ABSTRACT
Objective: To describe health care resource utilization (HCRU) and associated costs in adult patients referred for specialist asthma care in Southwest Finland, by disease severity and blood eosinophil count (BEC).Methods: This non-interventional, retrospective registry study (GSK ID: HO-17-17558) utilized data from patients >18 years of age on the hospital register of the Hospital District of Southwest Finland. Data extraction was from January 1, 2004 to December 31, 2015; the index date was the first hospital visit within this period with an International Classification of Diseases-10 diagnosis code for asthma or acute severe asthma. Patients were categorized by asthma severity (based on medication use) and BEC (<300 or ≥300 cells/µL). Total and asthma-related HCRU and estimated costs were recorded the year following index and for calendar years 2004-2015.Results: Overall, 14,398 patients were included; 388 had severe asthma at index. BEC was available for 3781 patients; 1434 had a BEC ≥300 cells/µL and 2347 had a BEC <300 cells/µL. A total of 1241 patients had severe asthma; 270 patients had severe eosinophilic asthma (severe asthma and a BEC ≥300 cells/µL). Patients with severe versus non-severe asthma had higher total- and asthma-related outpatient visits, inpatient days, emergency room visits and costs per patient year; those with BEC ≥300 cells/µL versus <300 cells/µL had more outpatient visits. All recorded HCRU and associated costs were highest in patients with severe eosinophilic asthma.Conclusion: This study demonstrated a substantial burden associated with severe and/or eosinophilic asthma for adults in Finland.
Subject(s)
Asthma/economics , Asthma/epidemiology , Eosinophilia/epidemiology , Health Expenditures/statistics & numerical data , Health Resources/statistics & numerical data , Adult , Aged , Aged, 80 and over , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Asthma/physiopathology , Body Mass Index , Cost of Illness , Costs and Cost Analysis , Eosinophils/metabolism , Female , Finland , Health Resources/economics , Humans , Male , Middle Aged , Patient Acceptance of Health Care/statistics & numerical data , Retrospective Studies , Severity of Illness IndexABSTRACT
Heat shock protein 110 (HSP110) is a large molecular mass chaperone that is part of the HSP70/DnaK superfamily. In the present study, we examined the accumulation of HSP110 in Xenopus laevis A6 kidney epithelial cells. Immunoblot analysis, using a homologous antibody, detected the presence of HSP110 in A6 cells maintained at 22 degrees C. The relative levels of HSP110 accumulation increased after heat shock or sodium arsenite treatment. Immunocytochemical analysis revealed that constitutively expressed HSP110 was localized in the cytoplasm in a diffuse granular pattern with enrichment in the nucleus. In A6 cells heat shocked at 33 degrees C or 35 degrees C for 2 to 4 h, HSP110 accumulation was enhanced and detected primarily in the cytoplasm as thread- or spindle-like structures. In contrast, HSP30 was not detected constitutively and heat shock treatment of A6 cells induced a relatively uniform punctate pattern primarily in the cytoplasm. Also, treatment of A6 cells at 35 degrees C for 6 h resulted in the presence of HSP110 and HSP30 enriched in the nucleus of most cells. Finally, A6 cells treated with 25 microM sodium arsenite produced very dense HSP110 structures primarily in the cytoplasm while HSP30 was enriched in the cytoplasm in a granular pattern.
Subject(s)
Epithelial Cells/metabolism , HSP110 Heat-Shock Proteins/metabolism , Intracellular Space/metabolism , Kidney/cytology , Xenopus laevis/metabolism , Animals , Arsenites/pharmacology , Cell Line , Epithelial Cells/cytology , Epithelial Cells/drug effects , HSP30 Heat-Shock Proteins/metabolism , Heat-Shock Response/drug effects , Intracellular Space/drug effects , Protein Transport/drug effects , Sodium Compounds/pharmacology , Temperature , Xenopus Proteins/metabolismABSTRACT
Small heat shock proteins (shsps) act as molecular chaperones by preventing heat-induced aggregation and unfolding of cellular proteins by a mechanism that is still unclear. Previously we found that the C-terminal end of Xenopus shsp, hsp30C (30C), was essential for optimal chaperone activity. Examination of the C-terminal tail of 30C revealed that it had a net negative charge. Involvement of this negative charge in chaperone activity was assessed by the creation of two mutants, D209G (Asp converted to the more neutrally charged and less polar Gly at position 209) and D209/213G (Asp to Gly at position 209 and 213). Compared to 30C and D209G, D209/213G was impaired in inhibiting heat-induced citrate synthase aggregation. In rabbit reticulocyte lysate and Xenopus oocyte microinjection refolding assays the mutants were not as efficient as 30C in maintaining heat-treated luciferase in a folding competent state. Circular dichroism analysis revealed that D209G was similar in secondary structure to 30C whereas D209/213G displayed a loss of alpha-helical-like and beta-sheet structure. Also, C-terminal truncation of 30C or 30D (an hsp30 isoform) resulted in a loss of secondary structure and function. This study clearly shows that mutation of aspartic acid residues in the C-terminal end of hsp30 or its truncation disrupts secondary structure and impairs its chaperone activity.
Subject(s)
Heat-Shock Proteins/chemistry , Heat-Shock Proteins/physiology , Membrane Proteins/chemistry , Membrane Proteins/physiology , Mutation , Amino Acid Sequence , Amino Acid Substitution , Animals , Cell-Free System , Citrate (si)-Synthase/chemistry , HSP30 Heat-Shock Proteins , Heat-Shock Proteins/genetics , Membrane Proteins/genetics , Microinjections , Molecular Chaperones/chemistry , Molecular Chaperones/genetics , Oocytes , Protein Folding , Protein Structure, Secondary , Sequence Deletion , Xenopus Proteins/chemistry , Xenopus Proteins/geneticsABSTRACT
We examined the postnatal changes (days 10, 36, 84, 160, 365) of monocarboxylate transporters (MCT)1 and MCT4 in rat heart and soleus muscle. In the heart, MCT1 protein and mRNA remained unaltered from day 10 until 1 yr of age. Both MCT4 protein and mRNA in the heart were detected at 10 days of age, but the MCT4 protein and transcript were not detected thereafter. In the soleus muscle, MCT1 protein (+38%) and mRNA (+136%) increased during the first 84 days and remained stable until 1 yr of age. In contrast, soleus MCT4 protein decreased by 90% over the course of 1 yr, with the most rapid decrease (-60%) occurring by day 84 (P < 0.05). At the same time, MCT4 mRNA was increased by 74% from days 10 to 84 (P < 0.05), remaining stable thereafter. In conclusion, developmental changes in MCT transport proteins are tissue specific and isoform specific. Furthermore, it appears that MCT1 expression in the heart and MCT1 and MCT4 expression in the soleus are regulated by pretranslational processes, whereas posttranscriptional processes regulate MCT4 expression in the soleus muscle.
Subject(s)
Carrier Proteins/genetics , Carrier Proteins/metabolism , Gene Expression Regulation, Developmental , Heart/growth & development , Muscle Development , Muscle Proteins , Muscle, Skeletal/growth & development , Animals , Animals, Newborn , Body Weight , Male , Membrane Proteins/genetics , Monocarboxylic Acid Transporters , Muscle, Skeletal/metabolism , Myocardium/metabolism , Organ Size , Protein Isoforms/genetics , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Transcription, GeneticABSTRACT
We examined the isoform-specific regulation of monocarboxylate transporter (MCT)1 and MCT4 expression by contractile activity in red and white tibialis anterior muscles. After 1 and 3 wk of chronic muscle stimulation (24 h/day), MCT1 protein expression was increased in the red muscles (+78%, P < 0.05). In the white muscles, MCT1 was increased after 1 wk (+191%) and then was decreased after 3 wk. In the red muscle, MCT1 mRNA accumulation was increased only after 3 wk (+21%; P < 0.05). In the white muscle, MCT1 mRNA was increased after 1 wk (+30%; P < 0.05) and 3 wk (+15%; P < 0.05). MCT4 protein was not altered in either the red or white muscles after 1 or 3 wk. MCT4 mRNA was transiently lowered (approximately 15%) in both muscles in the 1st wk, but MCT4 mRNA levels were back to control levels after 3 wk. In conclusion, chronic contractile activity induces the expression of MCT1 but not MCT4. This increase in MCT1 alone was sufficient to increase lactate uptake from the circulation.
Subject(s)
Carrier Proteins/genetics , Gene Expression Regulation , Muscle Contraction/physiology , Muscle Proteins , Animals , Carrier Proteins/metabolism , Electric Stimulation , Glycolysis , Male , Monocarboxylic Acid Transporters , Muscle Fibers, Fast-Twitch/metabolism , Oxidation-Reduction , RNA, Messenger/metabolism , Rats , Rats, Sprague-DawleyABSTRACT
In this study, we have employed whole-mount, in situ hybridization to study the spatial pattern of hsc70 and hsp70 mRNA accumulation in normal and heat shocked embryos during Xenopus laevis development. Our findings revealed that hsc70 mRNA was constitutively present in a global fashion throughout the embryo and was not heat inducible. Accumulation of hsp70 mRNA, however, was detected only in heat shocked embryos. Furthermore, hsp70 mRNA accumulation was enriched in a tissue-specific manner in X. laevis tailbud embryos within 15 minutes of a 33 degrees C heat shock. Abundant levels of heat shock-induced hsp70 mRNA were detected in the head region, including the lens placode, the cement gland, and in the somitic region and proctodeum. Preferential heat-induced accumulation of hsp70 mRNA was first detected at a heat shock temperature of 30 degrees C. Placement of embryos at 22 degrees C after a 1-hour, 33 degrees C heat shock resulted in decreased hsp70 mRNA with time, but the message persisted in selected tissues, including the lens placode and somites. Treatment of tailbud embryos with either sodium arsenite or zinc chloride induced a tissue-specific enrichment of hsp70 mRNA in the lens placode and somitic region. These studies reveal the complex nature of the heat shock response in different embryonic tissues and suggest the presence of regulatory mechanisms that lead to a stressor-induced, tissue-specific enrichment of hsp70 mRNA.
Subject(s)
Gene Expression Regulation, Developmental , HSP70 Heat-Shock Proteins/genetics , RNA, Messenger/biosynthesis , Stress, Physiological/metabolism , Transcription, Genetic , Animals , Arsenites/pharmacology , Chlorides/pharmacology , Embryo, Nonmammalian/drug effects , Embryo, Nonmammalian/metabolism , Gene Expression Regulation, Developmental/drug effects , HSP70 Heat-Shock Proteins/biosynthesis , In Situ Hybridization , Organ Specificity , RNA, Messenger/genetics , Sodium Compounds/pharmacology , Stress, Physiological/genetics , Xenopus laevis/embryology , Zinc Compounds/pharmacologyABSTRACT
Small heat shock proteins protect cells from stress presumably by acting as molecular chaperones. Here we report on the functional characterization of a developmentally regulated, heat-inducible member of the Xenopus small heat shock protein family, Hsp30C. An expression vector containing the open reading frame of the Hsp30C gene was expressed in Escherichia coli. These bacterial cells displayed greater thermoresistance than wild type or plasmid-containing cells. Purified recombinant protein, 30C, was recovered as multimeric complexes which inhibited heat-induced aggregation of either citrate synthase or luciferase as determined by light scattering assays. Additionally, 30C attenuated but did not reverse heat-induced inactivation of enzyme activity. In contrast to an N-terminal deletion mutant, removal of the last 25 amino acids from the C-terminal end of 30C severely impaired its chaperone activity. Furthermore, heat-treated concentrated solutions of the C-terminal mutant formed nonfunctional complexes and precipitated from solution. Immunoblot and gel filtration analysis indicated that 30C binds with and maintains the solubility of luciferase preventing it from forming heat-induced aggregates. Coimmunoprecipitation experiments suggested that the carboxyl region is necessary for 30C to interact with target proteins. These results clearly indicate a molecular chaperone role for Xenopus Hsp30C and provide evidence that its activity requires the carboxyl terminal region.
Subject(s)
Heat-Shock Proteins/physiology , Membrane Proteins/physiology , Animals , Antibodies , Chromatography, Gel , Citrate (si)-Synthase/chemistry , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Escherichia coli/metabolism , HSP30 Heat-Shock Proteins , Heat-Shock Proteins/chemistry , Heat-Shock Proteins/genetics , Heat-Shock Response , Immunoblotting , Light , Luciferases/chemistry , Luciferases/immunology , Membrane Proteins/chemistry , Membrane Proteins/genetics , Molecular Chaperones , Precipitin Tests , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Scattering, Radiation , Solubility , Xenopus Proteins , Xenopus laevisABSTRACT
We employed whole-mount in situ hybridization and immunohistochemistry to study the spatial pattern of hsp30 gene expression in normal and heatshocked embryos during Xenopus laevis development. Our findings revealed that hsp30 mRNA accumulation was present constitutively only in the cement gland of early and midtailbud embryos, while hsp30 protein was detected until at least the early tadpole stage. Heat shock-induced accumulation of hsp30 mRNA and protein was first observed in early and midtailbud embryos with preferential enrichment in the cement gland, somitic region, lens placode, and proctodeum. In contrast, cytoskeletal actin mRNA displayed a more generalized pattern of accumulation which did not change following heat shock. In heat shocked midtailbud embryos the enrichment of hsp30 mRNA in lens placode and somitic region was first detectable after 15 min of a 33 degrees C heatshock. The lowest temperature capable of inducing this pattern was 30 degrees C. Placement of embryos at 22 degrees C following a 1-h 33 degrees C heat shock resulted in decreased hsp30 mRNA in all regions with time, although enhanced hsp30 mRNA accumulation still persisted in the cement gland after 11 h compared to control. In late tailbud embryos the basic midtailbud pattern of hsp30 mRNA accumulation was enhanced with additional localization to the spinal cord as well as enrichment across the embryo surface. These studies demonstrate that hsp30 gene expression can be detected constitutively in the cement gland of tailbud embryos and that heat shock results in a preferential accumulation of hsp30 mRNA and protein in certain tissues.
Subject(s)
Gene Expression Regulation, Developmental , Heat-Shock Proteins/metabolism , Heat-Shock Response/genetics , Membrane Proteins/metabolism , Animals , Embryo, Nonmammalian/metabolism , HSP30 Heat-Shock Proteins , Heat-Shock Proteins/genetics , Immunohistochemistry , In Situ Hybridization , Membrane Proteins/genetics , Organ Specificity , RNA Probes , RNA, Messenger/metabolism , Xenopus Proteins , Xenopus laevisABSTRACT
In this study we have investigated the acquisition of thermotolerance in a Xenopus laevis kidney A6 epithelial cell line at both the level of cell survival and translation. In cell survival studies, A6 cells were incubated at temperatures ranging from 22 to 35 degrees degrees C for 2 h followed by a thermal challenge at 39 degrees degrees C for 2 h and a recovery period at 22 degrees C for 24 h. Optimal acquisition of thermotolerance occurred at 33 degrees degrees C. For example, exposure of A6 cells to 39 degrees degrees C for 2 h resulted in only 3.4% survival of the cells whereas prior exposure to 33 degrees C for 2 h enhanced the survival rate to 69%. This state of thermotolerance in A6 cells was detectable after 1 h at 33 degrees C and was maintained even after 18 h of incubation. Cycloheximide inhibited the acquisition of thermotolerance at 33 degrees C suggesting the requirement for ongoing protein synthesis. The optimal temperature for the acquisition of translational thermotolerance also occurred at 33 degrees C. Treatment of A6 cells at 39 degrees C for 2 h resulted in an inhibition of labeled amino acid incorporation into protein which recovered to approximately 14% of control after 19 h at 22 degrees C whereas cells treated at 33 degrees C for 2 h prior to the thermal challenge recovered to 58% of control levels. These translationally thermotolerant cells displayed relatively high levels of the heat shock proteins hsp30, hsp70, and hsp90 compared to pretreatment at 22, 28, 30, or 35 degrees C. These studies demonstrate that Xenopus A6 cells can acquire a state of thermotolerance and that it is correlated with the synthesis of heat shock proteins.
Subject(s)
Heat-Shock Response , Kidney/physiology , Protein Biosynthesis , Animals , Cell Survival , Epithelial Cells/physiology , Heating , Kidney/cytology , Xenopus laevisABSTRACT
We have characterized the constitutive and stress-inducible pattern of immunoglobulin-binding protein (BiP) gene expression during Xenopus early development. Whole mount in situ hybridization analysis revealed that BiP mRNA was detected in unfertilized eggs, cleavage and blastula stage embryos. In gastrulae, BiP mRNA was present across the surface of the embryo, while in neurulae BiP mRNA was enriched in the neural plate, neural fold, and around the blastopore. In early and late tailbud embryos, BiP mRNA was found primarily in the dorsal region. Tunicamycin and A23187, the calcium ionophore, enhanced BiP mRNA accumulation first at the neurula stage, while heat shock induced BiP mRNA accumulation first at the gastrula stage. Compared to control, A23187- and heat shock-treated neurulae displayed relatively high levels of BiP mRNA in selected tissues, including the neural plate, neural folds, around the blastopore, and ectoderm. At the early tailbud stage, A23187 and heat shock enhanced BiP mRNA accumulation primarily in the head, somites, tail, and along the spinal cord. A similar situation was found with A23187- and heat shock-treated late tailbud embryos, except that heat-shocked embryos also displayed enhanced BiP mRNA accumulation in the epidermis. These studies demonstrate a preferential accumulation of BiP mRNA in selected tissues during development and in response to stress.
Subject(s)
Carrier Proteins/genetics , Endoplasmic Reticulum/metabolism , Gene Expression Regulation, Developmental , HSP70 Heat-Shock Proteins/genetics , Heat-Shock Proteins , Molecular Chaperones/genetics , Animals , Blotting, Northern , Calcimycin/pharmacology , Endoplasmic Reticulum Chaperone BiP , Heat-Shock Response , In Situ Hybridization , RNA, Messenger/genetics , Tunicamycin/pharmacology , Xenopus laevisABSTRACT
Trigeminal neuralgia is an example of an extreme form of neuropathic pain and continues to be a real therapeutic challenge. Although the pathophysiology of the disorder is uncertain, vascular compression of the trigeminal root resulting in damage to primary afferent neurons is thought to play a major role in the generation of pain. In the present study, we have used a recently developed rat model of trigeminal neuropathic pain, where the neuropathy is produced by a chronic constriction injury of the infraorbital branch of the trigeminal nerve (CCI-ION), and for the first time studied the effects of various pharmacological treatments on this purely sensory model of neuropathic pain. Rats with a CCI-ION consistently display a series of spontaneous behavioural abnormalities that may be indicative of trigeminal paraesthesias/dysesthesias. A hyper-responsiveness of the territory of the ligated infraorbital nerve to light mechanical stimulation with von Frey hairs also develops at 7-12 days after the injury. Pharmacological studies indicated that the mechanical hyper-responsiveness could be reversibly abolished by local injections of alphacaine into the close proximity of the injured nerve. The allodynia-like behaviour was resistant to i.v. morphine. Similarly, single and repeated injections (using the respective T 1/2 as an interval) of tricyclic antidepressants amitriptyline and clomipramine were devoid of effects on the mechanical allodynia-like behaviour. Carbamazepine was effective only after doses (> or =10 mg/kg s.c.) that already caused disturbances in motor co-ordination in the rotarod test. Repeated injections of baclofen (3 mg/kg s.c.) partially alleviated the mechanical allodynia-like behaviour without effects on rotarod performance. The partial anti-allodynic effect of a single injection (5 mg/kg) of baclofen, which was already accompanied by slight motor disturbances, could be antagonized by CGP35348, a selective GABA(B)-receptor antagonist. Functional deficits in the GABAergic system may play an important role in the pathogenesis of this purely sensory rat model of trigeminal neuropathic pain.
Subject(s)
Analgesics, Non-Narcotic/therapeutic use , Analgesics, Opioid/therapeutic use , Antidepressive Agents, Tricyclic/therapeutic use , Baclofen/therapeutic use , Carbamazepine/therapeutic use , GABA Agonists/therapeutic use , Morphine/therapeutic use , Trigeminal Neuralgia/drug therapy , Animals , Behavior, Animal/drug effects , Constriction, Pathologic/complications , Male , Pain Measurement , Physical Stimulation , Postural Balance/drug effects , Rats , Rats, Sprague-Dawley , Skin/drug effects , Skin/innervation , Trigeminal Nerve/physiopathology , Trigeminal Neuralgia/etiology , Trigeminal Neuralgia/physiopathologyABSTRACT
In this study, we have examined whether members of the small heat shock protein family, hsp 30, were capable of forming heat-induced aggregates in Xenopus laevis A6 kidney epithelial cells. Rate-zonal centrifugation coupled with immunoblot analysis demonstrated the presence of hsp30 aggregates with an estimated sedimentation coefficient of 10-16S. Also, pore exclusion limit electrophoretic analysis of labeled protein from heat-shocked A6 cells revealed four heat-induced aggregates, including a prominent 510 kDa aggregate, as well as weaker 350, 290, and 240 kDa aggregates. Immunoblot analysis of the aggregates employing an hsp30C antibody suggested that the 510 and 350 kDa aggregates were comprised of hsp30 protein. One- and two-dimensional SDS-PAGE analysis of the proteins isolated from the 510 kDa region of the pore exclusion limit electrophoretic gel confirmed the presence of 30 kDa heat-induced protein. A total of eight small hsps were present in this aggregate, suggesting that virtually all of the major small hsps in Xenopus A6 cells were involved in aggregate formation. This study also detected the presence of heat-inducible hsp70 in the 510 kDa gel fraction containing the small hsps, but it could not be determined whether it was part of the multimer complex.
Subject(s)
Heat-Shock Proteins/genetics , Membrane Proteins/genetics , Multigene Family , Xenopus laevis/genetics , Animals , Cells, Cultured , Epithelial Cells , HSP30 Heat-Shock Proteins , Kidney/cytology , Molecular Weight , Xenopus ProteinsABSTRACT
Two hindpaw injections of carrageenin were performed 7 days apart and the time-course of the vocalization thresholds to pressure (VTPP) of all the 4 paws of the rat were measured after both injections. The first injection of carrageenin induced an increase in the circumference of the injected paw and a significant reduction of the VTPPs of all the 4 paws. The pain-related behavior of both hindpaws was enhanced, when carrageenin was injected for the second time not only into the previously inflamed, but also into the contralateral hindpaw. However, the abnormal responses of the forepaws were not increased by this second hindpaw inflammation. Both after the first and the second injection of carrageenin, the decrease of the VTPPs of all 4 paws was antagonized by lidocaine with epinephrine (LE) injected into the inflamed paw. This anesthetic effect was of a shorter duration after the second than after the first injection of carrageenin. Presumably, the imprint that is left in the nervous system after the first hindpaw inflammation, takes place at a relatively limited segmental level. In addition, it is possible to influence the established sensitization of the nervous system by treating the peripheral process itself, even when the first injury has primed the nervous system to the second injury. However, there still seems to exist some excitatory influences that cannot be suppressed by the local anesthetic.
Subject(s)
Anesthetics, Local/pharmacology , Hindlimb/innervation , Inflammation/chemically induced , Lidocaine/pharmacology , Neuralgia/chemically induced , Vocalization, Animal , Analysis of Variance , Animals , Carrageenan , Edema/chemically induced , Injections, Intraperitoneal , Male , Rats , Rats, Sprague-DawleyABSTRACT
The ability of the cholecystokinin B (CCKB) receptor antagonist L-365,260 to modulate the antinociceptive action of systemic morphine was investigated using the well established rat model of localized inflammation induced by intraplantar injection of carrageenin. The effects of morphine (0.1-1 mg/kg i.v.) alone or in combination with the CCKB receptor antagonist (0.2 mg/kg s.c.) were determined at different time-points (at 1, 3 and 24 h) after the injection of carrageenin by measuring the vocalization threshold to paw pressure. L-365,260 was found to be ineffective in modulating the responses to all doses of morphine at 1 and 24 h after carrageenin. By contrast, at 3 h, the CCKB receptor antagonist reversed the ineffectiveness of the low dose (0.1 mg/kg i.v.) of morphine on the inflamed paw. Further, in the L-365,260-pretreated rats, a significant correlation between the antinociceptive effect of the low dose (0.1 mg/kg) of morphine and the intensity of the mechanical hyperalgesia was observed, indicating that the CCK control of the degree of sensitivity to opioids can vary among-the animals. Our data illustrate a differential and limited effect of L-365,260 on opioid antinociception in carrageenin-injected rats, depending on the dose of morphine, the phase of inflammation and the intensity of hyperalgesia.
Subject(s)
Benzodiazepinones/pharmacology , Hyperalgesia/drug therapy , Morphine/pharmacology , Narcotics/pharmacology , Phenylurea Compounds , Receptors, Cholecystokinin/antagonists & inhibitors , Animals , Carrageenan , Drug Synergism , Excipients , Hyperalgesia/chemically induced , Male , Neuritis/chemically induced , Neuritis/drug therapy , Nociceptors/drug effects , Pressure , Rats , Rats, Sprague-Dawley , Receptor, Cholecystokinin BABSTRACT
In this study, we report the detection of a new group of five stress-inducible basic small heat shock proteins (BShsps) in Xenopus laevis kidney epithelial A6 cells by means of two-dimensional non-equilibrium pH gradient gel electrophoresis. These basic 30-kDa small hsps are distinct from the previously described X. laevis acidic hsp30 family on the basis of their charge and lack of cross-reactivity with an hsp30 antibody. Furthermore, at least two of the five BShsps were present constitutively, an observation that has not been made with the acidic hsp30 family. The heat inducibility of the BShsps was regulated at the level of transcription as indicated by their inhibited synthesis in the presence of the transcriptional inhibitor actinomycin D. Furthermore, the optimal temperature of BShsp induction, temporal pattern of synthesis, and induction of BShsps by other stressors such as herbimycin A and sodium arsenite were similar to those reported for the acidic hsp30 family. This study suggests that X. laevis contains at least two unique groups of small heat shock proteins that are coordinately expressed.
Subject(s)
Epithelial Cells/metabolism , Heat-Shock Proteins/metabolism , Kidney/metabolism , Xenopus/metabolism , Animals , Arsenites/pharmacology , Benzoquinones , Blotting, Northern , Cells, Cultured , Dactinomycin/pharmacology , Dose-Response Relationship, Drug , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/pharmacology , Lactams, Macrocyclic , Protein Synthesis Inhibitors/pharmacology , Quinones/pharmacology , Rifabutin/analogs & derivatives , Sodium Compounds/pharmacologyABSTRACT
1. We evaluated the ability of the functional antagonist at the glycine site of the N-methyl-D-aspartate (NMDA) receptor complex, (+)-(1-Hydroxy-3-aminopyrrolodine-2-one) ((+)-HA966), to modulate the antinociceptive action of systemic morphine in a rat model of neuropathic pain produced by chronic constriction injury to the sciatic nerve. Mechanical (vocalization threshold to hindpaw pressure) and thermal (struggle latency to hindpaw immersion into a water bath) stimuli were used. 2. In the mechanical test, morphine (0.05, 0.1 and 0.3 mg kg(-1), i.v.) alone produced dose-dependent effects in both neuropathic and uninjured rats. Likewise, morphine (0.1, 0.3 and 1 mg kg(-1), i.v.) dose-dependently increased struggle latencies of the nerve-injured hindpaw in the hot noxious (46 degrees C) test but was ineffective in the non-noxious warm (44 degrees C) and cold (10 degrees C) test. 3. Pretreatment with (+)-HA966 (2.5 mg kg(-1), s.c.) dose-dependently enhanced the effect of morphine in the mechanical test with the relative potency being nerve-injured hindpaw > contralateral hindpaw > uninjured rat. 4. Likewise, (+)-HA966 dose-dependently enhanced the effect of morphine against a hot (46 degrees C) stimulus and produced, in combination with morphine, a dose-dependent effect against a warm (44 degrees C) stimulus. In the cold (10 degrees C) test, (+)-HA966 reversed the ineffectiveness of the highest dose of morphine. 5. Naloxone blocked the effect of the combination of (+)-HA966 with morphine in all tests. The drug combination produced no motor deficits in animals using the rotarod test. 6. These findings suggest that combined administration of antagonists, acting at the glycine site of the NMDA receptor complex and morphine may be a promising approach in the treatment of neuropathic and acute pain.
Subject(s)
Analgesics, Opioid/pharmacology , Excitatory Amino Acid Antagonists/pharmacology , Morphine/pharmacology , Nociceptors/drug effects , Peripheral Nervous System Diseases/drug therapy , Pyrrolidinones/pharmacology , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Analgesics, Opioid/therapeutic use , Animals , Binding Sites , Cold Temperature , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Therapy, Combination , Excitatory Amino Acid Antagonists/therapeutic use , Glycine , Hot Temperature , Male , Morphine/therapeutic use , Motor Activity/drug effects , Naloxone/pharmacology , Narcotic Antagonists/pharmacology , Pain/drug therapy , Pyrrolidinones/therapeutic use , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/chemistry , Stress, MechanicalSubject(s)
Analgesics/pharmacology , Neurons/drug effects , Adrenergic alpha-2 Receptor Agonists , Analgesics/therapeutic use , Animals , Bradykinin Receptor Antagonists , Cyclooxygenase Inhibitors/pharmacology , Cyclooxygenase Inhibitors/therapeutic use , Cytokines/biosynthesis , Humans , Nitric Oxide Synthase/antagonists & inhibitors , Purinergic P1 Receptor Agonists , Receptors, Cholecystokinin/antagonists & inhibitors , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, Neurokinin-2/antagonists & inhibitors , Receptors, Neurokinin-3/antagonists & inhibitorsABSTRACT
The ability of pretreatment by the selective cholecystokinin-B (CCK(B)) receptor antagonist L-365,260 (0.2 mg/kg s.c.) to prevent the development of tolerance to the antinociceptive action of morphine was evaluated by a well-established rat model of unilateral peripheral mononeuropathy. The 4-day pretreatment regimens (saline, L-365,260 or morphine alone, or with the combination of L-365,260 and morphine) were begun on postoperative day 12. The experiments were performed on day 16, when the pain-related behavior reached a stable maximum. Behavioral test based on a mechanical stimulus (vocalization threshold to paw pressure) and relatively low acute doses of systemic morphine (0.1, 0.3 and 1.0 mg/kg i.v.) were used. On day 16, the base-line vocalization threshold to paw pressure values of the groups pretreated with one of the four regimens were similar, which suggests that the pretreatments had no effect on the development of mechanical allodynia. Pretreatment with morphine alone (10 mg/kg s.c., two times a day during 4 days) induced a complete tolerance to the antinociceptive effect of acute morphine (0.1-1.0 mg/kg i.v.). However, pretreatment with the combination of L-365,260 with morphine completely prevented the development of tolerance to the antinociceptive effect of acute i.v. morphine. The effect of acute morphine in this latter pretreatment group was dose dependent, naloxone reversible and similar to the effect of acute morphine seen in the saline-pretreated group. Our results suggest that in this well-characterized model of neuropathic pain, the development of tolerance to the antinociceptive effect of systemic morphine can be prevented by systemic coadministration of the CCK(B) antagonist L-365,260. We further show, that in contrast to a tonic activity of the endogenous opioidergic system, a tonic activity of the endogenous CCK system cannot be revealed in this rat model of neuropathic pain.
Subject(s)
Analgesics, Opioid/pharmacology , Morphine/pharmacology , Peripheral Nervous System Diseases/physiopathology , Phenylurea Compounds , Receptors, Cholecystokinin/antagonists & inhibitors , Animals , Benzodiazepinones/pharmacology , Drug Tolerance , Male , Naloxone/pharmacology , Rats , Rats, Sprague-Dawley , Receptor, Cholecystokinin B , Vocalization, Animal/drug effectsABSTRACT
The ability of the selective cholecystokinin(B) (CCK(B)) receptor antagonist L-365,260 (0.2 mg/kg s.c.) to modulate the antinociceptive action of relatively low doses of systemic morphine (0.1, 0.3 and 1.0 mg/kg i.v.) was evaluated using a well established rat model of peripheral unilateral mononeuropathy. Behavioural tests based on both mechanical (vocalization threshold to paw pressure) and thermal (struggle latency after immersion of the paw into a cold (10 degrees C), warm (44 degrees C) or hot (46 degrees C) water bath) stimuli were used. Experiments were performed 2 weeks after the surgery when the pain-related behaviour has fully developed. We demonstrated a differential effect of L-365,260 depending both on the dose of morphine and the test used. Pretreatment with the CCK(B) receptor antagonist (0.2 mg/kg) inverted the ineffectiveness of the lowest dose (0.1 mg/kg i.v.) of morphine against the noxious (46 degrees C) thermal stimulus, and the effect of the combination was equal to that seen after the dose 0.3 mg/kg of morphine alone. Likewise, in the mechanical test, the already enhanced effect of this dose (0.1 mg/kg) of morphine on the nerve-injured paw was further increased (by 4-fold) after L-365,260 pretreatment. These effects were abolished by naloxone (0.01 mg/kg i.v.). However, the effects of the higher doses (0.3 and 1.0 mg/kg i.v.) of morphine against the mechanical or noxious thermal stimuli were not significantly enhanced by pretreatment with the CCK(B) receptor antagonist. Further, L-365,260 was found to be completely ineffective in modulating the responses to morphine at 10 degrees C and at 44 degrees C.
Subject(s)
Analgesics/administration & dosage , Benzodiazepinones/administration & dosage , Morphine/administration & dosage , Phenylurea Compounds , Receptors, Cholecystokinin/antagonists & inhibitors , Animals , Cold Temperature , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Synergism , Hot Temperature , Male , Naloxone/pharmacology , Narcotic Antagonists/pharmacology , Pain/drug therapy , Pain/etiology , Rats , Rats, Sprague-Dawley , Receptor, Cholecystokinin B , Sciatic Nerve/drug effects , Sciatic Nerve/injuries , Sciatic Nerve/physiopathology , Stress, Mechanical , Vocalization, Animal/drug effectsABSTRACT
We have isolated a full-length cDNA clone encoding a Xenopus laevis immunoglobulin binding protein (BiP; also called glucose-regulated protein or grp78). The Bip cDNA sequence includes an open reading frame of 1,965 bp encoding a 655 amino acid protein with an N-terminal hydrophobic leader sequence and a C-terminal KDEL tetrapeptide which has been found in other lumenal proteins of the endoplasmic reticulum. The 3' untranslated region contains a polyadenylation and an adenylation control element (ACE) as well as a putative mRNA instability sequence. The Xenopus BiP amino acid sequence displayed high identity with BiP from other vertebrates including chicken (91.3%), rat (90.7%), and human (89.9%). Northern hybridization analysis demonstrated that BiP mRNA was present constitutively in the Xenopus A6 kidney epithelial cell line and that BiP mRNA levels could be enhanced by treatment of the cells with galactose-free media, 2-deoxyglucose, 2-deoxygalactose, glucosamine, tunicamycin, heat shock, dithiothreitol, and the calcium ionophore, A23187. Finally, while BiP mRNA was detected in all of the adult tissues examined, the relative level of BiP mRNA differed dramatically between organs. For example, relatively high levels of BiP mRNA were detected in liver with moderate levels in testis, ovary and heart and reduced levels in eye and muscle tissue.