Analysis of PIK3CA Mutation Concordance and Frequency in Primary and Different Distant Metastatic Sites in Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The purpose of this study was to investigate the concordance rate of PIK3CA mutations between primary and matched distant metastatic sites in patients with breast cancer and to verify whether there are differences in the frequency of PIK3CA hotspot mutations depending on the metastatic sites involved. @*Materials and Methods@#Archived formalin-fixed paraffin-embedded (FFPE) specimens of primary breast and matched distant metastatic tumors were retrospectively obtained for 49 patients. Additionally, 40 archived FFPE specimens were independently collected from different breast cancer metastatic sites, which were limited to three common sites: the liver, brain, and lung. PIK3CA mutations were analyzed using droplet digital PCR, including hotspots involving exons 9 and 20. @*Results@#After analysis of 49 breast tumors with matched metastasis sites, 87.8% showed concordance in PIK3CA mutation status. According to PIK3CA hotspot mutation testing in 89 cases of breast cancer metastatic sites, the proportion of PIK3CA mutations at sites of metastasis involving the liver, brain, and lung was 37.5%, 28.6%, and 42.9%, respectively, which did not result in statistical significance. @*Conclusion@#The high concordance of PIK3CA mutation status between primary and matched metastasis sites suggests that metastatic sites, regardless of the metastatic organ, could be considered sample sources for PIK3CA mutation testing for improved therapeutic strategies in patients with metastatic breast cancer.

Social Anxiety and Social Networking Service Addiction Proneness in University Students: The Mediating Effects of Experiential Avoidance and Interpersonal Problem

Objective@#This study examined the mediating effects of experiential avoidance and interpersonal problems on the relationship between social anxiety and social networking service (SNS) addiction proneness. @*Methods@#An online survey was conducted on 400 university students in their 20s across Republic of Korea. The scales used in the study were the Social Interaction Anxiety Scale (SIAS), Korean Acceptance-Action Questionnaire-II (K-AAQ-II), Short form of the Korean Inventory of Interpersonal Problems Circumplex Scale (KIIP-SC), and SNS addiction proneness scale for university students. For data analysis, structural equation modeling was conducted, and phantom variables were used to verify the significance of individual indirect effects of the multiple mediation model. @*Results@#Social anxiety had no direct effect on SNS addiction proneness. Experiential avoidance and interpersonal problems completely mediate the relationship between social anxiety and SNS addiction proneness sequentially. @*Conclusion@#Our result suggests that experiential avoidance leads to interpersonal problems and SNS addiction proneness. In other words, it is important to alleviate experiential avoidance in treating or preventing interpersonal problems and SNS addiction proneness among university students with social anxiety.

Brain Factor-7® improves learning and memory deficits and attenuates ischemic brain damage by reduction of ROS generation in stroke in vivo and in vitro / 한국실험동물학회지

Brain Factor-7® (BF-7), silk fibroin peptide, is known to be effective in improvement of memory and learning ability. In this study, the effects of BF-7 (10 mg/kg, p.o., pre-treatment for 7 days and post-treatment for 7 days) on neuroprotection and memory and learning functions were investigated in a rat model of transient focal cerebral ischemia and a gerbil model of transient global forebrain ischemia. Furthermore, to find the mechanism of BF-7, we examined the neuroprotective and antioxidative effects of BF-7 in vitro using neuroblastoma (SH-SY5Y) cells. In vivo model, treatment with BF-7 significantly reduced the number of errors in 8-arm maze test and significantly increased latency time in passive avoidance test at 7 days after focal ischemia compared to those in the vehicle-treated group. In addition, treatment with BF-7 significantly decreased the infarct size or neuronal death at 7 day following transient ischemia compared to that in the vehicle-treated group. In vitro model, 10 or 20 μg/ml of BF-7 treatment significantly increased cell viability in dose-dependent manner. In addition, oxidative stress was significantly attenuated in the ischemic cells, showing that 10 or 20 μg/ml of BF-7 treatment significantly reduced the generation of reactive oxygen species (ROS) compared to that in the ischemic cells. These results indicate that BF-7 treatment can attenuate ischemic damages and improve memory deficits via reduction of ROS generation.

Decreased Aquaporin 4 and 6 mRNAs in Patients With Chronic Otitis Media With Otorrhea

OBJECTIVES: Aquaporins (AQPs) are integral membrane proteins engaged in the modulation of water homeostasis, but the roles they play in chronic otitis media (COM) have not been well investigated. Accordingly, we undertook document relations between the mRNA expressions of AQPs and COM, and explored the relation between these expressions and otorrhea, which is one of the most common symptoms of COM. METHODS: Levels of the mRNAs of AQP 1, 2, 3, 4, 5, 6, 8, and 10 were assayed by real-time polymerase chain reaction in inflammatory tissue samples from 81 patients with COM with or without otorrhea. Relationships between AQP mRNA levels and the presence or absence of otorrhea, the presence or absence of bacteria, hearing threshold levels, types of hearing loss, and clinical manifestations were also evaluated. RESULTS: AQP 1, 2, 3, 4, 5, 6, 8, and 10 mRNAs were expressed in inflammatory tissues obtained from all 81 patients with COM with or without otorrhea. AQP 5 mRNA was most expressed in, followed in descending order by AQP 3, 1, 10, 6, 8, 2, and 4. There were no significant intergroup differences in terms of age, sex, duration of illness, levels of hearing loss in both ears, or incidences of conductive or sensorineural hearing loss. However, AQP 4 (P=0.035) and 6 (P=0.085) mRNA levels were significantly lower in the otorrhea group. In addition, bacteria culture positivity (P=0.014) and the incidence of sensorineural hearing loss (P=0.020) were higher in the otorrhea group. CONCLUSION: AQP 1, 2, 3, 4, 5, 6, 8, and 10 are involved in the development of COM. Specifically, it shows reductions in AQP 4 and 6 mRNA levels, as observed in the otorrhea group, have an effect on the clinical manifestations of COM.

Extract Promotes Neurogenesis in the Hippocampal Dentate Gyrus of the Adult Mouse through Increasing Expressions of Brain-Derived Neurotrophic Factor and Tropomyosin-Related Kinase B / 中华医学杂志(英文版)

<p><b>Background</b>Glehnia littoralis has been used for traditional Asian medicine, which has diverse therapeutic activities. However, studies regarding neurogenic effects of G. littoralis have not yet been considered. Therefore, in this study, we examined effects of G. littoralis extract on cell proliferation, neuroblast differentiation, and the maturation of newborn neurons in the hippocampus of adult mice.</p><p><b>Methods</b>A total of 39 male ICR mice (12 weeks old) were randomly assigned to vehicle-treated and 100 and 200 mg/kg G. littoralis extract-treated groups (n = 13 in each group). Vehicle and G. littoralis extract were orally administrated for 28 days. To examine neurogenic effects of G. littoralis extract, we performed immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU, an indicator for cell proliferation) and doublecortin (DCX, an immature neuronal marker) and double immunofluorescence staining for BrdU and neuronal nuclear antigen (NeuN, a mature neuronal marker). In addition, we examined expressional changes of brain-derived neurotrophic factor (BDNF) and its major receptor tropomyosin-related kinase B (TrkB) using Western blotting analysis.</p><p><b>Results</b>Treatment with 200 mg/kg, not 100 mg/kg, significantly increased number of BrdU-immunoreactive () and DCX cells (48.0 ± 3.1 and 72.0 ± 3.8 cells/section, respectively) in the subgranular zone (SGZ) of the dentate gyrus (DG) and BrdU/NeuN cells (17.0 ± 1.5 cells/section) in the granule cell layer as well as in the SGZ. In addition, protein levels of BDNF and TrkB (about 232% and 244% of the vehicle-treated group, respectively) were significantly increased in the DG of the mice treated with 200 mg/kg of G. littoralis extract.</p><p><b>Conclusion</b>G. littoralis extract promots cell proliferation, neuroblast differentiation, and neuronal maturation in the hippocampal DG, and neurogenic effects might be closely related to increases of BDNF and TrkB proteins by G. littoralis extract treatment.</p>

Comparison between cerebral state index and bispectral index during desflurane anesthesia / 대한마취과학회지

BACKGROUND: Cerebral state index (CSI) is an anesthesia depth monitor alternative to bispectral index (BIS). Published comparative studies have used propofol or sevoflurane. However, studies using desflurane have not been reported yet. Different volatile anesthetics have different electroencephalography signatures. The performance of CSI may be different in desflurane anesthesia. Therefore, the objective of this study was to compare CSI and BIS during desflurane anesthesia. METHODS: Thirty-three patients were recruited. Desflurane and remifentanil were used to maintain general anesthesia. BIS and CSI were recorded simultaneously every minute. End-tidal concentration of desflurane was maintained at 4% from the beginning of surgery for 5 minutes. Pairwise data of CSI and BIS were obtained five times at one-minute intervals. This process was repeated in the order of 6%, 8%, and 10%. RESULTS: BIS and CSI were negatively correlated with the end-tidal concentration of desflurane with a similar degree of correlation (correlation coefficient BIS: –0.847, CSI: –0.844). The relationship between CSI and BIS had a good linearity with a slope close to 1 (R2 = 0.905, slope = 1.01). For the relationship between CSI and BIS at each end-tidal concentration of desflurane, CSI and BIS showed good linearity in 4% and 10% (R2 = 0.559, 0.540). However, the linearity and slope were decreased in 6% and 8% (R2 = 0.163, 0.014). CONCLUSIONS: CSI showed an equivalent degree of overall performance compared to BIS in desflurane anesthesia. Accounting for previous literature, CSI can be used as a good substitute for BIS regardless of the kind of anesthetics used.

Clinical Characteristics and Short-term Outcomes of Acute Low Frequency Sensorineural Hearing Loss With Vertigo

OBJECTIVES: This study analyzed short-term prognosis in patients with acute low frequency hearing loss (ALHL), and also investigate hearing recovery rates in patients with ALHL accompanied vertigo. METHODS: Retrospective medical record review of the patients who received treatment for ALHL between June 2005 and June 2015 were analyzed. Of the 84 patients, 53 were without vertigo, and 31 were with vertigo. Of the 31 patients, eight were treated with steroids, seven with diuretics alone, and 16 with both. Clinical and auditory characteristics before and after treatment were compared in these three groups. RESULTS: Pure tone audiometry after 8 weeks of treatment showed that patients with vertigo had significantly higher than patients without vertigo (P=0.020). Patients with vertigo who recovered from ALHL had a greater tendency to receive early treatment than patients who did not recover. Patients who received the two steroid therapy groups (steroids alone and steroids plus diuretics) had a higher recovery rate than patients who received diuretics alone (P=0.043 and P=0.037, respectively). CONCLUSION: The prognosis of patients with ALHL is worse in those with vertigo compared to without vertigo. The hearing recovery rate in patients with vertigo tends to be higher in those treated with steroids than with diuretics alone.

The activation of α₂-adrenergic receptor in the spinal cord lowers sepsis-induced mortality

The effect of clonidine administered intrathecally (i.t.) on the mortality and the blood glucose level induced by sepsis was examined in mice. To produce sepsis, the mixture of D-galactosamine (GaLN; 0.6 g/10 ml)/lipopolysaccharide (LPS; 27 µg/27 µl) was treated intraperitoneally (i.p.). The i.t. pretreatment with clonidine (5 µg/5 µl) increased the blood glucose level and attenuated mortality induced by sepsis in a dose-dependent manner. The i.t. post-treatment with clonidine up to 3 h caused an elevation of the blood glucose level and protected sepsis-induced mortality, whereas clonidine post-treated at 6, 9, or 12 h did not affect. The pre-treatment with oral D-glucose for 30 min prior to i.t. post-treatment (6 h) with clonidine did not rescue sepsis-induced mortality. In addition, i.t. pretreatment with pertussis toxin (PTX) reduced clonidine-induced protection against mortality and clonidine-induced hyperglycemia, suggesting that protective effect against sepsis-induced mortality seems to be mediated via activating PTX-sensitive G-proteins in the spinal cord. Moreover, pretreatment with clonidine attenuated the plasma tumor necrosis factor α (TNF-α) induced by sepsis. Clonidine administered i.t. or i.p. increased p-AMPKα1 and p-AMPKα2, but decreased p-Tyk2 and p-mTOR levels in both control and sepsis groups, suggesting that the up-regulations of p-AMPKα1 and p-AMPKα2, or down-regulations of p-mTOR and p-Tyk2 may play critical roles for the protective effect of clonidine against sepsis-induced mortality.

Effect of Age and Severity of Facial Palsy on Taste Thresholds in Bell's Palsy Patients

BACKGROUND AND OBJECTIVES: To investigate whether taste thresholds, as determined by electrogustometry (EGM) and chemical taste tests, differ by age and the severity of facial palsy in patients with Bell's palsy. SUBJECTS AND METHODS: This study included 29 patients diagnosed with Bell's palsy between January 2014 and May 2015 in our hospital. Patients were assorted into age groups and by severity of facial palsy, as determined by House-Brackmann Scale, and their taste thresholds were assessed by EGM and chemical taste tests. RESULTS: EGM showed that taste thresholds at four locations on the tongue and one location on the central soft palate, 1 cm from the palatine uvula, were significantly higher in Bell's palsy patients than in controls (p0.05). The severity of facial palsy did not affect taste thresholds, as determined by both EGM and chemical taste tests (p>0.05). The overall mean electrical taste thresholds on EGM were higher in younger Bell's palsy patients than in healthy subjects, with the difference at the back-right area of the tongue differing significantly (p0.05). CONCLUSIONS: Electrical taste thresholds were higher in Bell's palsy patients than in controls. These differences were observed in younger, but not in older, individuals.

Effect of D-glucose feeding on mortality induced by sepsis

Sepsis is the life-threatening response to infection which can lead to tissue damage, organ failure, and death. In the current study, the effect of orally administered D-glucose on the mortality and the blood glucose level induced by D-Galactosamine (GaLN)/lipopolysaccharide (LPS)-induced sepsis was examined in ICR mice. After various amounts of D-glucose (from 1 to 8 g/kg) were orally fed, sepsis was induced by injecting intraperitoneally (i.p.) the mixture of GaLN /LPS. Oral pre-treatment with D-glucose dose-dependently increased the blood glucose level and caused a reduction of sepsis-induced mortality. The oral post-treatment with D-glucose (8 g/kg) up to 3 h caused an elevation of the blood glucose level and protected the mortality observed in sepsis model. However, D-glucose post-treated at 6, 9, or 12 h after sepsis induction did not affect the mortality and the blood glucose level induced by sepsis. Furthermore, the intrathecal (i.t.) pretreatment once with pertussis toxin (PTX; 0.1 microg/5 ml) for 6 days caused a reduction of D-glucose-induced protection of mortality and hyperglycemia. Furthermore, once the hypoglycemic state is continued up to 6 h after sepsis initiated, sepsis-induced mortality could not be reversed by D-glucose fed orally. Based on these findings, it is assumed that the hypoglycemic duration between 3 and 6 h after the sepsis induction may be a critical time of period for the survival. D-glucose-induced protective effect against sepsis-induced mortality appears to be mediated via activating PTX-sensitive G-proteins in the spinal cord. Finally, the production of hyperglycemic state may be critical for the survival against the sepsis-induced mortality.

Characteristics of Patients with Hearing Aids according to the Degree and Pattern of Hearing Loss

BACKGROUND AND OBJECTIVES: This study was designed to assess the characteristics of patients according to the degree and audiogram shape of hearing loss and the association of these characteristics with hearing aids (HA) choice, return rate, and cause of return. SUBJECTS AND METHODS: This study included 460 individuals who received HAs from 2011 to 2015. The relationships between type of HA and age, primary and accompanying symptoms, HA choice and return and cause of return were evaluated according to the degree and pattern of hearing loss. RESULTS: HA type did not differ significantly according to the degree and pattern of hearing loss. Intensity of hearing loss was greater in male than in female (p<0.05). Open and completely-in-canal types of HA decreased with age (p<0.05). As degree of hearing loss intensified, behind-the-ear and in-the-ear types increased and Open type decreased (p<0.05). The HA return rate was 9.7%, but was not associated with degree or pattern of hearing loss. The main causes of HA return were costs, psychological fears and adaptive failure. CONCLUSIONS: Choice of HA is affected by age, sex, and degree and pattern of hearing loss. HA for hearing rehabilitation in patients with hearing loss can be personalized according to each patient's characteristics and tendencies.

In Vitro Antifungal Activity and Mode of Action of 2',4'-Dihydroxychalcone against Aspergillus fumigatus

2',4'-Dihydroxychalcone (2',4'-DHC) was identified from a heat shock protein 90 (Hsp90)-targeting library as a compound with Hsp90 inhibitory and antifungal effects. In the presence of 2',4'-DHC (8 microg/mL), radial growth of Aspergillus fumigatus was inhibited 20% compared to the control, and green pigmentation was completely blocked. The expression of the conidiation-associated genes abaA, brlA, and wetA was significantly decreased (approximately 3- to 5-fold) by treatment with 2',4'-DHC. The expression of calcineurin signaling components, cnaA and crzA, was also significantly reduced. The inhibitory effects of 2',4'-DHC on metabolic activity and mycelial growth were significantly enhanced by combination treatment with itraconazole and caspofungin. Docking studies indicated that 2',4'-DHC bind to the ATPase domain of Hsp90. These results suggest that 2',4'-DHC act as an Hsp90-calcinurin pathway inhibitor.

Effect of Sulfonylureas Administered Centrally on the Blood Glucose Level in Immobilization Stress Model

Sulfonylureas are widely used as an antidiabetic drug. In the present study, the effects of sulfonylurea administered supraspinally on immobilization stress-induced blood glucose level were studied in ICR mice. Mice were once enforced into immobilization stress for 30 min and returned to the cage. The blood glucose level was measured 30, 60, and 120 min after immobilization stress initiation. We found that intracerebroventricular (i.c.v.) injection with 30 microg of glyburide, glipizide, glimepiride or tolazamide attenuated the increased blood glucose level induced by immobilization stress. Immobilization stress causes an elevation of the blood corticosterone and insulin levels. Sulfonylureas pretreated i.c.v. caused a further elevation of the blood corticosterone level when mice were forced into the stress. In addition, sulfonylureas pretreated i.c.v. alone caused an elevation of the plasma insulin level. Furthermore, immobilization stress-induced insulin level was reduced by i.c.v. pretreated sulfonylureas. Our results suggest that lowering effect of sulfonylureas administered supraspinally against immobilization stress-induced increase of the blood glucose level appears to be primarily mediated via elevation of the plasma insulin level.

Radiological Assessment of the Effect of Congenital C3-4 Synostosis on Adjacent Segments

STUDY DESIGN: Retrospective case series. PURPOSE: To assess the effect of non-kyphotic aligned congenital C3-4 synostosis on the adjacent segment in 10 patients. OVERVIEW OF LITERATURE: In the cervical spine, fusion disease at the adjacent motion segments may be a risk factor for potential neurological compromise and death. METHODS: Radiograms of 10 patients 13 to 69 years of age presenting with neck/shoulder discomfort or pain with or without trauma history were examined. C3-4 synostosis was found incidentally in all patients on routine examination radiographs of cervical spine. RESULTS: Adjacent segment disease (ASD) was not found in the three patients younger than 39 years of age. Five of the 10 (50%) patients, including a 67-year-old man, did not develop spondylosis in any of the cervical mobile segments. Spondylosis was observed only in the caudal 1-2 mobile segments in the remaining five patients. The youngest was a 40-year-old male who had spondylosis in the two caudal mobile segments (C4-5 and C5-6). Spondylosis was limited to the two close caudal mobile segments and was not in the cranial segments. Flaring of the lower part of synostotic vertebra associated with advanced narrowed degenerate disc was evident in five patients. CONCLUSIONS: Mobile segment spondylosis in the individuals with congenital monosegment C3-4 synostosis over age of 40 years may be a natural manifestation of aging and is not solely an adjacent segment disease directly and fully related with congenital C3-4 synostosis.

The Modulatory Role of Spinally Located Histamine Receptors in the Regulation of the Blood Glucose Level in D-Glucose-Fed Mice

The possible roles of spinal histamine receptors in the regulation of the blood glucose level were studied in ICR mice. Mice were intrathecally (i.t.) treated with histamine 1 (H1) receptor agonist (2-pyridylethylamine) or antagonist (cetirizine), histamine 2 (H2) receptor agonist (dimaprit) or antagonist (ranitidine), histamine 3 (H3) receptor agonist (alpha-methylhistamine) or antagonist (carcinine) and histamine 4 (H4) receptor agonist (VUF 8430) or antagonist (JNJ 7777120), and the blood glucose level was measured at 30, 60 and 120 min after i.t. administration. The i.t. injection with alpha-methylhistamine, but not carcinine slightly caused an elevation of the blood glucose level. In addition, histamine H1, H2, and H4 receptor agonists and antagonists did not affect the blood glucose level. In D-glucose-fed model, i.t. pretreatment with cetirizine enhanced the blood glucose level, whereas 2-pyridylethylamine did not affect. The i.t. pretreatment with dimaprit, but not ranitidine, enhanced the blood glucose level in D-glucose-fed model. In addition, alpha-methylhistamine, but not carcinine, slightly but significantly enhanced the blood glucose level D-glucose-fed model. Finally, i.t. pretreatment with JNJ 7777120, but not VUF 8430, slightly but significantly increased the blood glucose level. Although histamine receptors themselves located at the spinal cord do not exert any effect on the regulation of the blood glucose level, our results suggest that the activation of spinal histamine H2 receptors and the blockade of spinal histamine H1 or H3 receptors may play modulatory roles for up-regulation and down-regulation, respectively, of the blood glucose level in D-glucose fed model.

A Case with Empty Sella Syndrome Combined with Multiple Anterior Pituitary Hormone Deficiencies Presenting as Hypoglycemic Coma / 고신대학교의과대학학술지

A 55-year-old male was admitted to emergency department with a hypoglycemic shock of unknown origin. He was presented with tonic seizure activity after admission. Initial diagnostic procedure could exclude diabetes mellitus, drug side effects, and exogenous insulin application. Detailed evaluation of the patient's history revealed that the patient had experienced repeated hypoglycemic episodes for 2 years. He was diagnosed with hypothyroidism six years ago. Initial laboratory investigations revealed hypoglycemia, hyponatremia, and low plasma cortisol level (0.18 microg/dL). Sellar magnetic resonance imaging showed empty sella. Replacement therapy with hydrocortisone resulted in the improvement of clinical symptoms. Combined pituitary stimulation test with exception of hypoglycemia induced growth hormone and cortisol stimulation test was performed. The response of thyroid stimulating hormone, prolactin, follicle-stimulating hormone, and luteinizing hormone was normal. We report the case of empty sella syndrome associated with hypoglycemic shock due to with multiple anterior pituitary hormone deficiencies.

The Change of Thyroid Stimulating Hormone Values of Healthy Subjects According to Temperature and Aging / 고신대학교의과대학학술지

OBJECTIVES: We conducted a study to investigate the normal range for TSH and within-individual variations of TSH according to temperature and aging. PATIENTS AND METHODS: We enrolled patients who underwent periodic medical examinations five times over a six year period (2007.8~2013.6). Anthropometric data and thyroid ultrasonography were evaluated, and serum TSH, T3, and T4 were assayed. RESULTS: Subjects were 19-64 years old, 120 were female, and 208 were male. Reference ranges for TSH were 0.53-4.94 mIU/L in the first test, 0.49-5.61 mIU/L in the second test, 0.46-6.06 mIU/L in the third test, 0.48-5.99 mIU/L in the fourth test, and 0.52-6.3 mIU/L in the fifth test. When the TSH level was analyzed according to temperature and sex, mean TSH was higher in months in which the average monthly temperatures were below 10degrees C in Jinju, Gyeongnam and female. The aging and low temperatures are associated with increased serum TSH concentrations in the within-individual. CONCLUSIONS: This study showed that aging is associated with increased serum TSH concentrations in the within-individual and serum TSH concentrations are different in the within-individual according to the temperature.

Repaglinide, but Not Nateglinide Administered Supraspinally and Spinally Exerts an Anti-Diabetic Action in D-Glucose Fed and Streptozotocin-Treated Mouse Models

We have recently demonstrated that some anti-diabetic drugs such as biguanide and thizolidinediones administered centrally modulate the blood glucose level, suggesting that orally administered anti-diabetic drugs may modulate the blood glucose level by acting on central nervous system. The present study was designed to explore the possible action of another class of anti-diabetic drugs, glinidies, administered centrally on the blood glucose level in ICR mice. Mice were administered intracerebroventricularly (i.c.v.) or intrathecally (i.t.) with 5 to 30 microg of repaglinide or nateglinide in D-glucose-fed and streptozotocin (STZ)-treated models. We found that i.c.v. or i.t. injection with repaglinide dose-dependently attenuated the blood glucose level in D-glucose-fed model, whereas i.c.v. or i.t. injection with nateglinide showed no modulatory action on the blood glucose level in D-glucose-fed model. Furthermore, the effect of repaglinide administered i.c.v. or i.t. on the blood glucose level in STZ-treated model was studied. We found that repaglinide administered i.c.v. slightly enhanced the blood glucose level in STZ-treated model. On the other hand, i.t. injection with repaglinide attenuated the blood glucose level in STZ-treated model. The plasma insulin level was enhanced by repaglinide in D-glucose-fed model, but repaglinide did not affect the plasma insulin level in STZ-treated model. In addition, nateglinide did not alter the plasma insulin level in both D-glucose-fed and STZ-treated models. These results suggest that the anti-diabetic action of repaglinide appears to be, at least, mediated via the brain and the spinal cord as revealed in both D-glucose fed and STZ-treated models.

Effect of Cholera Toxin Administered Supraspinally or Spinally on the Blood Glucose Level in Pain and D-Glucose Fed Animal Models

In the present study, the effect of intrathecal (i.t.) or intracerebroventricular (i.c.v.) administration with cholera toxin (CTX) on the blood glucose level was examined in ICR mice. The i.t. treatment with CTX alone for 24 h dose-dependently increased the blood glucose level. However, i.c.v. treatment with CTX for 24 h did not affect the blood glucose level. When mice were orally fed with D-glucose (2 g/kg), the blood glucose level reached to a maximum level at 30 min and almost returned to the control level at 120 min after D-glucose feeding. I.c.v. pretreatment with CTX increased the blood glucose level in a potentiative manner, whereas i.t. pretreatment with CTX increased the blood glucose level in an additive manner in a D-glucose fed group. In addition, the blood glucose level was increased in formalin-induced pain animal model. I.c.v. pretreatment with CTX enhanced the blood glucose level in a potentiative manner in formalin-induced pain animal model. On the other hand, i.t. pretreatment with CTX increased the blood glucose level in an additive manner in formalin-induced pain animal model. Our results suggest that CTX administered supraspinally or spinally differentially modulates the regulation of the blood glucose level in D-glucose fed model as well as in formalin-induced pain model.

Hop Extract Produces Antinociception by Acting on Opioid System in Mice

In the present study, the antinociceptive profiles of hop extract were characterized in ICR mice. Hop extract administered orally (from 25 to 100 mg/kg) showed an antinociceptive effect in a dose-dependent manner as measured in the acetic acid-induced writhing test. Antinociceptive action of hop extract was maintained at least for 60 min. Moreover, cumulative response time of nociceptive behaviors induced with intraplantar formalin injection was reduced by hop extract treatment during the 2nd phases. Furthermore, the cumulative nociceptive response time for intrathecal injection of substance P (0.7 microg) or glutamate (20 microg) was diminished by hop extract. Intraperitoneal pretreatment with naloxone (an opioid receptor antagonist) attenuated antinociceptive effect induced by hop extract in the writhing test. However, methysergide (a 5-HT serotonergic receptor antagonist) or yohimbine (an alpha2-adrenergic receptor antagonist) did not affect antinociception induced by hop extract in the writhing test. Our results suggest that hop extract shows an antinociceptive property in various pain models. Furthermore, the antinociceptive effect of hop extract may be mediated by opioidergic receptors, but not serotonergic and alpha2-adrenergic receptors.