Sheila Leone

Dual acting anti-inflammatory drugs

Drugs able to inhibit both cyclooxygenases (COX-1 and COX-2) and 5-lipoxygenase (5-LOX) (dual acting anti-inflammatory drugs) have been designed in order to obtain compounds that retain the activity of classical nonsteroidal anti-inflammatory drugs (NSAIDs) while avoiding their main drawbacks. The classical NSAIDs display their anti-inflammatory action mainly through inhibition of COX and one of their main drawbacks is the curtailed production of gastroprotective prostaglandins (PGs) being associated with the concurrent increased production of the gastro-damaging and bronchoconstrictive leukotrienes (LTs). Leukotrienes and cysteinyl-leukotrienes are moreover pro-inflammatory and increase microvascular permeability. One of the leukotrienes (LTB(4)) is the most potent chemotactic agent and it induces chemotaxis of eosinophils, neutrophils and monocytes in the inflamed tissue, increases superoxide generation and proinflammatory cytokines production. It is further advantageous for a drug to have both COX and 5-LOX inhibiting activities because prostaglandins enhance leukotriene-mediated inflammation. Various structural families of dual inhibitors have been designed and several compounds are currently undergoing clinical development. In the post-COX-2 selective inhibitors era, these dual acting inhibitors may turn out to be promising new drugs to treat inflammatory diseases and possibly other diseases. Indeed, both COX-2 and 5-LOX are also involved in the development and progression of several types of cancer; in these conditions, selective inhibition of COX-2 alone may lead to a shunt of arachidonic acid metabolism towards the leukotriene pathway, and therefore the blockade of both COX-2 and 5-LOX may produce a better anticancer response. In addition, the dual inhibition of both COX and 5-LOX is neuroprotective by suppressing toxic actions of reactive microglia and macrophages, that are increased in aging brain and in age-related degenerative conditions, particularly Alzheimers and Parkinsons diseases. Finally, the blockade of 5-LOX does not impair the synthesis of lipoxins (LXs), which are mainly produced by further lipoxygenation of 15-HPETE, and which have potent anti-inflammatory properties and can be considered as stop-signal mediators. Leukocyte 15-LOX and platelet 12-LOX by intercellular mechanism via leukocyte/platelet cell-cell interaction convert 15-HPETE into lipoxins.

Similarities and differences between chronic migraine and episodic migraine

Objective.—To quantify and characterize the similarities and the differences between chronic migraine (CM) patients with medication overuse and episodic migraine (EM) patients with only occasional analgesic use.

Effects of vaspin, chemerin and omentin-1 on feeding behavior and hypothalamic peptide gene expression in the rat.

Visceral adipose tissue-derived serpin (vaspin) improves glucose tolerance and insulin sensitivity in diet-induced obese mice. Chemerin may increase insulin sensitivity in adipose tissue and seems to be associated with several key aspects of metabolic syndrome. Decreased levels of omentin-1 are associated with increasing obesity and insulin resistance. Our study aimed to investigate the effects of vaspin, chemerin and omentin-1 acute administration on feeding and hypothalamic gene expression of peptides which play a key role in feeding regulation. 35 rats were injected into the arcuate nucleus (ARC) of the hypothalamus with either saline (n=8), vaspin (1μg/kg; n=9), chemerin (8μg/kg; n=9), or omentin-1 (8μg/kg; n=9). Food intake in the following 24h was recorded, thereafter rats were sacrificed. Total RNA was extracted from hypothalami and reverse transcribed to evaluate hypothalamic gene expression of agouti-related peptide (AgRP), neuropeptide Y (NPY), orexin-A, cocaine- and amphetamine-regulated transcript (CART), corticotrophin releasing hormone (CRH) and proopiomelanocortin (POMC), by real-time reverse transcription polymerase chain reaction. Compared to vehicle, vaspin injection significantly decreased feeding, while chemerin and omentin-1 had no effect in the tested dose. Vaspin treatment significantly decreased NPY and increased POMC gene expression. Chemerin treatment led to a significant increase of both AgRP and POMC gene expression. Omentin-1 treatment did not modify gene expression of the investigated peptides. Therefore, vaspin is an adipokine triggering anorectic pathways in the hypothalamus, where reduction of NPY and increase of POMC mRNA levels mediate feeding inhibition. Chemerin and omentin-1 have no effect on feeding in the tested dose.

Need for analgesics/drugs of abuse: a comparison between headache patients and addicts by the Leeds Dependence Questionnaire (LDQ)

Our aim was to compare the need for analgesics/drugs of abuse between headache patients—chronic and episodic headache sufferers—and addicts, by the Leeds Dependence Questionnaire (LDQ). This is a self-completion 10-item instrument to measure dependence upon a variety of substances. We administered the LDQ questionnaire to 122 chronic daily headache (CDH) sufferers who had been taking one dose of analgesic drug every day for at least 1 year; 71 subjects suffering from episodic headache (EH) using analgesics only occasionally; 115 consecutive drug addicts (DA) with a diagnosis of substance dependence. The mean LDQ total score was similar in the CDH (11.58 ± 6.35) and DA (10.37 ± 6.51) groups, and for both it was significantly higher than the score in the EH (5.61 ± 3.00) group (P < 0.001). The CDH group had the highest scores, and higher scores than the DA group (Z = −8.18, P < 0.001) in item 8, assessing the primacy of effect over the kind of analgesic used, and in item 10 (Z = −5.03, P < 0.001), asking if it is difficult to live without the analgesic; the DA group had the highest scores, and higher scores than the CDH group, in item 9 (Z = −5.07, P < 0.001) addressing the need for the continued administration of the drug to maintain well-being, and in item 3 (Z =−2.39, P < 0.05), exploring compulsion to start the use of the drug. The EH group had lower scores in all items (P < 0.05) except for item 9, where there was no difference from CDH group; the EH group had also lower scores (P < 0.001) than the DA group, except for item 8, where, instead, the score was higher than in the DA group (Z = −5.33, P < 0.001). A strong link develops between chronic headache patients and the analgesics they use. This sort of ‘dependence’ appears to be a consequence of headache, originating from the necessity for the analgesic to cope with everyday life.

Further evidence that melanocortins prevent myocardial reperfusion injury by activating melanocortin MC3 receptors

In rats subjected to myocardial ischemia/reperfusion, melanocortin peptides, including gamma(1)-melanocyte-stimulating hormone (gamma(1)-MSH), are able to exert a protective effect by stimulating brain melanocortin MC(3) receptors. A non-melanocortin receptor belonging to a group of receptors for Phe-Met-Arg-Phe-NH(2) (FMRFamide)-like peptides may be involved in some of the cardiovascular effects of the gamma-MSHs. FMRFamide-like peptides and gamma(1)-/gamma(2)-MSH share, among other things, the C-terminal Arg-Phe sequence, which seems to be essential for cardiovascular effects in normal animals. So we aimed to further investigate which receptor and which structure are involved in the protective effects of melanocortins in anesthetized rats subjected to myocardial ischemia by ligature of the left anterior descending coronary artery (5 min), followed by reperfusion. In saline-treated rats, reperfusion induced, within a few seconds, a high incidence of ventricular tachycardia and ventricular fibrillation, and a high percentage of death within the 5 min of observation period. Reperfusion was associated with a massive increase in free radical blood levels and with an abrupt and marked fall in systemic arterial pressure. The i.v. treatment (162 nmol/kg) during the ischemic period with the adrenocorticotropin fragment 1-24 [ACTH-(1-24): the reference protective melanocortin which binds all melanocortin receptors], as well as with both the melanocortin MC(3) receptor agonists gamma(2)-MSH and [D-Trp(8)]gamma(2)-MSH, reduced the incidence of ventricular tachycardia, ventricular fibrillation and death, the increase in free radical blood levels and the fall in arterial pressure. On the contrary, gamma(2)-MSH-(6-12) (a fragment unable to bind melanocortin receptors) was ineffective. Such protective effect was prevented by the melanocortin MC(3)/MC(4) receptor antagonist SHU 9119. In normal (i.e., not subjected to myocardial ischemia/reperfusion) rats, the same i.v. dose (162 nmol/kg) of gamma(2)-MSH, [D-Trp(8)]gamma(2)-MSH and gamma(2)-MSH-(6-12) provoked a prompt and transient increase in arterial pressure; on the other hand, ACTH-(1-24), which lacks the C-terminal Arg-Phe sequence, decreased arterial pressure, but only at higher doses. Heart rate of normal rats was not affected by any of the assayed peptides. The present data confirm and extend our previous findings that melanocortins prevent myocardial reperfusion injury by activating melanocortin MC(3) receptors. Moreover, they further support the notion that, in normal rats, cardiovascular effects of gamma-MSHs are mediated by receptors for FMRFamide-like peptides, for whose activation, but not for that of melanocortin MC(3) receptors, the C-terminal Arg-Phe structure being relevant.

An Hydroalcoholic Chamomile Extract Modulates Inflammatory and Immune Response in HT29 Cells and Isolated Rat Colon

Inflammatory bowel diseases (IBDs) are chronic disorders characterized by disruption and ulceration of the colonic mucosa or of any part of the digestive tract (Crohns disease). Antioxidant/anti‐inflammatory herbal extract supplementation could represent an innovative approach to contrast IBDs. Clinical trials demonstrated the efficacy of natural formulas, containing chamomile, in patients with gastrointestinal disorders. This is consistent, albeit in part, with the antioxidant and anti‐inflammatory properties of chamomile. The aim of the present study was to explore the possible protective role of a chamomile extract, on human colorectal adenocarcinoma HT29 cell, and rat colon specimens treated with lipopolysaccharide (LPS) to induce an inflammatory stimulus, a well established model of acute ulcerative colitis. In this context, the activities of different biomarkers of inflammation and lipid peroxidation such as ROS, myeloperoxidase (MPO), serotonin (5‐HT), prostaglandin (PG)E2, 8‐iso‐prostaglandin (8‐iso‐PG)F2α, NF‐kB, tumor necrosis factor (TNF)α and interleukin (IL)‐6 were assessed. We found that chamomile extract was as effective as sulfasalazine (2 mg/ml) in reducing the production of MPO, 5‐HT, IL‐6, NF‐kB, TNFα, PGE2 and 8‐iso‐PGF2α, after inflammatory stimulus. The observed modulatory effects support a rationale use of chamomile supplementation as a promising pharmacological tool for the prevention and management of ulcerative colitis in humans. Copyright

Lipid peroxidation inhibition reduces NF-κB activation and attenuates cerulein-induced pancreatitis

Increased lipid peroxidation, enhanced nuclear factor kappa-B (NF- s B) activation and augmented tumor necrosis factor- f (TNF- f ) production have been implicated in cerulein-induced pancreatitis. We investigated whether lipid peroxidation inhibition might reduce NF- s B activation and the inflammatory response in cerulein-induced pancreatitis. Male Sprague-Dawley rats of 230-250 g body weight received administration of cerulein (80 w g/kg s.c. for each of four injections at hourly intervals). A control group received four s.c. injections of 0.9% saline at hourly intervals. Animals were randomized to receive either raxofelast, an inhibitor of lipid peroxidation (20 mg/kg i.p. administered with the first cerulein injection) or its vehicle (1 ml/kg of a 10% DMSO/NaCl solution). All these rats were sacrificed 2 h after the last injection of either cerulein or its vehicle. Raxofelast administration (20 mg/kg i.p. with the first cerulein) significantly reduced malondialdehyde (MDA) levels, an index of lipid peroxidation (CER+DMSO=3.075 - 0.54 w mol/g; CER+raxofelast= 0.693 - 0.18 w mol/g; p <0.001 ), decreased myeloperoxidase (MPO) activity ( CER+DMSO=22.2 - 3.54 mU/g; CER+raxofelast=9.07 - 2.05 mU/g; p <0.01 ), increased glutathione levels (GSH) (CER+DMSO= 5.21 - 1.79 w mol/g; CER+raxofelast=15.71 - 2.14 w mol/g; p <0.001 ), and reduced acinar cell damage evaluated by means of histology and serum levels of both amylase ( CER+DMSO=4063 - 707.9 U/l; CER+raxofelast=1198 - 214.4 U/l; p <0.001 ), and lipase (CER+DMSO=1654 - 330 U/l; CER+raxofelast= 386 - 118.2 U/l; p <0.001 ), Furthermore, raxofelast reduced pancreatic NF- s B activation and the TNF- f mRNA levels and tissue content of mature protein in the pancreas. Indeed, lipid peroxidation inhibition might be considered a potential therapeutic approach to prevent the severe damage in acute pancreatitis.

Antioxidant Effects of Garlic in Young and Aged Rat Brain In Vitro

Oxidative stress plays a key role in the pathogenesis of age-related neurodegeneration, and the nonenzymatic production of 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)) may represent a reliable index of cellular oxidative damage. Garlic (Allium sativum) has been associated with peripheral antioxidant activities and therefore might prevent or reverse 8-iso-PGF(2alpha) production, but scant data are available on its possible neuroprotective effects. Therefore, we have studied the possible antioxidant effects of a garlic extract in rat brain synaptosomes obtained from young (3-month-old) and aged (14-month-old) male Wistar rats that were perfused, in vitro, with graded concentrations of a garlic extract (10-500 microg/mL). Release in the effluent was evaluated, both in the basal state and after hydrogen peroxide-induced oxidative stress. In young rats, we observed a concentration-dependent inhibitory effect of the garlic extract on brain 8-iso-PGF(2alpha) production, both basally and after hydrogen peroxide-induced oxidative stimulus. In aged rats, 8-iso-PGF(2alpha) production was not affected by the garlic extract in the basal state, whereas, after hydrogen peroxide-induced oxidative stimulus, an antioxidant effect of the garlic extract appeared only at the higher concentration tested. In conclusion, garlic supplementation could be effective in preventing brain oxidative damage in young animals, whereas the aging brain seems to be resistant to the antioxidant effects of garlic, in vitro.

Orexigenic effects of omentin-1 related to decreased CART and CRH gene expression and increased norepinephrine synthesis and release in the hypothalamus

Omentin-1, a visceral fat depot-specific secretory protein, is inversely correlated with obesity and insulin resistance. We investigated, in rats, the effects of chronic omentin-1 administration (8 μg/kg, intraperitoneally, once daily for 14-days) on feeding behavior and related hypothalamic peptides and neurotransmitters. Food intake and body weight were recorded daily throughout the study. We found a significantly increased food intake compared to controls, but only in days 10-14, while body weight significantly increased since day 12 (P<0.05). Compared with vehicle, omentin-1 treatment led to a significant reduction in both cocaine and amphetamine-regulated transcript (CART) (P<0.05) and corticotrophin releasing hormone (CRH) (P<0.05) gene expression, while pro-opiomelanocortin (POMC), agouti-related peptide (AgRP), neuropeptide Y (NPY) and orexin-A gene expression were not modified with respect to vehicle-treated rats. We also found an increase in hypothalamic levodopa (l-dopa) (P<0.05) and norepinephrine (NE) (P<0.01) synthesis, without any effect on dopamine (DA) and serotonin (5-hydroxytryptamine, 5-HT) metabolism. Furthermore, in hypothalamic synaptosomes, omentin-1 (10-100 ng/ml) stimulated basal NE release (ANOVA, P<0.0001; post hoc, P<0.001 vs. vehicle), in a dose-dependent manner, leaving unaffected both basal and depolarization-induced DA and 5-HT release. Finally, when synaptosomes were co-perfused with leptin and omentin-1, we observed that leptin was able to reverse omentin-1-induced stimulation of NE. In conclusion, the orexigenic effects of omentin-1 could be related, at least in part, to decreased CART and CRH gene expression and increased NE synthesis and release in the hypothalamus.

Glucagon-like peptide 1 (7–36) amide (GLP-1) and exendin-4 stimulate serotonin release in rat hypothalamus

Glucagon-like peptide 1 (7-36) amide (GLP-1) and exendin-4 are gastrointestinal hormones as well as neuropeptides involved in glucose homeostasis and feeding regulation, both peripherally and at the central nervous system (CNS), acting through the same GLP-1 receptor. Aminergic neurotransmitters play a role in the modulation of feeding in the hypothalamus and we have previously found that peripheral hormones and neuropeptides, which are known to modulate feeding in the central nervous system, are able to modify catecholamine and serotonin release in the hypothalamus. In the present paper we have evaluated the effects of GLP-1 and exendin-4 on dopamine, norepinephrine, and serotonin release from rat hypothalamic synaptosomes, in vitro. We found that glucagon-like peptide 1 (7-36) amide and exendin-4 did not modify either basal or depolarization-induced dopamine and norepinephrine release; on the other hand glucagon-like peptide 1 (7-36) amide and exendin-4 stimulated serotonin release, in a dose dependent manner. We can conclude that the central anorectic effects of GLP-1 agonists could be partially mediated by increased serotonin release in the hypothalamus, leaving the catecholamine release unaffected.