Differential Regulation by Butyrate and Dibutyryl Cyclic AMP of δ-Opioid, α2-Adrenergic, and Muscarinic Cholinergic Receptors in NCB-20 Cells

Long-term treatment of NCB-20 cells with sodium butyrate resulted in a marked increase in the specific binding of [3H]D-Ala2,D-Leu5 enkephalin. This increase was concentration and time dependent, with an EC50 of about 480 microM and a maximal effect detected after 3-day treatment. At saturating concentration of butyrate (1 mM) the increase was three- to fourfold of the untreated control. Scatchard analysis revealed that the butyrate effect was due to an increase in the density of the opioid receptor binding sites. Butyrate also induced a smaller (about twofold) increase in the density of muscarinic cholinergic receptor binding assessed by using [3H]quinuclidinyl benzilate, whereas alpha 2-adrenergic receptor binding assessed by using [3H]clonidine was not significantly affected. The butyrate-induced opioid receptor binding could be totally abolished by the presence of cycloheximide, suggesting that the butyrate effect involves synthesis of the receptor protein. Butyrate treatment did not affect basal and prostaglandin E1-stimulated cyclic AMP levels but caused a three- to fourfold decrease in the IC50 of D-Ala2,D-Leu5 enkephalin for attenuating these cyclic AMP levels and approximately 25% increase in the maximal extent of attenuation. In contrast to the butyrate effect, long-term treatment of NCB-20 cells with 1 mM dibutyryl cyclic AMP induced an 80% decrease in the opioid and alpha 2-adrenergic receptor bindings and a 57% loss of muscarinic cholinergic receptor binding. This down-regulation of muscarinic cholinergic receptor binding sites was associated with a 35% decrease of carbachol-induced phosphoinositide breakdown, whereas the receptor up-regulation induced by butyrate was found to increase the carbachol response by about threefold. The differential regulation by butyrate and dibutyryl cyclic AMP suggests that the butyrate effect is mediated by a mechanism independent of intracellular cyclic AMP. The induction by butyrate of opioid-receptors and muscarinic cholinergic receptors in NCB-20 cells may provide a useful system for studying the regulation of gene expression of these receptor proteins.     

Substrates for protein kinase C in a cell free preparation of rat aorta smooth muscles

Protein phosphorylation has been studied in a cell free system of rat aorta smooth muscles. Addition of Ca2+ caused phosphorylation of several proteins. The addition of phosphatidylserine or calmodulin together with Ca2+ further increased the phosphorylation of proteins with apparent molecular weights of 20 and 92.5 kilodaltons. The activators of protein kinase C, 12-0-tetradecanoylphorbol-13-acetate and 1,2-diolein, increased phosphorylation of the protein bands of similar molecular weight to those increased by phosphatidylserine in the presence of Ca2+, whereas the biologically inactive phorbol ester, 4 alpha-phorbol-12,13 didecanoate (4 alpha PDD) failed to change the pattern of protein phosphorylation. These results show that proteins present in smooth muscle of rat aorta with molecular weights of 20 and 92.5 kilodaltons are substrates for protein kinase C.     

The Species and Origin of Shark Fins in Taiwan’s Fishing Ports,Markets, and Customs Detention: A DNA Barcoding Analysis

The increasing consumption of shark products, along with the shark’s fishing vulnerabilities, has led to the decrease in certain shark populations. In this study we used a DNA barcoding method to identify the species of shark landings at fishing ports, shark fin products in retail stores, and shark fins detained by Taiwan customs. In total we identified 23, 24, and 14 species from 231 fishing landings, 316 fin products, and 113 detained shark fins, respectively. All the three sample sources were dominated by Prionace glauca, which accounted for more than 30% of the collected samples. Over 60% of the species identified in the fin products also appeared in the port landings, suggesting the domestic-dominance of shark fin products in Taiwan. However, international trade also contributes a certain proportion of the fin product markets, as four species identified from the shark fin products are not found in Taiwan’s waters, and some domestic-available species were also found in the customs-detained sample. In addition to the species identification, we also found geographical differentiation in the cox1 gene of the common thresher sharks (Alopias vulpinus), the pelagic thresher shark (A. pelagicus), the smooth hammerhead shark (Sphyrna zygaena), and the scalloped hammerhead shark (S. lewini). This result might allow fishing authorities to more effectively trace the origins as well as enforce the management and conservation of these sharks.     

Neuromuscular abnormality and autonomic dysfunction in patients with cerebrotendinous xanthomatosis

Background  

Cerebrotendinous xanthomatosis (CTX) is a rare lipid-storage disease. Neuromuscular abnormality and autonomic system (ANS) dysfuction in CTX are rarely examined in large-scale studies in the literature. We studied the peripheral nervous system, myopathology, and autonomic system of four CTX patients and performed a literature review of the reported CTX patients with peripheral neuropathy.     

Behavioral effects of congenital ventromedial prefrontal cortex malformation

Background  

A detailed behavioral profile associated with focal congenital malformation of the ventromedial prefrontal cortex (vmPFC) has not been reported previously. Here we describe a 14 year-old boy, B.W., with neurological and psychiatric sequelae stemming from focal cortical malformation of the left vmPFC.     

Matrix metalloproteinase-9 inhibition or deletion attenuates portal hypertension in rodents

Liver cirrhosis and portal hypertension are accompanied by hyperdynamic circulation, angiogenesis and portosystemic collaterals. Matrix metalloproteinases (MMPs) participate in fibrogenesis and angiogenesis, however, whether they can be targeted in cirrhosis treatment is unclear. Therefore, we performed three series of experiments to investigate this issue. Liver cirrhosis was induced by common bile duct ligation (BDL) in Sprague-Dawley rats. Sham-operated rats served as controls. Rats were randomly allocated to receive vehicle, minocycline (a nonselective MMP inhibitor) or SB-3CT (MMP-2 and −9 inhibitor) for 28 days in the first and second series, respectively. MMP-9 knockout mice were used in the third series. The results showed that minocycline ameliorated portal hypertension, hemodynamic abnormalities, reduced collateral shunting, mesenteric vascular density, plasma VEGF level and alleviated liver fibrosis. SB-3CT attenuated portal hypertension, hemodynamic derangements, reduced shunting, mesenteric vascular density, mesenteric VEGF protein expression, and liver fibrosis. Knockout BDL mice had significantly alleviated portal hypertension, liver fibrosis, liver α-SMA and mesenteric eNOS protein expressions compared to wild-type BDL mice. Liver SMAD2 phosphorylation was down-regulated in all series with MMP inhibition or knock-out. In conclusion, MMP-9 inhibition or deletion ameliorated the severity of cirrhosis, portal hypertension, and associated derangements. MMP-9 may be targeted in the treatment of liver cirrhosis.     

Inference of Cross-Level Interaction between Genes and Contextual Factors in a Matched Case-Control Metabolic Syndrome Study: A Bayesian Approach

Genes, environment, and the interaction between them are each known to play an important role in the risk for developing complex diseases such as metabolic syndrome. For environmental factors, most studies focused on the measurements observed at the individual level, and therefore can only consider the gene-environment interaction at the same individual scale. Indeed the group-level (called contextual) environmental variables, such as community factors and the degree of local area development, may modify the genetic effect as well. To examine such cross-level interaction between genes and contextual factors, a flexible statistical model quantifying the variability of the genetic effects across different categories of the contextual variable is in need. With a Bayesian generalized linear mixed-effects model with an unconditional likelihood, we investigate whether the individual genetic effect is modified by the group-level residential environment factor in a matched case-control metabolic syndrome study. Such cross-level interaction is evaluated by examining the heterogeneity in allelic effects under various contextual categories, based on posterior samples from Markov chain Monte Carlo methods. The Bayesian analysis indicates that the effect of rs1801282 on metabolic syndrome development is modified by the contextual environmental factor. That is, even among individuals with the same genetic component of PPARG_Pro12Ala, living in a residential area with low availability of exercise facilities may result in higher risk. The modification of the group-level environment factors on the individual genetic attributes can be essential, and this Bayesian model is able to provide a quantitative assessment for such cross-level interaction. The Bayesian inference based on the full likelihood is flexible with any phenotype, and easy to implement computationally. This model has a wide applicability and may help unravel the complexity in development of complex diseases.     

Regulation of autophagy by E3 ubiquitin ligase RNF216 through BECN1 ubiquitination

Autophagy is an evolutionarily conserved biological process involved in an array of physiological and pathological events. Without proper control, autophagy contributes to various disorders, including cancer and autoimmune and inflammatory diseases. It is therefore of vital importance that autophagy is under careful balance. Thus, additional regulators undoubtedly deepen our understanding of the working network, and provide potential therapeutic targets for disorders. In this study, we found that RNF216 (ring finger protein 216), an E3 ubiquitin ligase, strongly inhibits autophagy in macrophages. Further exploration demonstrates that RNF216 interacts with BECN1, a key regulator in autophagy, and leads to ubiquitination of BECN1, thereby contributing to BECN1 degradation. RNF216 was involved in the ubiquitination of lysine 48 of BECN1 through direct interaction with the triad (2 RING fingers and a DRIL [double RING finger linked]) domain. We further showed that inhibition of autophagy through overexpression of RNF216 in alveolar macrophages promotes Listeria monocytogenes growth and distribution, while knockdown of RNF216 significantly inhibited these outcomes. These effects were confirmed in a mouse model of L. monocytogenes infection, suggesting that manipulating RNF216 expression could be a therapeutic approach. Thus, our study identifies a novel negative regulator of autophagy and suggests that RNF216 may be a target for treatment of inflammatory diseases.