficial regulation of IRS-1 function through inhibition of inflammation in adipocytes.

Arctiin inhibits adipogenesis in 3T3-L1 cells and decreases adiposity and body weight in mice fed a high-fat diet

BACKGROUND/OBJECTIVES: The purpose of this study was to examine the effects and associated mechanisms of arctiin, a lignan compound found in burdock, on adipogenesis in 3T3-L1 cells. Also, the effects of arctiin supplementation in obese mice fed a high-fat diet on adiposity were examined. MATERIALS/METHODS: 3T3-L1 cells were treated with arctiin (12.5 to 100 microM) during differentiation for 8 days. The accumulation of lipid droplets was determined by Oil Red O staining and intracellular triglyceride contents. The expressions of genes related to adipogenesis were measured by real-time RT-PCR and Western blot analyses. For in vivo study, C57BL/6J mice were first fed either a control diet (CON) or high-fat diet (HF) to induce obesity, and then fed CON, HF, or HF with 500 mg/kg BW arctiin (HF + AC) for four weeks. RESULTS: Arctiin treatment to 3T3-L1 pre-adipocytes markedly decreased adipogenesis in a dose-dependent manner. The arctiin treatment significantly decreased the protein levels of the key adipogenic regulators PPARgamma and C/EBPalpha, and also significantly inhibited the expression of SREBP-1c, fatty acid synthase, fatty acid-binding protein and lipoprotein lipase. Also, arctiin greatly increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target phosphorylated-acetyl CoA carboxylase. Furthermore, administration of arctiin significantly decreased the body weight in obese mice fed with the high-fat diet. The epididymal, perirenal or total visceral adipose tissue weights of mice were all significantly lower in the HF + AC than in the HF. Arctiin administration also decreased the sizes of lipid droplets in the epididymal adipose tissue. CONCLUSIONS: Arctiin inhibited adipogenesis in 3T3-L1 adipocytes through the inhibition of PPARgamma and C/EBPalpha and the activation of AMPK signaling pathways. These findings suggest that arctiin has a potential benefit in preventing obesity.

Simvastatin inhibits activation of hepatic stellate cells and promotes activation of adenosine monophosphate-activated protein kinase / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the underlying molecular mechanism of the cholesterol-blocking drug, simvastatin, in treating nonalcoholic fatty liver fibrosis.</p><p><b>METHOD</b>A rat model of nonalcoholic fatty liver fibrosis was established by feeding Wistar rats a fat-rich diet. After treatment with simvastatin (4 mg/kg/day), liver histological specimens were stained with hematoxylin-eosin and Masson's trichrome for microscopic analysis. Expression of adenosine monophosphate-activated protein kinase-alpha (AMPKa) was evaluated by reverse transcription-polymerase chain reaction (RT-PCR; for mRNA) and Western blotting (protein). The levels of serum total cholesterol (TC), triglycerides (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-alpha (TNFa) were measured by standard biochemical assays. The human hepatic stellate cell line, LX-2 (quiescent or activated), was treated with transforming growth factor-beta 1 (TGF-b1) alone, simvastatin alone, or TGF-b1 + simvastatin. RT-PCR and Western blotting were used to determine changes in AMPKa mRNA and protein expression, respectively.</p><p><b>RESULTS</b>In the rat model of nonalcoholic fatty liver fibrosis, the extent of pathological changes in hepatic tissues correlated with severity of disease progression. The levels of serum TC, TG, ALT, AST and TNFa were increased significantly in model rats (vs. healthy controls; all, P less than 0.01). AMPKa mRNA expression and activity was significantly decreased in model rats (vs. healthy controls; P less than 0.01 and P less than 0.05, respectively). Simvastatin, treatment significantly improved all of these parameters in model rats (vs. untreated model rats; all, P less than 0.05). In vitro simvastatin treatment of human HSCs significantly increased AMPKa activity (quiescent LX-2: 0.93+/-0.10 vs. 0.72+/-0.09, activated LX-2: 0.72+/-0.10 vs. 0.54+/-0.10, q=7.00, 6.00; all, P less than 0.01), decreased a-smooth muscle actin expression (mRNA: 0.30+/-0.02 vs. 0.36+/-0.02, protein: 0.30+/-0.03 vs. 0.38+/-0.02, q=11.245, 11.216; all, P less than 0.01), and decreased collagen I expression (mRNA: 0.30+/-0.03 vs. 0.37+/-0.03, protein: 0.25+/-0.03 vs. 0.33+/-0.03, q=8.791, 11.163; all, P less than 0.01).</p><p><b>CONCLUSION</b>Simvastatin may improve nonalcoholic fatty liver fibrosis by inducing AMPK phosphorylation.</p>

Anti-obesity effects of Chang-Chul-Eui-Ee-In-Tang see text in female rats with diet-induced obesity / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Chang-Chul-Eui-Ee-In-Tang ([see text], CCEET), modififi ed CCEET (MCCEET), and Semen Coicis (SC, a major component of CCEET) on energy and glucose homeostasis. The possible mechanism of action of CCEET was also determined.</p><p><b>METHODS</b>A total of 100 Sprague Dawley female rats were randomly assigned to 5 groups, with 20 in each group. Rats in 4 groups were fed with a high fat diet supplementation (2 g/kg body weight), and water extracts of CCEET, MCCEET, SC, and cellulose (negative control), respectively. The last group was fed with a low-fat diet as a positive control.</p><p><b>RESULTS</b>CCEET and MCCEET decreased body weight and body fat (mesenteric and retroperitoneal fat) more than SC. This decrease was due to decreased energy intake and increased energy expenditure and fat oxidation. The improvement in energy homeostasis was associated with the enhancement of the hypothalamic leptin signalling pathway involving potentiating the phosphorylation of the signal transducer and activator of transcription-3, as well as attenuating the phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK). Both CCEET and MCCEET improved glucose tolerance without changing serum insulin levels during an oral glucose tolerance test but MCCEET had a better effect than CCEET.</p><p><b>CONCLUSIONS</b>Both CCEET and MCCEET safely exerted anti-obesity effects by enhancing energy balance in female rats with diet-induced obesity; MCCEET showed a better effect on glucose homeostasis.</p>

Atorvastatin protects swine bone marrow mesenchymal stem cells from apoptosis through AMPK but not PI3K/Akt pathway / 中华心血管病杂志

<p><b>OBJECTIVE</b>The effect of mesenchymal stem cells (MSCs) transplantation is poor because of the harsh environment post infarction. Our previous studies have proven that Statins could enhance the implanted bone marrow MSCs survival, but the exact mechanism remained to be clarified. We hypothesized that atorvastatin (Ator) could protect MSCs from hypoxia and serum-free (H/SF) induced apoptosis and investigated the potential mechanisms.</p><p><b>METHODS</b>Chinese mini-swine's bone marrow derived MSCs were cultured in vitro and exposed to hypoxia and H/SF, Ator of various concentrations (0.001 - 10 µmol/L), AMPK inhibitor-compound C (CC), PI3K inhibitor-LY294002 (LY), Ator + CC and Ator + LY. Cell apoptosis was assessed using Annexin V/Prospidine Iodine kit by flow cytometry. Phosphorylation of AMPK, Akt, endothelial nitric oxide synthase (eNOS) level and phosphorylation were tested with Western blot. Real Time-PCR was performed to analyze the gene expression of AMPK, Akt and eNOS.</p><p><b>RESULTS</b>MSCs apoptosis in Ator (0.01 - 10 µmol/L) treated H/SF groups was significantly reduced compared with H/SF group (1.94% - 6.10% vs. 10.94%, P < 0.01 or 0.05). Apoptosis was higher in Ator + CC group than in 1 µmol/L Ator group (4.94% ± 0.98% vs. 2.59% ± 0.84%, P < 0.01) and similar between Ator + LY and 1 µmol/L Ator group (2.02% ± 0.45% vs. 2.59% ± 0.84%, P > 0.05). The gene expressions of AMPK, Akt and eNOS were significantly upregulated in atorvastatin treated groups. Meanwhile, phosphorylation of AMPK and eNOS increased in MSCs treated with atorvastatin (P < 0.01 or 0.05). Phosphorylation of eNOS significantly correlated with AMPK phosphorylation (r = 0.599, P = 0.004), but not with Akt phosphorylation (P = 0.263).</p><p><b>CONCLUSIONS</b>Atorvastatin can protect MSCs from H/SF induced apoptosis through AMPK pathway, which resulting in activation of eNOS.</p>

Expression, purification and enzymatic characterization of adenylate kinase of Thermus thermophilus HB27 in Escherichia coli / 南方医科大学学报

<p><b>OBJECTIVE</b>To clone the gene encoding adenylate kinase of Thermus thermophilus HB27, an extremely thermophilic bacterium, express the protein in Escherichia coil and study the enzymatic characterization.</p><p><b>METHODS</b>The DNA fragment encoding adenylate kinase was obtained by PCR from the total DNA of Thermus thermophilus HB27 and cloned into the vector pET-28a. The recombinant plasmid was identified by PCR, restriction endonuclease digestion and sequence analysis. Enzymatic characterization of the expressed protein was carried out using spectrophotometric assays.</p><p><b>RESULTS</b>The gene coding for adenylate kinase from Thermus thermophilus HB27 was cloned and the protein was overexpressed in Escherichia coli BL21(DE3). The optimum reactive pH and temperature for the enzyme were 8.5 and 90 degrees celsius;, respectively. The Km of the recombinant adenylate kinase for ADP was 68.6 micromol/L, with an V(max)ADP of 0.294 mmol/(L.min). Under the condition of environmental temperature at 70, 80, 90, or 100 degrees celsius; for 7 h, the recombinant adenylate kinase still retained the enzymatic activity with high thermostability. AP5A, a specific adenylate kinase inhibitor, inhibited the enzymatic activity of the protein by 70% at the concentration of 2.0 mmol/L, with a Ki value of 46.39 micromol/L for ADP.</p><p><b>CONCLUSION</b>The gene coding for adenylate kinase of Thermus thermophilus HB27 has been successfully cloned and expressed in Escherichia coil, which provides the basis for potential use of the highly thermostable recombinant HB27 adenylate kinase.</p>

Reticular dysgenesis: a very rare and fatal immunodeficiency disease

Human severe combined immunodeficiency [SCID] represents a group of rare, often fatal, congenital disorders characterized by little or no immune response. Reticular dysgenesis [RD] is the most severe form of inborn SCID. Until recently, its genetic basis was unknown. It is only in 2008, that a gene defect has been described. We present here, a unique hematological phenotype of RD with a dramatic clinical course. The paucity of such cases in the literature, merits this report

Molecular cloning of adenylate kinase from the human filarial parasite Onchocerca volvulus

Adenylate kinases [ADK] are ubiquitous enzymes that contribute to the homeostasis of adenine nucleotides in living cells. In this study, the cloning of a cDNA encoding an adenylate kinase from the filaria Onchocerca volvulus has been described. Using PCR technique, a 281 bp cDNA fragment encoding part of an adenylate kinase was isolated from an O. volvulus cDNA library. Use of this fragment as a probe allowed the isolation of a larger cDNA clone through the searching the GenBank expressed sequence tag database. The full-length cDNA encodes 236 amino acid residues with a predicted molecular mass of 26.177 kDa. The deduced amino acid sequence exhibited 80% identity to the homologous adenylate kinase identified from Caenorhabditis elegans. Domain analysis of the resulting protein sequence was found to contain "adenylate kinase signature" motif which is highly conserved in all known ADKs. Multiple alignments showed that the N-terminal is well conserved, whereas the C-terminal is the most variable region

Secretion of adenylate kinase 1 is required for extracellular ATP synthesis in C2C12 myotubes

Extracellular ATP (exATP) has been known to be a critical ligand regulating skeletal muscle differentiation and contractibility. ExATP synthesis was greatly increased with the high level of adenylate kinase 1 (AK1) and ATP synthase beta during C2C12 myogenesis. The exATP synthesis was abolished by the knock-down of AK1 but not by that of ATP synthase beta in C2C12 myotubes, suggesting that AK1 is required for exATP synthesis in myotubes. However, membrane-bound AK1beta was not involved in exATP synthesis because its expression level was decreased during myogenesis in spite of its localization in the lipid rafts that contain various kinds of receptors and mediate cell signal transduction, cell migration, and differentiation. Interestingly, cytoplasmic AK1 was secreted from C2C12 myotubes but not from C2C12 myoblasts. Taken together all these data, we can conclude that AK1 secretion is required for the exATP generation in myotubes.

The role of AMP kinase in diabetes.

Type 2 diabetes is characterized by abnormal metabolism of glucose and fat, due in part to resistance to the actions of insulin in peripheral tissues. If untreated it leads to several complications such as blindness, kidney failure, neuropathy and amputations. The benefit of exercise in diabetic patients is well known and recent research indicates that AMP activated protein kinase (AMPK) plays a major role in this exercise related effect. AMPK is considered as a master switch regulating glucose and lipid metabolism. The AMPK is an enzyme that works as a fuel gauge, being activated in conditions of high energy phosphate depletion. AMPK is also activated robustly by skeletal muscle contraction and myocardial ischaemia, and is involved in the stimulation of glucose transport and fatty acid oxidation produced by these stimuli. In liver, activation of AMPK results in enhanced fatty acid oxidation and decreased production of glucose, cholesterol, and triglycerides. The two leading diabetic drugs namely, metformin and rosiglitazone, show their metabolic effects partially through AMPK. These data, along with evidence from studies showing that chemical activation of AMPK in vivo with 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) improves blood glucose concentrations and lipid profiles, make this enzyme an attractive pharmacological target for the treatment of type 2 diabetes and other metabolic disorders.

Investigation of the Growth Rate Change in Recombinant BCG which was cloned Mycobacterium tuberculosis Adenylate Kinase Mutation Gene or Human Muscle-type Adenylate Kinase Synthetic Gene / 결핵및호흡기질환

BACKGROUND: Normal cell proliferation and viability is strongly depends on the availability of metabolic energy and the maintenance of the appropriate adenylate-nucleotide pools. Hypothetically, changes in adenylate kinase (AK) expression could therefore be associated with adaptation to altered growth characteristics or inversely altered growth characteristics of proliferating cells could drive the changes in the metabolic profile. This study investigated whether the expression of either AK1 or a Mycobacterium tuberculosis adenylate kinase mutant which has the same catalytic activity of AK1 could affect the growth rate of slow-growing BCG. METHOD: Recombinant BCGs, which were cloned the human muscle-type adenylate kinase synthetic gene (AK1) and adenylate kinase mutation gene (AKmtDM) of Mycobacterium tuberculosis into the Mycobacterium/E.coli expression vectors, were constructed. Recombinant BCGs and wild-type BCG were cultured in 7H9 media and the optical density at 600nm was measured at intervals of 2-3 days. RESULT: There wasn't the growth rate change induced by AK1 or AKmtDM expression in recombinant BCGs. CONCLUSION: The expression of AK1 or Mycobacterium tuberculosis adenylate kinase mutant in BCG does not affect the growth rate of BCG.

Protective Efficacy of Recombinant Proteins Adenylate Kinase, Nucleoside Diphosphate Kinase, and Heat-Shock Protein 70 against Mycobacterium tuberculosis Infection in Mice / 결핵및호흡기질환

BACKGROUND: Priming and boosting vaccination strategy has been widely explored for new vaccine development against tuberculosis. As an effort to identify other vaccine candidates, this study was initiated to evaluate protective efficacy of adenylate kinase (AK), nucleoside diphosphate kinase (NdK), and heat shock protein 70 (Hsp70) of Mycobacterium tuberculosis. METHOD: M. tuberculosis genes encoding AK, NdK, and Hsp70 proteins were amplified by PCR and cloned into E. coli expression vector, pQE30. Recombinant AK, NdK, and Hsp70 was purified through Ni-NTA resin. To evaluate immune responses, we performed enzyme-linked immunosorbent assay (ELISA) for IgG isotype and IFN-gamma after mice were immunized subcutaneously with recombinant proteins delivered in dimethyl dioctadecylammonium bromide (DDA). Immunized- and control groups were challenged by aerosol with M. tuberculosis. The spleens and lungs of mice were removed aseptically and cultured for CFU of M. tuberculosis. RESULT: Vaccination with recombinant proteins AK, NdK, and Hsp70 delivered in DDA elicited significant level of antibody and IFN-gamma responses to corresponding antigens but no protective immunity comparable to that achieved with Mycobacterium bovis BCG. CONCLUSION: Recombinant proteins AK, NdK, and Hsp70 do not effectively control growth of M. tuberculosis in mice when immunized with DDA as an adjuvant.

Serological Kinetics of Adenylate Kinase 3 in Rat Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: Currently used serological markers for the diagnosis of acute myocardial infarction differ in appearance time and specificity for myocardial infarction, allowing no ideal single serological marker for myocardial infarction. Adenylate kinase (AK) is a ubiquitous enzyme which contributes to the homeostasis of the cellular adenine nucleotides pool. AK is abundant in the myocardium, and we postulated that AK3 could be used as a biochemical marker for the diagnosis of acute myocardial infarction (AMI). MATERALS AND METHODS: We constructed an AMI rat model with ligation of the anterior descending artery. We measured the concentration of serum AK3 in the AMI rat model by enhanced chemiluminescence (ECL) sandwich ELISA using monoclonal antibodies against recombinant AK3. RESULTS: The serum AK3 level started to increase in 3 hours and reached a peak at 6 hours after ligation of the rat coronary artery. The significant elevation of AK3 was retained for 2 days (p<0.05). CONCLUSION: AK3 is a useful serological marker for acute myocardial infarction in the rat.

Matabolismo energético durante el desarrollo de la placenta en ratas: efecto de la desnutrición materna crónica / Energy metabolism during placental development in rats-effect of chronic maternal malnutrition

Se estudió el efecto de la desnutricion crónica materna en el metabolismo enerético durante el desarrollo de la placenta en ratas y su relación con el crecimiento fetal. Ratas hembras vírgines de la cepa Wistar se sosmetieron a la restricción de una dieta con 25% de caseína, desde la pubertad y durante la preñez. Los resultados revelaron que la desnutrición materna disminuye significativamente la actividad de adenilato kinasa expresada pr gramo de DNA, y aumenta significativamente el contenido de adenina nucleótidios (ATP y ADP) en la placenta, cerca del término de la preñez. Se postula que el aumento significativo de la carga energética (ATP + 1/2 ADP:/ ATP + AMP) de la placenta de ratas desnutridas, es el resultado de una inhibición de los sistemas que utilizan ATP para procesos de síntesis de macromoléculas y transporte activo de sustratos en las últimas etapas de la gestación. Ello coincide con la significativa disminución del crecimiento fetal en esa etapa

Alteraçöes enzimáticas eritrocitárias na hemofilia A / Erythrocyte enzymatic changes in hemophilia A

Cinco quinases eritrocitárias foram estudadas em pacientes portadores de hemofilia A; foi encontrado um aumento das atividades da fosfogliceratoquinase e da adenilatoquinase. Este achado sugere que há alteraçöes metabólicas eritrocitárias na hemofilia