OBJECTIVES: To predict the structure of protein, which dictates the function it performs, a newly designed algorithm is developed which blends the concept of self-organization and the genetic algorithm. METHODS: Among many other approaches, genetic algorithm is found to be a promising cooperative computational method to solve protein structure prediction in a reasonable time. To automate the right choice of parameter values the influence of self-organization is adopted to design a new genetic operator to optimize the process of prediction. Torsion angles, the local structural parameters which define the backbone of protein are considered to encode the chromosome that enhances the quality of the confirmation. Newly designed self-configured genetic operators are used to develop self-organizing genetic algorithm to facilitate the accurate structure prediction. RESULTS: Peptides are used to gauge the validity of the proposed algorithm. As a result, the structure predicted shows clear improvements in the root mean square deviation on overlapping the native indicates the overall performance of the algorithm. In addition, the Ramachandran plot results implies that the conformations of phi-psi angles in the predicted structure are better as compared to native and also free from steric hindrances. CONCLUSIONS: The proposed algorithm is promising which contributes to the prediction of a native-like structure by eliminating the time constraint and effort demand. In addition, the energy of the predicted structure is minimized to a greater extent, which proves the stability of protein.
Enkephalin, Methionine ; Islet Amyloid Polypeptide ; Operator Regions, Genetic ; Peptides

OBJECTIVE: Adrenal medullary chromaffin cells are known to release analgesic substances such as opioides and catecholamines. Transplantation of them is a novel method that challenges current approaches in treating chronic pain. The transplantation of xenogeneic chromaffin cells into the central nervous system(CNS) supply antinociception in animals. In this study, we investigated the analgesic effects of rat adrenal medullary chromaffin cells transplanted into the CNS of the mouse. To study the antinociceptive efficacy of transplanted chromaffin cells, the survival of rat adrenal medullary chromaffin cells transplanted into the CNS of mouse was determined. METHODS: The adrenal medullary chromaffin cells isolated from rat were transplanted into the striatum of mouse. These cells were confirmed of the release of Met-enkephalin and Leu-enkephalin by HPLC, and immunoblots for tyrosine hydroxylase(TH). Two weeks after transplantation, we performed immunohistochemistry for TH to determine the survival of implanted cells and assessed pain sensitivity at the same time. RESULTS: The isolated rat adrenal medullary chromaffin cells were positive for anti-TH antibody and released Met-enkephalin and Leu-enkephalin more than rat endothelial cells. Transplanted rat chromaffin cells were stained with anti-TH antibody in striatum of mouse after 2 weeks. Pain sensitivity was reduced on the chromaffin cell-transplanted mouse compared to endothelial cell-transplanted mouse by the hot plate test. CONCLUSION: These results suggest that the rat chromaffin cells were suitably transplanted into the CNS of mouse. This approach could be used as a therapy for reducing of chronic pain induced by cancer or neuronal injury.
Animals ; Catecholamines ; Chromaffin Cells* ; Chromatography, High Pressure Liquid ; Chronic Pain ; Endothelial Cells ; Enkephalin, Leucine ; Enkephalin, Methionine ; Enkephalins ; Immunohistochemistry ; Mice* ; Neurons ; Rats ; Tyrosine

BACKGROUND: The aim of this study is to investigate the cardio-metabolic parameters and surrogate markers of insulin resistance in a discordant group of type 2 diabetes (T2DM) subjects who satisfy the Adults Treatment Panel (ATP) III criteria, but not the International Diabetes Federation (IDF) criteria, for metabolic syndrome (MetS). METHODS: We assessed the prevalence of MetS in T2DM subjects (n=167) who were selected from subjects registered at the diabetes center of Dong-A University Medical Center. We used the ATP III criteria and the IDF criteria for the diagnosis of MetS and sorted the subjects into 2 MetS groups: one group diagnosed per ATP III criteria (MetSa) and one diagnosed per IDF criteria (MetSi). We then compared the clinical characteristics, metabolic parameters (homeostasis model assessment of insulin resistance, aspartate aminotransferase, alanine aminotransferase, and uric acid values) and co-morbidities (prevalence of microalbuminuria, fatty liver, and cardiovascular disease) between the MetSa, MetSi, and discordant MetS groups. RESULTS: The prevalence of MetS in the MetSa group (73.6%) was higher than in the MetSi group (62.2%). The MetS prevalence in the discordant group was 11.4%. The discordant group showed no significant differences in clinical characteristics (except waist circumference and body mass index), metabolic parameters, or prevalence of co-morbidities, as compared with subjects with MetS by both criteria. CONCLUSION: In this study, cardio-metabolic features of the subjects diagnosed with MetS using ATP III criteria, but not IDF criteria, are not significantly different from those of subjects diagnosed with MetS using both criteria.
Academic Medical Centers ; Adenosine Triphosphate ; Adult ; Alanine Transaminase ; Aspartate Aminotransferases ; Biomarkers ; Diabetes Mellitus ; Enkephalin, Methionine ; Fatty Liver ; Humans ; Insulin Resistance ; Prevalence ; Uric Acid ; Waist Circumference

BACKGROUND: Adrenal medullary transplants into the subarachnoid space have been demonstrated to reduce pain sensitivity. This analgesia most likely results from the release of neuroactive substances, particularly catecholamines and opioid peptides from the transplanted cells into spinal cord. METHODS: Isolated bovine chromaffin cells were encapsulated with alginate and poly-L-lysine prior to implantation into rat's subarachnoid space to protect them from host immune system. And then catecholamines from encapsulated chromaffin cells were measured quantitatively in vitro by High Performance Liquid Chromatograph. The animals were randomized into 2 groups, one of which received microencapsulated chromaffin cells and the other empty capsules. The effects of such implants were evaluated on the pain behavior resulting from a chronic constriction injury of the rat sciatic nerve for 30 days. RESULTS: Catecholamine concentration in cerebrospinal fluid (CSF) was analyzed. Data (mean SD) are considered significant at P <0.05 (ANOVA for repeated measure and Dunnett's test). Continuous release of catecholamine and met-enkephalin with responsiveness to nicotine stimulation was measured from encapsulated cells in vitro. A significant reduction of allodynic response to acetone evaporation was observed in the animals implanted with cell loaded capsules compared to control animals with empty capsules. Catecholamine concentration in CSF was higher in the cell loaded capsule group. There were no complications related to implantation. CONCLUSION: We found that encapsulated chromaffin cells released continuously catehcolamines and opioids peptides in vitro and in the CSF. Those results may prove chromaffin cell's anagesic effect indirectly.
Acetone ; Analgesia ; Analgesics, Opioid ; Animals ; Capsules ; Catecholamines* ; Cerebrospinal Fluid ; Chromaffin Cells* ; Constriction ; Drug Compounding ; Enkephalin, Methionine ; Immune System ; Nicotine ; Opioid Peptides ; Peptides ; Rats ; Sciatic Nerve ; Spinal Cord ; Subarachnoid Space

BACKGROUNDPreconditioning with repeated electroacupuncture (EA) could mimic ischemic preconditioning to induce cerebral ischemic tolerance in rats. The present study was designed to investigate whether mu (micro)-, delta (delta)- or kappa (kappa)-opioid receptors are involved in the neuroprotection induced by repeated EA preconditioning.

METHODSThe rats were pretreated with naltrindole (NTI), nor-binaltorphimine (nor-BNI) or D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), which is a highly selective delta-, kappa- or micro-opioid receptor antagonist respectively, before each EA preconditioning (30 minutes per day, 5 days). Twenty-four hours after the last EA treatment, the middle cerebral artery occlusion (MCAO) was induced for 120 minutes. The brain infarct volume was determined with 2, 3, 5-triphenyltetrazolium chloride staining at 24 hours after MCAO and compared with that in rats which only received EA preconditioning. In another experiment, the met-enkephalin-like immunoreactivity in rat brain was investigated by immunohistochemistry in both EA preconditioning and control rats.

RESULTSThe EA preconditioning reduced brain infarct volume compared with the control rats (P = 0.000). Administration of both NTI and CTOP attenuated the brain infarct volume reduction induced by EA preconditioning, presenting with larger infarct volume than that in the EA preconditioning rats (P < 0.001). But nor-BNI administration did not block the infarct volume reduction induced by EA preconditioning, presenting with smaller infarct volume than the control group rats (P = 0.000). The number of met-enkephalin-like immunoreactivity positive neurons in the EA preconditioning rats was more than that of the control rats (P = 0.000).

CONCLUSIONRepeated EA preconditioning stimulates the release of enkephalins, which may bind delta- and micro-opioid receptors to induce the tolerance against focal cerebral ischemia.

Animals ; Brain Ischemia ; prevention & control ; Electroacupuncture ; Enkephalin, Methionine ; analysis ; Immunohistochemistry ; Ischemic Preconditioning ; Male ; Naltrexone ; analogs & derivatives ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Opioid, delta ; physiology ; Receptors, Opioid, mu ; physiology ; Somatostatin ; analogs & derivatives ; pharmacology

OBJECTIVETo observe the analgesic effect of electroacupuncture (EA) on collagen-induced arthritis (CIA) rats and its regulating effect on inflammation reaction and the endogenous opioid system of synovial tissues. Methods A total of 30 healthy male Wistar rats were randomly divided into a control group, a model group and an EA group, 10 rats in each one. The chronic pain model of CIA rats was made by cattle type-II collagen in the model group and EA group. Rats in the EA group were treated with EA at "Zusanli" (ST 36) and "Kunlun" (BL 60) for 30 min from 16th day after model establishment, once a day for consecutive 10 days. Rats in the control group did not receive any treatment. Rats in the model group were treated with fixation as the EA group. Threshold of pain, arthritis index, paw swelling were measured before model establishment and 16 d, 20 d, 23 d and 25 d after model establishment. The levels of beta-endorphin (β-END), met-enkephalin (met-ENK), dynorphin A (Dyn A) were measured by radioimmunoassay; the mRNA expressions of mu opioid receptor (MOR), kappa opioid receptor (KOR) and delta opioid receptor (DOR) in synovial tissues of CIA rats were detected by I quantitative polymerase chain reaction (qPCR).

RESULTSCompared with the control group, threshold of pain was reduced (all P<0. 01), arthritis index was increased (all P<0. 01) and paw swelling was increased (all P<0. 01) in the model group on the 16th day, 20th day, 23rd day, 25th day after model establishment. Compared with the model group, the threshold of pain was increased in the EA group (all P<0. 01), arthritis index and paw swelling were reduced (all P<0. 01) on the 23rd day and 25th day after model establishment. Compared with the control group, the level of Dyn A in synovial tissues of CIA rats was increased in the model group (P<0. 01); the mRNA expressions of MOR, KOR and DOR were down-regulated lower than 0. 5 fold of normal level. Compared with the model group, the level of β-END in synovial tissues of the knee joint was increased in the EA group (P<0. 05), and the mRNA expressions of MOR, KOR and DOR in synovial tissues of CIA rats were up-regulated more than 2 folds of normal level.

CONCLUSIONThe intervention of EA on chronic pain of CIA rats is superior, which is likely to be related with effects of EA on anti-inflammation and up-regulation of synovial tissue β-END and MOR, KOR, DOR.

Acupuncture Analgesia ; Acupuncture Points ; Analgesics, Opioid ; immunology ; Animals ; Arthritis, Rheumatoid ; immunology ; therapy ; Cattle ; Chronic Pain ; immunology ; therapy ; Dynorphins ; genetics ; immunology ; Electroacupuncture ; Enkephalin, Methionine ; genetics ; immunology ; Humans ; Male ; Rats ; Rats, Wistar ; Receptors, Opioid, mu ; genetics ; immunology ; Synovial Fluid ; immunology ; beta-Endorphin ; genetics ; immunology

The present study investigated the effects of intrathecal (i.t.) application of bovine adrenal medulla 22 (BAM22), an endogenous opioid peptide potently activating opioid receptors and sensory neuron-specific receptor (SNSR), on a model of complete Freund's adjuvant (CFA)-induced inflammatory pain. Unilateral, but not bilateral, inflammatory pain was induced by intraplantar (i.pl.) injection of CFA in one side, as indicated by the shortened paw withdrawal latency and the increased edema of paw. Paw withdrawal latency test, paw edema determination and immunohistochemistry were used in CFA-induced inflammatory pain model after i.t. administration of BAM22 or saline. It was found that administration of BAM22 dose-dependently attenuated CFA-induced hyperalgesia and edema, and resumed antinociceptive effects against thermal stimulation in behavioral test. In 10 nmol BAM22 group, paw withdrawal latency was resumed to 83.2% of normal, and edema increased only by 60% of normal at 48 h. The potency of BAM22 was 33.5% of maximal possible effect (MPE) at 24 h, and the antinociception persisted for at least 1 h. Furthermore, i.t. treatment of 10 nmol BAM22 evidently decreased the expressions of CFA-evoked neuronal nitric oxide synthase (nNOS)-positive cells and calcitonin gene-related peptide (CGRP)-immunoreactivity positive nerve fibers by 25.6% (P<0.01) and 25.2% (P<0.001) compared with saline group, respectively, at L3-L5 segments of the spinal cord. Small and medium CGRP-positive cells were 57.4% and 35.2% in dorsal root ganglion (DRG) in 10 nmol BAM22 group, respectively, which were remarkably lower than those in saline group (P<0.001). The present study suggests that BAM22 relieves CFA-induced thermal hyperalgesia in the early phase and resumes antinociceptive effects through down-regulation of nNOS and CGRP expressions in DRG and spinal cord, which is possibly mediated via SNSR.
Animals ; Calcitonin Gene-Related Peptide ; metabolism ; Enkephalin, Methionine ; analogs & derivatives ; pharmacology ; Freund's Adjuvant ; Hyperalgesia ; etiology ; physiopathology ; Inflammation ; chemically induced ; complications ; Male ; Nitric Oxide Synthase Type I ; metabolism ; Pain ; etiology ; physiopathology ; Pain Measurement ; drug effects ; Protein Precursors ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, G-Protein-Coupled ; physiology

The purpose of the present study was to examine the effect of naltrexone, an opioid antagonist, on secretion of catecholamines (CA) evoked by cholinergic nicotinic stimulation and membrane-depolarization from the isolated perfused rat adrenal gland and to establish the mechanism of its action. Naltrexone (3x10 (-6) M) perfused into an adrenal vein for 60 min produced time-dependent inhibition in CA secretory responses evoked by ACh (5.32x10 (-3) M), high K+ (5.6x10 (-2) M), DMPP (10 (-4) M) and McN-A-343 (10 (-4) M). Naltrexone itself did also fail to affect basal CA output. In adrenal glands loaded with naltrexone (3x10 (-6) M), the CA secretory responses evoked by Bay-K-8644, an activator of L-type Ca2+ channels and cyclopiazonic acid, an inhibitor of cytoplasmic Ca2+-ATPase, were also inhibited. However, in the presence of met-enkephalin (5x10 (-6) M), a well-known opioid agonist, the CA secretory responses evoked by ACh, high K+, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly inhibited. Collectively, these experimental results demonstrate that naltrexone inhibits greatly CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as that by membrane depolarization. It seems that this inhibitory effect of naltrexone does not involve opioid receptors, but might be mediated by blocking both the calcium influx into the rat adrenal medullary chromaffin cells and the uptake of Ca2+ into the cytoplasmic calcium store, which are at least partly relevant to the direct interaction with the nicotinic receptor itself.
(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride ; 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester ; Adrenal Glands ; Adrenal Medulla* ; Animals ; Calcium ; Catecholamines ; Chromaffin Cells ; Cytoplasm ; Dimethylphenylpiperazinium Iodide ; Enkephalin, Methionine ; Membranes ; Naltrexone* ; Rats* ; Receptors, Nicotinic* ; Receptors, Opioid ; Veins