Association between flexibility activity and blood-pressure change among older adults in Japan: A 5-year longitudinal study.

This longitudinal study examined the relationship between flexibility-activity and blood-pressure (BP) change among older adults in Japan. Our study included 452 older adults who took part in our survey in both 2012/2013 and 2017/2018. The seated systolic blood pressure (SBP) and diastolic BP (DBP) were measured both at baseline and at the 5 years follow-up. The frequencies of the different physical activities at baseline were assessed using a questionnaire. A generalized linear mixed model was used to estimate the non-standardized coefficient (B) of BP change associated with flexibility activity, after adjustments for sex, age, body mass index, smoking status, alcohol consumption, antihypertensive medication use, history of heart disease, walking time, and muscle-strengthening activity as a fixed-effect, and area of residence as a random-effect. Higher flexibility-activity frequency was significantly associated with reduced SBP (B = -0.77 [95% confidence intervals = -1.36, -0.18], p for linear trend = 0.01, p for quadratic trend = 0.85) and DBP (-0.33 [-0.71, 0.05], p for linear trend = 0.09, p for quadratic trend = 0.04). Engaging in flexibility activity for 3 days per week was significantly associated with a reduction in DBP (B = -4.16, 95% CI [-7.53, -0.79], p = 0.02) compared with that in the reference group (0 days per week). Interaction tests were not significant between basic variables (sex, age, BMI, and antihypertensive medication) and flexibility. In conclusion, higher flexibility activity frequency was associated with a reduction in BP in older adults. Future longitudinal and interventional studies should examine the effects of flexibility activity on cardiovascular disease prevention.

Associations between dairy consumption and the physical function in Japanese community-dwelling older adults: The Shimane CoHRE study.

OBJECTIVES: We investigated sex differences in the associations between dairy consumption and the physical function among community-dwelling older adults. METHODS: Six hundred and fifty-six older adults (75.6 ± 6.4 years old) participated in this study. Dairy consumption (5-item Likert score) and the physical function (gait speed, handgrip strength, and skeletal muscle mass) were measured. The linear and quadratic associations between dairy consumption and the physical function measures were examined by a multiple linear regression analysis adjusted for covariates. RESULTS: Among women, an increased dairy consumption was significantly linearly associated with greater hand-grip strength and faster gait speed (both p<0.05) after adjusting for covariates. Among men, dairy consumption was not associated with the physical function measures. Dairy consumption was not associated with the muscle mass in either sex. CONCLUSIONS: Increased dairy consumption was associated with a superior physical function in older women.

Association of lysophosphatidic acid molecules with liver fibrosis: different roles indicated.

Lysophosphatidic acid is composed of lysophosphatidic acid (LPA) molecules with varied chemical forms. The present cross-sectional study was conducted to investigate the associations of various LPA molecules with liver fibrosis. Forty-six patients affected by various types of liver disease who underwent an ultrasound-guided liver biopsy were recruited for this study. Liver fibrosis was evaluated using histological grading, as well as shear wave velocity (Vs) and serum level of type IV collagen 7S (T4c7s). Serum levels of LPA molecules were determined using liquid-chromatography tandem mass-spectrometry (LC-MSMS). Total LPA showed a significant positive association with fibrosis severity evaluated based on histological grading, Vs, and T4c7s used as parameters, following adjustment for other confounding factors, including disease type, age, gender, body mass index, and high-sensitivity C-reactive protein. This association was replicated when 16:0-LPA was substituted for total LPA. In contrast, when 20:4-LPA was substituted for total LPA, no significant association with liver fibrosis was observed. In conclusion, the degree of association varied among the different LPA molecule chemical forms, suggesting different pathophysiological roles of individual LPA molecules, although total LPA concentration was shown to be associated with liver fibrosis.

Defective Function of the Blood-Brain Barrier in a Stroke-Prone Spontaneously Hypertensive Rat: Evaluation in an In Vitro Cell Culture Model.

The blood-brain barrier (BBB) comprises three cell types: brain capillary endothelial cells (BECs), astrocytes, and pericytes. Abnormal interaction among these cells may induce BBB dysfunction and lead to cerebrovascular diseases. The stroke-prone spontaneously hypertensive rat (SHRSP) harbors a defective BBB, so we designed the present study to examine the role of these three cell types in a functional disorder of the BBB in SHRSP in order to elucidate the role of these cells in the BBB more generally. To this end, we employed a unique in vitro model of BBB, in which various combinations of the cells could be tested. The three types of cells were prepared from both SHRSPs and Wistar Kyoto rats (WKYs). They were then co-cultured in various combinations to construct in vitro BBB models. The barrier function of the models was estimated by measuring transendothelial electrical resistance and the permeability of the endothelial monolayer to sodium fluorescein. The in vitro models revealed that (1) BECs from SHRSPs had an inherent lower barrier function, (2) astrocytes of SHRSPs had an impaired ability to induce barrier function in BECs, although (3) both pericytes and astrocytes of SHRSPs and WKYs could potentiate the barrier function of BECs under co-culture conditions. Furthermore, we found that claudin-5 expression was consistently lower in models that used BECs and/or SHRSP astrocytes. These results suggested that defective interaction among BBB cells-especially BECs and astrocytes-was responsible for a functional disorder of the BBB in SHRSPs.

Milk Fermented with Mushrooms Prevents Stroke in the Stroke-Prone Spontaneously Hypertensive Rats Independently of Blood Pressure.

OBJECTIVES: In a previous study, a mushroom was shown to digest milk protein to a mixture of oligopeptides and free amino acids. The aim of this study was to examine effects of this mixture, i.e., mushroom-fermented milk, on blood pressure and stroke susceptibility in the stroke-prone spontaneously hypertensive rats (SHRSP). MATERIALS AND METHODS: Rats were fed mushroom-fermented milk with or without 1 % salt water. Blood pressure was monitored either by the tail-cuff method or the telemetry system. Symptoms of stroke were examined every day to determine the stroke latency. RESULTS: Mushroom-fermented milk at 120 mg/Kg BW/day (estimated as a peptides/amino acids content) did not ameliorate hypertension in SHRSP. In contrast, mushroom-fermented milk significantly improved stroke susceptibility under salt-loading. The effects were replicated using milk fermented with three different mushrooms. To elucidate the effective components in mushroom-fermented milk, spermidine (3 mM), one of major components of mushroom-fermented milk, and a mixture of amino acids (0.8 g/L) was examined, both of which showed no significant effects on stroke susceptibility. Intake of mushroom-fermented milk did not affect sodium content significantly either in feces or in urine of the rats given 1% salt water. This observation indicated sodium absorption by the digestive system was not inhibited by intake of mushroom-fermented milk. CONCLUSION: Despite that the mechanisms were not elucidated, intake of mushroom-fermented milk effectively prevented stroke in SHRSP. Mushroom-fermented milk would be a new candidate for a supplemental nutrient supporting the cardiovascular health.

Patient satisfaction and loyalty in Japanese primary care: a cross-sectional study.

BACKGROUND: This study aimed to explore associations between various elements of primary care, patient satisfaction, and loyalty. METHODS: This cross-sectional study used a modified version of the Primary Care Assessment Tool (PCAT), which was adapted for Japan. We distributed the PCAT questionnaire to patients aged 20 years or older at five rural primary care centres in Japan. We confirmed the validity and reliability of the measure for our study. Next, we examined which elements of primary care were related to patient satisfaction and loyalty using Spearman's correlation and structural equation modelling. RESULTS: Of 220 eligible patients, 206 participated in this study. We developed nine component scales: first contact (regular access), first contact (urgent access), longitudinality, coordination, comprehensiveness (variety of care), comprehensiveness (risk prevention), comprehensiveness (health promotion), family-centeredness, and community orientation. Longitudinality and first contact (urgent access) were related with patient satisfaction. Longitudinality, first contact (regular access), and family-centeredness were related to patient loyalty. In the structural equation modelling analysis, two variables were significantly related to loyalty, namely a combined variable including longitudinality and first contact (regular access), along with family-centeredness. CONCLUSIONS: While a patient satisfaction model could not be distilled from the data, longitudinality, first contact (urgent access), and family-centeredness were identified as important elements for the cultivation of patient loyalty. This implies that primary care providers need to develop a deep understanding of patients' contexts and concerns and pay attention to their level of access to cultivate greater patient loyalty.

Pathophysiological significance of Stim1 mutation in sympathetic response to stress and cardiovascular phenotypes in SHRSP/Izm: In vivo evaluation by creation of a novel gene knock-in rat using CRISPR/Cas9.

Genetic approach using rat congenic lines between SHRSP/Izm and WKY/Izm identified stromal interaction molecule 1 (Stim1), an essential component of store-operated Ca2+ entry (SOCE), as a promising candidate gene responsible for the exaggerated sympathetic response to stress in SHRSP. Since SHRSP has a nonsense mutation in Stim1 resulting in the expression of a truncated form of STIM1 that caused reduction of SOCE activity in primary cultured cerebral astrocytes, we created SHRSP/Izm knocked-in with the wild-type Stim1 (KI SHRSP) by the CRISPR/Cas9 method to investigate whether the functional recovery of STIM1 would mitigate sympatho-excitation to stress in vivo in SHRSP. No potential off-target nucleotide substitutions/deletions/insertions were found in KI SHRSP. Western blotting and fluorescent Ca2+ imaging of astrocytes confirmed wild-type STIM1 expression and restored SOCE activity in astrocytes from KI SHRSP, respectively. Blood pressure (BP) measured by the tail-cuff method at 12, 16, and 20 weeks of age did not significantly differ between SHRSP and KI SHRSP, while the heart rate of KI SHRSP at 16 and 20 weeks of age was significantly lower than that of age-matched SHRSP. Unexpectedly, the sympathetic response to stress (evaluated with urinary excretion of norepinephrine under cold stress and BP elevation under cold/restraint stress) did not significantly differ between SHRSP and KI SHRSP. The present results indicated that the functional deficit of STIM1 was not a genetic determinant of the exaggerated sympathetic response to stress in SHRSP and that it would be necessary to explore other candidates within the congenic fragment on chromosome 1.

Fast food outlets, physical activity facilities, and obesity among adults: a nationwide longitudinal study from Sweden.

BACKGROUND: While neighborhood deprivation is a well-known predictor of obesity, the mechanisms behind this association are unclear and these are important to clarify before designing interventions focusing on modifiable neighborhood environmental factors in order to reduce obesity risk. OBJECTIVES: This study examined the longitudinal association between availability of fast-food outlets and physical activity facilities and the risk of obesity among adults. METHODS: This study used multiple national register data from Sweden. During the 11-year follow-up period between 2005 and 2015, data from 1,167,449 men and 542,606 women, aged 20-55 years, were accessible for inclusion in this analysis. Incidence of obesity was identified based on a diagnosis of obesity during the follow-up period derived from clinical register data. Neighborhood availability of fast-food outlets and physical activity facilities were assessed in 2005 and Cox regression was used in the statistical analysis. Individual socio-demographic factors and neighborhood deprivation were used as covariates. RESULTS: There were no meaningful associations between neighborhood fast-food outlets or physical activity facilities and obesity in men or women. Neighborhood deprivation was, however, consistently and strongly associated with incidence of obesity in both men and women. CONCLUSIONS: Availability of fast-food outlets and lack of physical activity facilities appear unlikely to cause obesity in Swedish adults. Other potentially modifiable environmental factors within specific social and cultural settings that may influence obesity risk should be examined in future studies.

Prevalence and Correlates of Physical Activity Among Children and Adolescents: A Cross-Sectional Population-Based Study of a Rural City in Japan.

BACKGROUND: Although moderate-to-vigorous physical activity (MVPA) has multiple health benefits, current participation in recommended MVPA level and its determinants among Japanese children and adolescents remain unclear. Therefore, this cross-sectional study investigated the prevalence of meeting recommended MVPA level and its correlates among Japanese children and adolescents. METHODS: Using the Japanese version of the World Health Organization (WHO) Health Behaviour in School-aged Children survey questionnaire, we confirmed the prevalence of meeting recommended MVPA level in all primary schools (PS) and junior high schools (JHS) in Unnan City, Japan. We evaluated its association with school grade, gender, body weight status, screen time, consumption of breakfast, physical activity (PA) preference, and population density using Poisson regression. RESULTS: We found that 20.1% of the 1,794 students (9-15 years old) met the WHO recommendation. Meeting recommended MVPA level was significantly associated with being in the sixth grade of PS (prevalence ratio [PR] 0.57; 95% confidence interval [CI], 0.39-0.84) and first (PR 1.52; 95% CI, 1.16-1.99), second (PR 1.45; 95% CI, 1.10-1.90), and third grade of JHS (PR 0.40; 95% CI, 0.26-0.62) (vs fourth grade of PS); being a boy (PR 1.33; 95% CI, 1.12-1.59) (vs girl); liking PA (PR 3.72; 95% CI, 2.22-6.22) (vs dislike); and belonging to a medium-population-density (PR 0.73; 95% CI, 0.61-0.88) or low-population-density area (PR 0.67; 95% CI, 0.48-0.94) (vs high-population-density area). CONCLUSIONS: About 20% of Japanese children and adolescents engaged in the recommended MVPA level. MVPA was associated with grade, gender, preference for PA, and population density.

Neighborhood environment and muscle mass and function among rural older adults: a 3-year longitudinal study.

BACKGROUND: Sarcopenia, resulting from loss of muscle mass and function, is highly prevalent in the ageing societies and is associated with risk of falls, frailty, loss of independence, and mortality. It is important to identify environmental risk factors, so that evidence-based interventions to prevent sarcopenia can be implemented at the population level. This study aimed to examine the potential effect of several objectively measured neighborhood environmental factors on longitudinal change of muscle mass and function among older adults living in rural Japanese towns where the population is ageing. METHODS: This study was based on data from the Shimane CoHRE Study conducted by the Center for Community-based Healthcare Research and Education (CoHRE) at Shimane University in 3 rural towns in the Shimane Prefecture, Japan. Subjects older than 60 years, who participated in an annual health examination in 2016 and any follow-up years until 2019, i.e., 4 possible time points in total, were included (n = 2526). The skeletal muscle mass index (SMI) and grip strength were assessed objectively for each year as a measure of muscle mass and function, respectively. Neighborhood environmental factors, i.e., hilliness, bus stop density, intersection density, residential density, and distance to a community center were measured by geographic information systems (GIS). Linear mixed models were applied to examine the potential effect of each neighborhood environmental factor on the change of SMI and grip strength over time. RESULTS: Males living far from community centers had a less pronounced decline in SMI compared to those living close to community centers. Females living in areas with higher residential density had a less pronounced decline in grip strength compared to those living in areas with lower residential density. CONCLUSIONS: Neighborhood environmental factors had limited effects on change of SMI and grip strength among rural older adults within the 3 years follow up. Further long-term follow up studies are necessary by also taking into account other modifiable neighborhood environmental factors.

Additive Effect of Physical Activity and Sedentary Time on Depressive Symptoms in Rural Japanese Adults: A Cross-Sectional Study.

BACKGROUND: Previous studies have reported an additive effect of moderate-to-vigorous physical activity (MVPA) and sedentary time (ST) on depressive symptoms. However, no studies have been conducted in rural community settings. This cross-sectional study investigated whether the additive effect of MVPA and ST was associated with depressive symptoms in rural Japanese adults. METHODS: We identified 2,814 participants from health examinations conducted in Shimane, rural Japan, in 2012 and analyzed data from 1,958 participants. We assessed depressive symptoms using the Zung Self-Rating Depression Scale and measured the total time spent on MVPA and ST using a Japanese short version of the International Physical Activity Questionnaire. Poisson regression analysis examined the prevalence ratios (PR) of depressive symptoms in nine category combinations of MVPA level (no, insufficient, or sufficient MVPA) and ST level (high, moderate, or low ST). RESULTS: A total of 117 (6.0%) participants had depressive symptoms. Compared with the reference category (no MVPA/high ST), multivariate analysis showed that the likelihood of depressive symptoms was significantly lower in the sufficient MVPA/low ST category (PR 0.23; 95% confidence intervals [CI], 0.08-0.66), insufficient MVPA/low ST category (PR 0.37; 95% CI, 0.16-0.86), and insufficient MVPA/moderate ST category (PR 0.39; 95% CI, 0.17-0.90). CONCLUSION: Analysis of the additive effect of MVPA and ST showed that the combinational category of sufficient MVPA and low ST had the lowest prevalence of depressive symptoms in rural Japanese adults. Moderate ST and low ST showed significantly lower likelihoods of depressive symptoms, regardless of insufficient MVPA.

Hilly neighborhoods are associated with increased risk of weight gain among older adults in rural Japan: a 3-years follow-up study.

BACKGROUND: Neighborhood environments have been regularly associated with the weight status. Although the evidence is mostly limited to adults residing in western urban settings, the weight status of older adults living in rural areas is also assumed to be significantly affected by their neighborhood environments. This study aimed to identify environmental attributes specific to rural areas that could affect the risk of longitudinal weight gain among older adults (≥ 65 years) in Japan. METHODS: We examined five environmental attributes, i.e., land slope, public transportation accessibility, residential density, intersection density, and the availability of parks and recreational centers, measured by the geographic information system. Our analysis was based on 714 subjects participated in Shimane Community-based Healthcare Research and Education study in 2012 and 2015. Multinomial logistic regression model was conducted to examine the association between each neighborhood environmental attribute and weight change status (gain, loss and unchanged). RESULTS: We observed a significant increase in the risk of weight gain as the steepness of the neighborhood land slope increased. There was no significant association between other environmental attributes and risk of weight gain as well as weight loss among older adults. CONCLUSION: Living in hilly neighborhoods was associated with increased risk of weight gain among rural Japanese older adults. Future research should consider region-specific environmental attributes when investigating their effect on older adults' weight status.

Height loss but not body composition is related to low back pain in community-dwelling elderlies: Shimane CoHRE study.

BACKGROUND: Low back pain (LBP) is a common complaint in the elderly Japanese population. Although previous studies showed that height loss was associated with LBP, it remains unclear whether LBP is associated with body composition. The objective of the present study was to investigate whether body composition and physical characteristics, including height loss, were associated with LBP. METHODS: The present study is retrospectively registered, and the participants were 2212 community-dwelling Japanese people aged over 60 years who participated in the Shimane CoHRE study in 2016. We investigated the presence of LBP, body composition parameters (muscle, fat, body weight, and bone mass), physical characteristics (body height and height loss), chronic diseases, history of fall, smoking, and drinking habits. We examined the relationships of body composition parameters and physical characteristics with point prevalence of LBP using multivariate logistic regression. RESULTS: The point prevalence of LBP was 43.2% in women and 39.5% in men. Logistic regression models showed that body height and body composition were not significantly associated with LBP; however, height loss was associated significantly with LBP in women and men (OR: 1.14, 95% CI: 1.08-1.20 and OR: 1.13, 95% CI: 1.06-1.21, respectively). Hypertension (OR: 1.32, 9 5% CI: 1.04-1.69) and chronic heart disease (OR: 1.57, 95% CI: 1.01-2.43) in women and history of fall (OR: 1.70, 95% CI: 1.13-2.56) and cerebrovascular disease (OR: 1.88, 95% CI: 1.05-3.34) in men were significantly associated with LBP. However, body composition was not associated with LBP in either gender. CONCLUSIONS: The present study demonstrated that height loss, but not body composition, was related to LBP in community-dwelling elderly people. To elucidate the cause of LBP, it is important to consider the relationship with height loss.

Development of the Japanese version of the general practice assessment questionnaire: measurement of patient experience and testing of data quality.

BACKGROUND: Physicians' interpersonal performance is critical in medical practice, especially primary care practice. The General Practice Assessment Questionnaire (GPAQ) was developed in the United Kingdom to evaluate the quality of primary care from the viewpoint of patients. This questionnaire highlights the evaluation of interpersonal skills and interactions between physicians and patients. Though several other tools also exist to evaluate primary care quality, the GPAQ has several distinctive evaluation items, covering receptionists, access to primary care, and enablement (patients' understanding of self-care and of their own health after consultation). Our purpose was to develop and validate a Japanese version of the GPAQ. METHODS: This cross-sectional study tested the validity and reliability of the Japanese version of the questionnaire. We translated the original GPAQ into Japanese and assessed its reliability and validity among patients aged ≥20 years at five rural primary care centres located in Shimane and Okayama prefectures, Japan. We also examined its internal reliability using Cronbach's alpha coefficient and construct validity-including item-scale correlations, item-other scale correlations, and inter-scale correlations. Moreover, we examined correlations between each score and overall satisfaction using Spearman's correlation coefficient for criterion-related validity. RESULTS: The translated version of the GPAQ was administered, and we received 252 responses (mean age: 68 ± 12.3 years, male: 42.9%); all data were analysed. The translated questionnaire showed good reliability and validity, with Cronbach's alphas ranging from 0.79-0.92 for all scales, and satisfactory item-scale, item-other scale, and inter-scale correlations. Correlations with overall satisfaction were strong (Spearman's correlation coefficients: 0.31-0.38) for all scales except 'continuity of care'. CONCLUSIONS: The Japanese version of the GPAQ was acceptable, reliable, and valid. This could be a useful instrument to evaluate key areas of primary care performance in Japan, particularly physicians' communication skills. Further work is required to evaluate its utility in urban areas.

Arginine vasopressin altered the expression of monocarboxylate transporters in cultured astrocytes isolated from stroke-prone spontaneously hypertensive rats and congenic SHRpch1_18 rats.

BACKGROUND: Astrocytes support a range of brain functions as well as neuronal survival, but their detailed relationship with stroke-related edema is not well understood. We previously demonstrated that the release of lactate from astrocytes isolated from stroke-prone spontaneously hypertensive rats (SHRSP/Izm) was attenuated under stroke conditions. The supply of lactate to neurons is regulated by astrocytic monocarboxylate transporters (MCTs). The purpose of this study was to examine the contributions of arginine vasopressin (AVP) and/or hypoxia and reoxygenation (H/R) to the regulation of MCTs and neurotrophic factor in astrocytes obtained from SHRSP/Izm and congenic SHRpch1_18 rats. METHODS: We compared AVP-induced lactate levels, MCTs, and brain-derived neurotrophic factor (BDNF) in astrocytes isolated from SHRSP/Izm, SHRpch1_18, and Wistar Kyoto rats (WKY/Izm). The expression levels of genes and proteins were determined by PCR and Western blotting (WB). RESULTS: The production of lactate induced by AVP was increased in astrocytes from all three strains. However, the levels of lactate were lower in SHRSP/Izm and SHRpch1_18 animals compared with the WKY/Izm strain. Gene expression levels of Slc16a1, Slc16a4, and Bdnf were lowered by AVP in SHRSP/Izm and SHRpch1_18 rats compared with WKY/Izm. The increase of MCT4 that was induced by AVP was blocked by the addition of a specific nitric oxide (NO) chelator, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO). Furthermore, AVP increased the expression of iNOS and eNOS proteins in WKY/Izm and SHRSP/Izm rat astrocytes. However, the iNOS expression levels in SHRSP astrocytes differed from those of WKY/Izm astrocytes. The increase of MCT4 protein expression during AVP treatment was blocked by the addition of a specific NF-kB inhibitor, pyrrolidine dithiocarbamate (PDTC). The induction of MCT4 by AVP may be regulated by NO through NF-kB. CONCLUSIONS: These results suggest that the expression of MCTs mediated by AVP may be regulated by NO. The data suggest that AVP attenuated the expression of MCTs in SHRSP/Izm and SHRpch1_18 astrocytes. Reduced expression of MCTs may be associated with decreased lactate production in SHRSP.

NADPH Oxidase-Related Pathophysiology in Experimental Models of Stroke.

Several experimental studies have indicated that nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox) exert detrimental effects on ischemic brain tissue; Nox-knockout mice generally exhibit resistance to damage due to experimental stroke following middle cerebral artery occlusion (MCAO). Furthermore, our previous MCAO study indicated that infarct size and blood-brain barrier breakdown are enhanced in mice with pericyte-specific overexpression of Nox4, relative to levels observed in controls. However, it remains unclear whether Nox affects the stroke outcome directly by increasing oxidative stress at the site of ischemia, or indirectly by modifying physiological variables such as blood pressure or cerebral blood flow (CBF). Because of technical problems in the measurement of physiological variables and CBF, it is often difficult to address this issue in mouse models due to their small body size; in our previous study, we examined the effects of Nox activity on focal ischemic injury in a novel congenic rat strain: stroke-prone spontaneously hypertensive rats with loss-of-function in Nox. In this review, we summarize the current literature regarding the role of Nox in focal ischemic injury and discuss critical issues that should be considered when investigating Nox-related pathophysiology in animal models of stroke.

A nonsense mutation of Stim1 identified in stroke-prone spontaneously hypertensive rats decreased the store-operated calcium entry in astrocytes.

We previously identified a nonsense mutation in the stromal interaction molecule-1 (Stim1) resulting in expression of a truncated STIM1 in the stroke-prone spontaneously hypertensive rat (SHRSP). In this study, we evaluated activity of the store-operated Ca(2+)-entry (SOCE) regulated by STIM1 to clarify putative functional abnormalities of the truncated STIM1. As a result, reduced SOCE activity resulting in suppression of cyclooxygenase-2 expression induced by SOCE was found in cultured astrocytes with the truncated STIM1 when compared with those with the wild-type. Our results indicated that the truncated STIM1 impaired Ca(2+) signaling regulated by SOCE and that the impaired SOCE activity might be responsible for pathological phenotypes in SHRSP.

Different effects of arginine vasopressin on high-mobility group box 1 expression in astrocytes isolated from stroke-prone spontaneously hypertensive rats and congenic SHRpch1_18 rats.

Stroke-prone spontaneously hypertensive rats (SHRSP/Izm) develop severe hypertension and astrocytic oedema following ischaemic stimulation. During ischaemic stress high-mobility group box 1 (Hmgb1) expression in astrocytes is induced, and subsequently potentiates deterioration of the brain due to ischaemic injury, which manifests as both cerebral inflammation and astrocytic oedema. Arginine vasopressin (AVP) induces brain injury and increases astrocytic swelling. After stroke, Hmgb1 and peroxiredoxin (Prx) are released at different times and activate macrophages in the brain via Toll-like receptors (Tlr2s). The purpose of this study was to examine whether AVP and/or hypoxia and reoxygenation (H/R) contribute to Hmgb1 regulation following ischaemic stroke. Thus, Hmgb1, Prx2 and Tlr2 expression levels in astrocytes isolated from Wistar Kyoto rats (WKY/Izm), spontaneously hypertensive rats (SHR/Izm), SHRSP/Izm and congenic rat strain SHRpch1_18 treated with AVP and/or H/R were compared. Gene and protein expression levels were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time quantitative PCR, and Western blot. mRNA expression of Hmgb1, Prx2 and Tlr2 induced by AVP was dose-dependent, and Hmgb1 and Prx2 expression was higher in SHR/Izm, SHRSP/Izm and SHRch1_18 than in WKY/Izm. Tlr2 expression with AVP was reduced in SHR/Izm compared to WKY/Izm. In SHRpch1_18, Hmgb1 expression increased after AVP plus H/R. AVP-modulated expression of Hmgb1 protein was reduced by the addition of the antioxidant N-acetylcysteine (NAC). These results suggest that oxidative stress by AVP enhanced expression of Hmgb1, Prx2 and Tlr2 in astrocytes. We hypothesize that regulation of Hmgb1 by AVP during H/R might be related to induction of inflammation and stroke in SHRSP/Izm and SHRpch1_18 rats.

Depression, stroke and gender: evidence of a stronger association in men.

BACKGROUND/AIMS: Depression is associated with an increased risk for stroke. The aim of this study was to examine whether demographic and socioeconomic factors modify this association. METHODS: This follow-up study comprised 137 305 men and 188 924 women aged ≥30 years from a nationwide sample of primary healthcare centres in Sweden. We identified 4718 first-ever stroke cases (2217 men and 2501 women) during the follow-up period (2005-2007). Multilevel logistic regression models were used to calculate ORs and examine interactions in order to determine whether the association between depression and stroke differs by demographic or socioeconomic factors. RESULTS: Depression was associated with significantly greater odds of stroke after adjustment for potential confounding factors (OR=1.22, 95% CI 1.08 to 1.38). Interaction tests showed that the effect of depression on stroke was higher in men compared with women (the difference in OR between men and women was 1.30, 95% CI 1.01 to 1.68), that is, the association between depression and stroke was modified by gender. CONCLUSIONS: Our findings suggest that the depression-stroke association is modified by gender. Further studies are required to examine the underlying mechanisms in men and women.