Abstract
Therapeutic modulation of pain with morphine and other opioids is associated with significant variation in both effects and adverse effects in individual patients. Many factors including ...gene polymorphisms have been shown to contribute to the interindividual variability in the response to opioids. The aim of this study was to investigate the significance of
UGT
2
B
7
,
OPRM
1
and
ABCB
1
polymorphisms for interindividual variability in morphine‐induced analgesia in patients undergoing hysterectomy. The frequency of these polymorphisms was also investigated in forensic autopsies as morphine is also a very commonly abused drug. Blood samples were collected from 40 patients following abdominal hysterectomy, 24 hr after initiation of analgesia through a patient‐controlled analgesia (
PCA
) pump. Samples were genotyped and analysed for morphine and its metabolites. We also genotyped approximately 200 autopsies found positive for morphine in routine forensic analysis. Patients homozygous for
UGT
2
B
7
802
C
needed significantly lower dose of morphine for pain relief. The same trend was observed for patients homozygous for
ABCB
1
1236
T
and 3435
T
, as well as to
OPRM
1
118
A
. The dose of morphine in patients included in this study was significantly related to variation in
UGT
2
B
7
T
802
C
. Age was significantly related to both dose and concentration of morphine in blood. Regression analysis showed that 30% of differences in variation in morphine dose could be explained by
SNP
s in these genes. The genotype distribution was similar between the forensic cases and the patients. However, the mean concentration of morphine was higher in forensic cases compared to patients. We conclude that gene polymorphisms contribute significantly to the variation in morphine concentrations observed in individual patients.
Nucleosides like adenosine, uridine and their nucleotide derivatives (e.g. ATP and UTP) play important roles in many cellular functions, sometimes by acting as signalling molecules through binding to ...specific P2 nucleotide receptors. P2 receptors are subdivided into P2X and P2Y subfamilies, the latter of which are G-protein coupled receptors. P2Y receptors and nucleoside transporters have been detected in human and rat lungs, where they mediate effects of interest in airway diseases. The aim of this study was to investigate whether uridine has any anti-inflammatory properties in an asthma-like animal model of lung inflammation.
The Sephadex-induced lung inflammation model in Sprague–Dawley rats was chosen mainly due to its localised inflammatory response and uridine's limited oral bioavailability. The dextran beads, with or without the addition of uridine, were instilled intratracheally into the lungs, which were excised and examined after 24 h.
Sephadex alone led to massive oedema and infiltration of macrophages, neutrophils and eosinophils. Microgranulomas with giant cell formations were clearly visible around the partially degraded beads. Uridine reduced both the oedema and the infiltration of leukocytes significantly, measured as lung wet weight and leukocyte counts in bronchoalveolar lavage fluid, respectively. Uridine appeared to affect the tumour necrosis factor (TNF) levels, although this could not be statistically confirmed due to large variations within the Sephadex control group.
We conclude that uridine has anti-inflammatory effects, and that the exact mechanism(s) of action requires further study.
Therapeutic modulation of pain with morphine and other opioids is associated with significant variation in, both, effects and adverse effects in individual patients. Many factors including gene ...polymorphisms have been shown to contribute to the interindividual variability in the response to opioids. The aim of this study was to investigate the significance of UGT2B7, OPRM1 and ABCB1 polymorphisms for interindividual variability in morphine induced analgesia in patients undergoing hysterectomy. The frequency of these polymorphisms was also investigated in forensic autopsy cases as morphine is also a very commonly abused drug
Blood samples were collected from 40 patients following abdominal hysterectomy, 24 hours after initiation of analgesia through a PCA pump. Samples were genotyped and analysed for morphine and its metabolites. We also genotyped approximately 200 autopsy cases found positive for morphine in routine forensic analysis.
Patients homozygous for UGT2B7 802C needed significantly lower dose of morphine for pain relief. The same trend was observed for patients homozygous for ABCB1 1236T and 3435T, as well as to OPRM1 118A. Dose of morphine in patients included in this study was significantly related to variation in UGT2B7 T802C. Age was significantly related to both dose and concentration of morphine in blood.
Regression analysis showed that 30% of differences in variation in morphine dose could be explained by SNPs in these genes. The genotype distribution was similar between the forensic cases and the patients. However, the mean concentration of morphine was higher in forensic cases compared to patients.
We conclude that gene polymorphisms contribute significantly to the variation in morphine levels observed in individual patients.
We have previously examined isomaltitol in an in vitro static adhesion assay and were interested in investigating whether the potentially anti-inflammatory effects observed there could be relevant in ...vivo. The Sephadex-induced lung inflammation model was considered a suitablemodel due to the significant changes in global inflammatory endpoints seen upon provocation with Sephadex.
Male Sprague-Dawley rats were instilled intratracheally with Sephadex (5 mg/ml), vehicle (0.9% NaCl), isomaltitol (50 mg/ml) or a combination of isomaltitol and Sephadex. After 24 h, the lungs were weighed to measure edema and preserved for histology. Bronchoalveolar lavage fluid was used for analysis of tumor necrosis factor, cysteinyl leukotrienes, and differential and total leukocyte counts.
Differential counts showed that isomaltitol increased the neutrophil component while decreasing the eosinophilia, thus asserting a modulatory role on the usually eosinophil-dominated Sephadex-induced cell profile. Isomaltitol alone also increased edema and cysteinyl leukotrienes, and generally aggravated total inflammation in combination with Sephadex. The mechanisms were not investigated in this study, but effects could relate to a combination of isomaltitol's osmotic and structure-specific properties.
Our results show that isomaltitol can modulate the inflammatory response induced by Sephadex instillation in addition to having proinflammatory effects on its own, and may therefore provide new insights into the mechanisms of this widely used animal model. Sugar alcohols similar to isomaltitol have already been used to aid mucus clearance in cystic fibrosis patients, and it is possible that isomaltitol could also be used for this purpose.
E-selectin is a cytokine-inducible membrane glycoprotein capable of mediating adhesion of leukocytes to endothelial cells. It is highly glycosylated, containing 11 sites for N-linked glycosylation. ...N-Glycosylation of E-selectin was analyzed by endoglycosidase treatment. Analysis of immunoprecipitated E-selectin from human umbilical vein endothelial cells (HUVEC) by polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate showed that E-selectin was completely resistant to endoglycosidase H, but sensitive to peptide N-glycanase F digestion. This suggested that all N-linked oligosaccharide chains were of the complex type. The role of N-linked glycosylation in surface expression and secretion of E-selectin was studied using interleukin-1-stimulated HUVEC, cultured in the presence of the soluble glycosylation inhibitors tunicamycin or castanospermine. Cell surface expression was analyzed by indirect flow cytometry. N-Glycosylation was blocked by tunicamycin, and resulted in a significantly reduced surface expression of E-selectin, whereas castanospermine only marginally reduced E-selectin expression. The deglycosylated forms of E-selectin were also found to be fully capable of mediating adhesion of HT-29 cells in vitro. In conclusion, these studies show that E-selectin is heavily glycosylated with complex type N-linked oligosaccharides and that N-glycosylation is important for expression of E-selectin on human endothelial cells.
Highlights • Topical morphine gels for pain control were tested for partial skin graft donor sites. • 13 patients with two similar donor sites were randomised between morphine gel and placebo. • Pain ...relieving effects of morphine gel were not significantly better than placebo.
Adhesion molecules such as P-selectin are potential markers for evaluating platelet activation and studying the role of cell-cell interactions in numerous biological processes related to hemostasis ...and inflammation. The expression of P-selectin and related molecules has previously been quantified with different techniques. As an alternative to the most common method, flow cytometry, we have developed a useful ELISA method to simultaneously analyse 96 samples for platelet expression of P-selectin. Samples may be stored for at least 7 days at 4°C prior to analysis. The method is simple, reproducible, flexible and requires only standard equipment. Washed platelets (WP) from healthy male volunteers, at a concentration of 1 × 10
7/microtiter plate well, were stimulated with various known platelet activators and fixed with 0.1% formaldehyde for 10 min. The fixed WP were centrifuged to form a confluent layer in the wells and then incubated with optimal dilutions of primary antibodies (1/2000) directed against P-selectin, CD41, CD9 and secondary antibodies conjugated with alkaline phosphatase. Our results show that P-selectin expression on WP increases significantly upon stimulation with thrombin (0.1–1.0 U/ml), ADP (10 μM) and epinephrine (100 μM). The induction of P-selectin expression by thrombin is fast and has different kinetics depending on the concentration of the agonist. Prior incubation with the nitric oxide donor SNAP (10 μM) inhibits the up-regulation of P-selectin induced by sub-maximal concentrations of thrombin (
p < 0.05). This ELISA is suitable for studying the expression and regulation of P-selectin and other surface molecules on human platelets in various pathological states.
Activated platelets and endothelium surface express the cell adhesion molecule P-selectin (CD62P), which plays an important role in mediating interactions with leukocytes. Increased levels of a ...functional soluble form of P-selectin (sP-selectin) have been reported in several pathological states but it is not clear whether this circulating sP-selectin originates from platelets and/or endothelial cells. Here we describe the concurrent kinetics of intracellular storage, surface expression and release of platelet P-selectin induced by thrombin or the protein kinase C activator PMA. Platelet activation with submaximal concentrations of thrombin (0.1 U/ml) resulted in a rapid decrease of intracellular P-selectin. This decrease of intracellular P-selectin concurred with a gradual increase of surface expression and an initial increase of sP-selectin. Our results indicate that intracellular stores of P-selectin were only partly mobilized upon activation with submaximal concentrations of thrombin. A high concentration of thrombin (1.0 U/ml) induced a rapid and nearly total decrease of intracellular stores and a more pronounced, but transient, increase of surface expression. The release of P-selectin was fast and occurred during the initial activation phase. The NO donor SNAP inhibited both surface expression and release of platelet P-selectin in a similar manner. PMA (0.1-1.01 µM) mediated a more slow, gradual and sustained surface expression and release of P-selectin than thrombin. Thus, surface expression and release of platelet P-selectin show different kinetics depending on the mode of activation.
Recent reports demonstrate a role for nucleotides as inflammatory modulators. Uridine, for example, reduces oedema formation and leucocyte infiltration in a Sephadex-induced lung inflammation model. ...Tumour necrosis factor (TNF) concentration was also reduced. Previous in vivo observations indicated that 4-thiouridine might have similar effects on leucocyte infiltration and TNF release. The aim of this study was thus to investigate the effects of 4-thiouridine in greater detail. We used a Sephadex-induced acute lung inflammation model in Sprague-Dawley rats. The dextran beads were instilled intratracheally into the lungs, which were excised and examined after 24 h. Sephadex alone led to massive oedema formation and infiltration of macrophages, neutrophils and eosinophils. Microgranulomas with giant cell formations were clearly visible around the partially degraded beads. A significant increase in bronchoalveolar lavage fluid (BALF) content of TNF and leukotrienes was also seen. 4-Thiouridine co-administration affected all variables investigated in this model, i.e. oedema, microscopic and macroscopic appearance of lung tissue, total leucocyte and differential leucocyte counts in BALF, TNF and leukotrienes C₄ (LTC₄), LTD₄ and LTE₄ in BALF, indicating a reproducible anti-inflammatory effect. In conclusion, we have demonstrated that 4-thiouridine has anti-inflammatory effects similar to those of uridine. To our knowledge, this is the first demonstration of pharmacological 4-thiouridine effects in vivo. The results suggest nucleoside/nucleotide involvement in inflammatory processes, warranting further studies on nucleoside analogues as attractive new alternatives in the treatment of inflammatory diseases.
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