Seizure-related stress and arousal responses mediate a relationship between anxiety trait and state in epilepsy.

BACKGROUND: Epilepsy causes substantial psychological distress and anxiety, primarily due to seizures. However, the impact of stress responses and changes in arousal and their association with anxiety patterns in patients with epilepsy (PWE) remains unclear. This study aimed to investigate the relationships among seizures, stress and arousal characteristics, and trait and state anxiety characteristics in PWE. METHODS: Our sample consisted of 159 outpatients with epilepsy recruited from five institutions in Japan in 2020. Participants completed the State-Trait Anxiety Inventory-Form JYZ (STAI) and the Japanese-Stress Arousal Check List (J-SACL). We analyzed the correlations between inventory scores and clinical information. Using principal component analysis (PCA), we derived epilepsy-specific stress/arousal characteristics, which accounted for high arousal and low-stress levels, termed epilepsy-specific stress or arousal response (ESAR), from the J-SACL scores. We conducted a mediation analysis to assess the mediating role of ESAR in the relationship between traits and state anxiety. RESULTS: We found significant correlations between J-SACL stress and arousal factors (r = -0.845, p < 0.001), ESAR and seizure frequency (r = -0.29, p < 0.001), ESAR and trait anxiety scores on the STAI (r = -0.77, p < 0.0001), and ESAR and state anxiety scores on the STAI (r = -0.60, p < 0.0001). Mediation analysis supported by the Monte Carlo method revealed that ESAR significantly mediated the association between trait and state anxiety. CONCLUSIONS: These findings elucidate the epilepsy-specific stress and arousal characteristics and their roles in mediating traits and state anxiety. These results may reflect the long-term clinical course and unique emotion recognition tendencies in epilepsy.

Effect of retinoic acid signaling on Ripply3 expression and pharyngeal arch morphogenesis in mouse embryos.

BACKGROUND: Pharyngeal arches (PA) are sequentially generated in an anterior-to-posterior order. Ripply3 is essential for posterior PA development in mouse embryos and its expression is sequentially activated in ectoderm and endoderm prior to formation of each PA. Since the PA phenotype of Ripply3 knockout (KO) mice is similar to that of retinoic acid (RA) signal-deficient embryos, we investigated the relationship between RA signaling and Ripply3 in mouse embryos. RESULTS: In BMS493 (pan-RAR antagonist) treated embryos, which are defective in third and fourth PA development, Ripply3 expression is decreased in the region posterior to PA2 at E9.0. This expression remains and its distribution is expanded posteriorly at E9.5. Conversely, high dose RA exposure does not apparently change its expression at E9.0 and 9.5. Knockout of retinaldehyde dehydrogenase 2 (Raldh2), which causes more severe PA defect, attenuates sequential Ripply3 expression at PA1 and reduces its expression level. EGFP reporter expression driven by a 6 kb Ripply3 promoter fragment recapitulates the endogenous Ripply3 mRNA expression during PA development in wild-type, but its distribution is expanded posteriorly in BMS493-treated and Raldh2 KO embryos. CONCLUSION: Spatio-temporal regulation of Ripply3 expression by RA signaling is indispensable for the posterior PA development in mouse.

Role of obstetricians in promoting pregnancy-related knowledge among women with epilepsy in Japan.

The importance of informing women with epilepsy (WWE) of pregnancy-related issues when they are of reproductive age is well recognized. However, in Japan, education on pregnancy-related issues for these patients is insufficient. Obstetricians encounter patients who have self-discontinued their medications upon realizing they are pregnant. In this study, we aimed to assess the needs and understand knowledge levels regarding pregnancy-related issues among Japanese WWE. We contacted 400 board-certified epileptologists and asked them to administer our questionnaire to their patients; 51 responses were analyzed. Among all participating WWE, 100% were taking medication at the time of the study, 34% had given birth, and 63% expressed a desire to have children in the near future. Additionally, the median questionnaire score on pregnancy-related matters was as low as 9.5 out of 13 points. Only 31% of WWE knew that the mode of delivery is not always cesarean delivery. Among WWE, 62.7% stated that they had received counseling about pregnancy-related matters. Opinions differed regarding the optimum timing for counseling according to whether patients had received counseling. As for topics WWE wished to have explained to them, inheritance of epilepsy by their children ranked highly. The average satisfaction level with counseling was 5.6 of 7 points. Regarding satisfaction with counseling, there was a significant difference between WWE who expressed a desire to receive information from obstetricians and those who did not. In summary, we believe that our study shows that Japanese WWE remain ill-informed about pregnancy-related issues and that existing counseling must be revised. Obstetricians must play a role in preconception counseling.

Physician requests by patients with malignant pleural mesothelioma in Japan.

BACKGROUND: Malignant pleural mesothelioma (MPM) is a fatal and rare disease that is caused by the inhalation of asbestos. Treatment and care requests made by MPM patients to their physicians were collected and analyzed. METHODS: This cross-sectional survey was part of a larger study (N = 133) regarding the quality of life of MPM patients. Specific responses to two open-ended questions related to patients' requests regarding treatment and care were quantified, analyzed and divided into categories based on content. RESULTS: Responses (N = 217) from MPM patients (N = 73) were categorized into 24 subcategories and then abstracted into 6 categories. The majority of requests were related to patient-physician communication. Patients wanted clear and understandable explanations about MPM and wanted their physician to deliver treatment based on the patient's perspective by accepting and empathizing with their anxiety and pain. Patients expected physicians to be dedicated to their care and establish an improved medical support system for MPM patients. CONCLUSION: Patients with MPM had a variety of unmet needs from their physicians. Physicians who provide care to MPM patients should receive training in both communication skills and stress management. A multidisciplinary care system that includes respiratory and palliative care for MPM patients should be established.

Quality of life of survivors of malignant pleural mesothelioma in Japan: a cross sectional study.

BACKGROUND: Previous studies have indicated that people with malignant pleural mesothelioma (MPM) have a poor quality of life (QOL); however, information about the QOL of people with MPM in Japan is anecdotal. The aims of this study were to investigate the QOL of survivors of MPM in Japan and to determine the factors that correlate with their QOL. METHODS: This was a cross sectional study. The included patients were those diagnosed with MPM in Japan. We created a self-administered questionnaire consisting of 64 questions. The questionnaires were sent to hospitals and patient advocacy groups, distributed to the patients, completed, and sent back to the researchers by postal mail. QOL was assessed with the European Organization for Research and Treatment of Cancer 16 questionnaire (QLQ) and the short version of the core domains of the Comprehensive Quality of Life Outcome questionnaire (CoQoLo). RESULTS: In total, 133 questionnaires were collected. The QLQ assessments demonstrated that the survivors of MPM most frequently complained of fatigue, pain, sleep disturbances, and dyspnea. The symptom scales were acceptable, but the functional scales were significantly poorer for the patients with poor performance statuses (PSs). The short CoQoLo assessment was very unfavorable for 'Being free from physical pain.' Being a long-term survivor and a survivor with a poor PS were significantly correlated with poor global health status. CONCLUSIONS: Survivors of MPM have impaired function, a variety of symptoms, and lower QOL. Survivors of MPM, even those in good physical condition, need broad support.

Public awareness and experiences associated with epilepsy in Japan, 2013-2017.

BACKGROUND: Public attitudes and stigma toward epilepsy may limit people with epilepsy (PWE) in seeking treatment and participating in social activities. The prevalence of epilepsy is approximately 0.8% in Japan, similar to rates reported in other countries. Although epilepsy is relatively common, few studies have investigated public awareness about epilepsy in Japan. Recently, several serious car accidents in Japan involving PWE resulted in pedestrian fatalities. Traffic accidents involving PWE have been reported extensively and repeatedly in the media since 2011. In 2013 and 2017, our research group conducted a large investigation of awareness about epilepsy targeting the general public. Previous studies have reported that knowledge is one of the factors involved in improving attitudes and reducing stigma. The aim of the current study was to compare survey results, especially regarding knowledge of epilepsy, and capture changes in public awareness between 2013 and 2017. METHODS: A total of 2160 people (1080 in each year) participated, with a total of 540 women in each year, aged 20-79 years. Participants lived in the greater Tokyo area as well as the Tohoku and Kansai regions of Japan. All participants answered survey questions online in January 2013 and April 2017. We analyzed five questions regarding the participants' demographic data, nine questions regarding knowledge about epilepsy, and five questions regarding experiences with epilepsy. For questions investigating the respondents' knowledge about epilepsy, we counted only the correct answers and scored these for each respondent. RESULTS: Knowledge scores decreased from 2013 to 2017, demonstrated by statistical analysis. However, the effect size was very small. Knowledge scores among the following groups were higher in both 2013 and 2017: people who had read or heard about epilepsy, those who had witnessed people having an epileptic seizure, people who had acquaintances who were PWE, those who had PWE in their family, and people who had studied medicine or worked in a medical profession. CONCLUSION: We revealed that participants who had some experience with epilepsy had higher knowledge levels in both 2013 and 2017. This suggests that such experiences could be important for motivating people to seek appropriate and accurate knowledge about epilepsy, and could result in a reduction of stigma. Greater awareness is needed among the general public in Japan about various aspects of epilepsy.

Longitudinal investigation into implicit stigma of epilepsy among Japanese medical students before and after mass media coverage of car accidents associated with people with epilepsy.

OBJECTIVE: Public attitudes and stigma toward epilepsy may limit patient motivation for treatment and participation in social activities. Stigma research requiring individuals to report personal beliefs is useful but is subject to social desirability bias. Self-reporting methods often do not capture implicit attitudes; therefore, in this study, implicit stigma was measured using the implicit association test (IAT), which is a word sorting task to minimize this bias. Recently, in Japan, several serious car accidents caused by people with epilepsy (PWE) resulted in pedestrian fatalities. Traffic accidents involving PWE have been reported extensively and repeatedly in the media since 2011. The present study aimed to examine differences in implicit stigma toward epilepsy among medical students in 2010, 2013, and 2016. METHODS: We recruited 41 medical students in 2010, 44 medical students in 2013 and 42 medical students in 2016. We investigated the strength of conceptual associations between the words "Epilepsy" or "Hypertension", and "Safety" or "Danger" in the IAT. RESULTS: The association between the words "Epilepsy" and "Danger" was stronger in 2013 compared with that in 2010; however, the association was weaker in 2016 compared with that in 2013. There was no significant difference between 2010 and 2016. CONCLUSION: The change in IAT results between 2010 and 2013 might be due to the traffic accident involving PWE in Japan. However, the result in 2016 might indicate that the implicit attitudes toward epilepsy were improved to the same level as those in 2010.

Changes in the duration and frequency of deviant stimuli engender different mismatch negativity patterns in temporal lobe epilepsy.

Mismatch negativity (MMN) is an event-related potential (ERP) component that reflects preattentive sensory memory functions. Previous research revealed that MMN is generated by distinct sources in the frontal and temporal lobes. Event-related potential abnormalities have been shown in the vicinity of seizure foci in epilepsy. Additionally, no published study has investigated the MMN in response to variations in both frequency and duration deviants in patients with temporal lobe epilepsy (TLE). The aims of this study were to compare MMN changes between the frontocentral sites and the mastoid sites and to compare MMNs related to deviant stimuli with different durations and frequencies in patients with TLE. We recorded MMNs elicited by duration and frequency changes of deviant stimuli from 15 patients with TLE and 15 healthy control subjects. We found that mean MMN amplitudes related to duration deviants were lower in patients with TLE at the mastoid sites relative to controls, whereas the MMN amplitudes at the frontocentral sites did not differ between the two groups. There were no MMN differences related to frequency deviants between TLE subjects and controls at the frontocentral sites or the mastoid sites. Mismatch negativity parameters related to duration deviants did not correlate with those related to deviant frequencies in the group with TLE. The present findings suggest selective impairments among multiple mismatch generators in TLE and suggest that processing of temporal information of auditory stimuli is selectively disturbed in TLE. Changes in MMN amplitudes related to duration deviants at the mastoid sites may represent deficits in time-dependent processing in TLE.

[Formation of oxalate in oxaliplatin injection diluted with infusion solutions].

Oxaliplatin use can cause acute peripheral neuropathy characterized by sensory paresthesias, which are markedly exacerbated by exposure to cold temperatures, and is a dose-limiting factor in the treatment of colorectal cancer.Oxalate is eliminated in a series of nonenzymatic conversions of oxaliplatin in infusion solutions or biological fluids.Elimination of oxalate from oxaliplatin has been suggested as one of the reasons for the development of acute neuropathy.In this study, we developed a high-performance liquid chromatography(HPLC)-based method to detect oxalate formation, and investigated the time dependent formation of oxalate in oxaliplatin diluted with infusion solutions.The results obtained showed that the amount of oxalate in the solution corresponded to 1.6% of oxaliplatin 8 h after oxaliplatin dilution with a 5% glucose solution. On the other hand, oxalate formation from oxaliplatin diluted with a saline solution was ten-fold higher than that from oxaliplatin diluted with the 5% glucose solution.Most patients who were intravenously injected with oxaliplatin experienced venous pain.As a preventive measure against venous pain, dexamethasone was added to the oxaliplatin injection.We measured the amount of oxalate formed in the dexamethasone-containing oxaliplatin injection diluted with a 5% glucose solution.The amount of oxalate formed when dexamethasone was added did not differ significantly from that formed when dexamethasone was not added.Thus, there are no clinical problems associated with the stability of oxaliplatin solutions.

Happiness Detected by the Emotion Cognition System Is Associated with Burnout in an Information Technology Products and Services Trading Company.

(1) Background: Although many previous studies have found an association between burnout and emotions, none have examined the association between emotions detected by an emotion cognition system and burnout. The purpose of this study is to examine the relationship between the emotions detected by the emotion cognition system and burnout among workers. We hypothesized that burnout survivors are less likely to express their emotions as facial expressions. (2) Methods: One hundred and forty-one workers at an Information Technology (IT) products and services trading company were asked to take facial images for three months when they started and left work and responded to a burnout questionnaire once a month. Microsoft Azure was used to detect their emotions. (3) Results: Hierarchical multiple regression analyses revealed that happiness in Period 1 was significantly and negatively associated with burnout at Time 2. This association was also observed after the various covariates were included. However, burnout at Time 3 was not significantly related to any emotions in Period 1. (4) Conclusions: Happiness, as detected by the emotion cognition system, was associated with burnout immediately afterward.

Mismatch negativity for speech sounds in temporal lobe epilepsy.

The mismatch negativity (MMN) is an electrophysiological trace of change detection, measured by electroencephalography (EEG), and is a reliable marker for pre-attentive auditory sensory memory. We used a phonetic oddball paradigm in patients with temporal lobe epilepsy (TLE) to elicit the MMN response at fronto-central sites and the mismatch positivity (MMP) response at mastoid sites. The MMN in 26 patients was compared with that of 26 age- and gender-matched healthy control participants. Electroencephalography responses were recorded during the presentation of speech sounds: the vowels 'a' and 'o' in alternation. Average waveforms were obtained for standard and deviant trials. We found that the MMP response at bilateral mastoid sites was reduced, whereas the MMN response at fronto-central sites did not change significantly. These results support the view that the MMN is generated by separable sources in the frontal and temporal lobes and that these sources are differentially affected by TLE.

Validity of intraoperative ECoG in the parahippocampal gyrus as an indicator of hippocampal epileptogenicity.

PURPOSE: Intraoperative electrocorticography (ECoG) in the parahippocampal gyrus is sometimes used as a substitute for intraoperative ECoG in the hippocampus. This study aimed to elucidate the validity of parahippocampal ECoG as an indicator of hippocampal epileptogenicity. METHODS: We retrospectively identified 10 patients with drug-resistant unilateral mesial temporal lobe epilepsy who achieved Engel class I or II after anteromedial temporal lobectomy. Intraoperative ECoG was recorded in the parahippocampal gyrus and hippocampal alveus at sevoflurane concentrations of 1.5-3.0%. We sought to identify the sevoflurane proconvulsant effects on spikes and high-frequency oscillations (HFOs) on spikes in the epileptogenic area. The number of spikes and number of HFOs superimposed on spikes were counted in ECoG recordings of the parahippocampal gyrus, hippocampal alveus, and lateral temporal lobe, and analyzed using two-way repeated-measures analysis of variance. RESULTS: The number of spikes and number of HFOs superimposed on spikes significantly increased as the sevoflurane concentration increased in both the hippocampal alveus and parahippocampal gyrus (spike, p < 0.001; ripple, p < 0.001; Fast ripple (FR), p < 0.001), and the pattern of increase was similar in these two areas. The number of spikes and number of HFOs on spikes were statistically higher in the hippocampal alveus than in the parahippocampal gyrus (spike, p = 0.004; ripple, p = 0.005; FR, p = 0.001). There were almost no spikes or HFOs on spikes in the lateral temporal lobe at sevoflurane concentrations in the range of 1.5-2.5%. CONCLUSIONS: Intraoperative ECoG in the parahippocampal gyrus can serve as an indicator of hippocampal epileptogenicity.

Questionnaire dataset: Attitude of epileptologists and obstetricians to pregnancy among women with epilepsy.

This data article presents supplementary material for our report "Role of obstetricians in promoting pregnancy-related knowledge among women with epilepsy in Japan" (Egawa et al. 2020). To provide more effective preconception counseling and perinatal care, we surveyed the attitude of epileptologists and obstetricians about pregnancy-related issues in women with epilepsy (WWE). Obstetricians said they needed information from epileptologists about seizure for management of WWE. Half of epileptologists did not feel the need to communicate with obstetricians before their patients' pregnancy; they only contacted obstetricians after their patients became pregnant, and they only referred patients to an obstetrician if requested by the patient.

Effects of sevoflurane anesthesia on intraoperative high-frequency oscillations in patients with temporal lobe epilepsy.

PURPOSE: This is a cross-sectional study without an unexposed group. We elucidated the effects of sevoflurane anesthesia on high-frequency oscillations (HFOs) to examine the usefulness of assessing intraoperative HFOs. METHODS: We recorded electrocorticography in seven patients with medication-resistant temporal lobe epilepsy (TLE) caused by unilateral hippocampal sclerosis who were seizure-free after temporal lobectomy. We analyzed the number of intraoperative spikes and HFOs on spikes in the epileptogenic parahippocampal gyrus and nonepileptogenic superior temporal gyrus with sevoflurane concentrations of 1.5%, 2.0%, 2.5%, and 3.0%. RESULTS: The number of spikes and HFOs in the epileptogenic area significantly increased with an increase in the sevoflurane concentration. In the nonepileptogenic area, spikes and HFOs did not significantly increase with increases in the sevoflurane concentration. However, 2.5% sevoflurane markedly induced spikes and ripples but no fast ripples (FRs) in one patient, and 3.0% sevoflurane induced marked increases in both ripples and FRs in two patients. CONCLUSIONS: The proconvulsant effect of sevoflurane on intraoperative HFOs in patients with TLE depends on the concentration. While HFOs induced by higher sevoflurane concentrations may be a useful biomarker for epileptogenic areas, careful interpretation is also needed because a higher sevoflurane concentration can also induce false-positive HFOs in nonepileptogenic areas.

Dynamic Granger-Geweke causality modeling with application to interictal spike propagation.

A persistent problem in developing plausible neurophysiological models of perception, cognition, and action is the difficulty of characterizing the interactions between different neural systems. Previous studies have approached this problem by estimating causal influences across brain areas activated during cognitive processing using structural equation modeling (SEM) and, more recently, with Granger-Geweke causality. While SEM is complicated by the need for a priori directional connectivity information, the temporal resolution of dynamic Granger-Geweke estimates is limited because the underlying autoregressive (AR) models assume stationarity over the period of analysis. We have developed a novel optimal method for obtaining data-driven directional causality estimates with high temporal resolution in both time and frequency domains. This is achieved by simultaneously optimizing the length of the analysis window and the chosen AR model order using the SURE criterion. Dynamic Granger-Geweke causality in time and frequency domains is subsequently calculated within a moving analysis window. We tested our algorithm by calculating the Granger-Geweke causality of epileptic spike propagation from the right frontal lobe to the left frontal lobe. The results quantitatively suggested that the epileptic activity at the left frontal lobe was propagated from the right frontal lobe, in agreement with the clinical diagnosis. Our novel computational tool can be used to help elucidate complex directional interactions in the human brain.

Vowel-speech versus pure-tone processing in healthy subjects.

To investigate the characteristics of speech perception, we evaluated the differences in mismatch negativity (MMN) between vowel change and frequency change. Additionally, we examined the effects of gender, age, and educational length on MMN. Forty healthy adults (21 females), who were native Japanese speakers, participated in the study. A Japanese vowel-speech pair (standard/a/vs. deviant/o/) and a pure-tone pair (standard 1000 Hz vs. deviant 1050 Hz) were constructed. MMN elicited by vowel-speech sounds was larger and earlier compared with pure-tone sounds. Larger and earlier MMNs for vowel-speech sounds than for pure-tone sounds suggest different processing of linguistically relevant information at the early stage in the auditory cortex. In conclusion, the factors influencing on MMN are different between vowel-speech sounds and pure-tone sounds.

Effect of protein and energy intakes on body composition in non-diabetic maintenance-hemodialysis patients.

This cross sectional study was performed to find the adequate amount and combination of dietary protein and energy for maintaining better nutritional status for stable non-diabetic maintenance hemodialysis (MHD) patients. The body composition including body fat, total body water, body cell mass and body protein were measured by multi-frequency bioelectrical impedance analysis in 200 stable MHD patients without diabetes (124 men, 76 women). Dietary energy intake (DEI) and dietary protein intake (DPI) were assessed by a brief self-administered diet history questionnaire (BDHQ), the DPI value being confirmed by calculating the normalized protein equivalent of total nitrogen appearance (nPNA). The nutritional status and the body composition were compared among 4 groups of patients in each gender that were divided by the combination of DEI and DPI; high energy (HE)/high protein (HP), HE/low protein (LP), low energy (LE)/HP and LE/LP groups. The mean DPI ranged between 1.17-1.23 and 0.89-0.95 g/kg IBW/d in the HP and LP groups, respectively for both genders, and the mean DEI was 35-37 and 24-25 kcal/kg IBW/d in HE and LE groups, respectively. BMI and serum albumin concentration were not different among the 4 groups. Body cell mass index (BCMI) was maintained in the HE groups regardless of DPI, and it was significantly higher in the HE/HP group than in the LE/LP group. Multiple regression analysis also showed that the BCMI was more greatly affected by DEI than DPI. These results indicated that a DPI of 0.89-0.95 g/kg IBW/d could be sufficient for maintaining BCMI, if DEI is kept over 35 kcal/kg IBW/d in stable non-diabetic MHD patients. This DPI level is lower than the recommended DPI proposed by dietary guidelines in the US and Japan.

Nutritional counseling regulates interdialytic weight gain and blood pressure in outpatients receiving maintenance hemodialysis.

Maintenance hemodialysis outpatients must limit salt and water intake to maintain electrolyte balance and blood pressure. In Kawashima Hospital, nationally registered dietitians provide hemodialysis patients with monthly nutritional counseling. We investigated whether nutritional counseling affects interdialytic weight gain (IDWG) and blood pressure. We investigated 48 hemodialysis patients whose monthly average IDWG ratio to dry weight exceeded 5.1% and who had not had a long-term hospital admittance of > 1 month. After the 48-month nutritional counseling period, the IDWG ratio had improved in 37 of the patients (77.1%), significantly decreasing from 6.0±0.7 to 5.3±0.9%. Estimated salt and water intake decreased significantly from 13.3±2.7 to 11.8±2.4 g/day and 2528±455 to 2332±410 ml/day, respectively. During the intervention period, normalized protein catabolic rate and body mass index did not change substantially. Pre-hemodialysis systolic and diastolic blood pressures had significantly decreased from 149±19 to 134±18 mmHg, and 82±13 to 75±10 mmHg for 48 months after study initiation, respectively. The dosage of antihypertensive drugs had significantly decreased in the group that experienced improvement in the IDWG ratio. Long-term nutritional counseling by nationally registered dietitians may improve the IDWG ratio and blood pressure of hemodialysis patients by decreasing their salt and water intake. J. Med. Invest. 64: 129-135, February, 2017.

Tetrahydrobiopterin improves aging-related impairment of endothelium-dependent vasodilation through increase in nitric oxide production.

Deficiency of tetrahydrobiopterin (BH4), an essential cofactor for nitric oxide (NO) synthase, decreases NO production and increases reactive oxygen species. The purpose of this study was to elucidate the effects of aging on endothelial function and to determine whether the degree of BH4 deficiency is related to aging and oxidative stress. We evaluated forearm blood flow (FBF) responses to acetylcholine (ACh), an endothelium-dependent vasodilator, and isosorbide dinitrate (ISDN), an endothelium-independent vasodilator, before and after co-infusion of BH4 (500 mg/min) in 37 healthy men (mean age, 41+/-18 yr; range, 19-81 yr). FBF was measured using strain-gauge plethysmograph. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and serum malondialdehyde-modified low-density lipoprotein (MDA-LDL) were measured as indices of oxidative stress. Both ACh and ISDN increased the FBF in a dose-dependent manner in all subjects. Co-infusion of BH4 resulted in a significant increase in ACh-induced vasodilation (from 22.3+/-6.7 to 30.1+/-7.5 mL/min/100 mL tissue, P<0.05). Aging was found to be significantly correlated with ACh-induced vasodilation (r=-0.47, P=0.006), urinary 8-OHdG (r=0.38, P=0.02), serum MDA-LDL (r=0.36, P=0.02), and the change in ACh-induced vasodilation after co-infusion of BH4 (r=0.45, P=0.007). The FBF response to ISDN did not correlate with any parameters. Infusion of N(G)-monomethyl-L-arginine, an NO synthase inhibitor, abolished the BH4-induced enhancement of forearm vasorelaxation evoked by ACh. The increase in FBF after ISDN was not altered by BH4. These findings suggest that a deficiency of BH4 may be involved in the pathogenesis of disturbances in endothelium-dependent vasodilation related to aging through decrease in NO production and increase in oxidative stress.

Smoking, endothelial function, and Rho-kinase in humans.

OBJECTIVE: Smoking is associated with endothelial dysfunction and activated Rho-kinase in vascular smooth muscle cells (VSMCs) in humans. The purpose of this study was to elucidate the relationship between endothelial function and Rho-kinase activity in forearm VSMCs in healthy young men. METHODS AND RESULTS: We evaluated the forearm blood flow (FBF) responses to acetylcholine (ACh), fasudil, a Rho-kinase inhibitor, and sodium nitroprusside (SNP) in male smokers (n=10) and nonsmokers (n=14). FBF was measured by using a strain-gauge plethysmography. The vasodilatory effect of ACh was significantly smaller in smokers than that in nonsmokers. The vasodilatory effect of fasudil was significantly greater in smokers than that in nonsmokers. The vasodilatory effects of SNP in the 2 groups were similar. There was a significant correlation between the maximal FBF response to fasudil and that to ACh (r=-0.67; P<0.01). There was no significant correlation between the maximal FBF response to fasudil and that to SNP. The intra-arterial coinfusion of fasudil significantly increased the FBF response to ACh in smokers but not in nonsmokers. There were no significant differences between FBF response to fasudil alone and that in combination with NG-monomethyl-L-arginine in smokers and in nonsmokers. The intra-arterial coinfusion ascorbic acid did not alter the FBF response to fasudil in both groups. CONCLUSIONS: These findings suggest that smoking is involved in not only endothelial dysfunction but also activation of Rho-kinase in VSMCs in forearm circulation, and that there is a significant correlation between endothelial function and Rho-kinase activity in VSMCs.