Spermine Suppresses Adipocyte Differentiation and Exerts Anti-Obesity Effects In Vitro and In Vivo.

Endogenous polyamines such as putrescine (Put), spermidine (Spd), and spermine (Spm) affect adipocyte differentiation. In this study, we investigated the effect of exogenously supplemented polyamines on mouse adipocyte differentiation and anti-obesity actions in vitro and in vivo. The preadipocyte cell line, 3T3-L1, was cultured with Put, Spd, or Spm, and lipid accumulation in the cells was measured by Oil Red O staining. Lipid accumulation was significantly suppressed by Spm. Suppression of CCAAT/enhancer binding protein α mRNA by Spm suggested that the decreased lipid accumulation was due to delaying the cell differentiation. The body weight and fat of obese mice induced with a high-fat diet were reduced by oral ingestion of Spm. In conclusion, oral supplementation of Spm has the ability to prevent obesity through inhibition of adipocyte differentiation.

Are Preschoolers' Neurobiological Stress Systems Responsive to Culturally Relevant Contexts?

Adults are biologically responsive to context, and their responses to particular situations may differ across cultures. However, are preschoolers' biological systems also responsive to situational contexts and cultures? Here, we show that children's neurobiological stress responses, as indexed by salivary cortisol, are activated and responsive to psychosocial stressors relevant to their sociocultural emphases. By examining cortisol changes across different contexts among 138 preschoolers living in the United States, China, and Japan, we found that an achievement-related stressor elicited an increased cortisol response among Chinese preschoolers, whereas interpersonal-related stressors elicited an increased cortisol response among Japanese preschoolers. By contrast, U.S. preschoolers showed decreased cortisol responses after these stressors but consistently higher levels of anticipatory responses to separation at the beginning of each session. Our findings suggest that children's neurobiological stress systems may be a critical biological mechanism allowing societal-level cultural phenomena to be embodied in individual-level responses, even among preschoolers.

Emotion expression and regulation in three cultures: Chinese, Japanese, and American preschoolers' reactions to disappointment.

There are strong cultural norms for how emotions are expressed, yet little is known about cultural variations in preschoolers' outward displays and regulation of disappointment. Chinese, Japanese, and American preschoolers' (N = 150) displays of emotion to an undesired gift were coded across both social and nonsocial contexts in a "disappointing gift" paradigm. Generalized estimating equations revealed that, regardless of culture, when children received a disappointing gift, they showed more positive expressions of emotion ("fake smile") in social contexts (in the presence of unfamiliar and familiar examiners) relative to when they were alone, suggesting that preschool-aged children are able to mask their disappointment with positive displays. However, children's emotion expressions varied across both cultures and contexts. American children were more positively and negatively expressive than Japanese children and were more negatively expressive than Chinese children. Chinese and Japanese preschoolers verbally reported more negative emotions but showed more neutral expressions than American preschoolers when receiving the disappointing gift. In addition, across different contexts of the task, there were subtle differences in how Chinese and Japanese children regulated their emotional expressions, with Chinese children showing similar levels of neutral expressions (e.g., "poker face") across different contexts in the task. Thus, our findings highlight the importance of understanding cultural meanings and practices underlying emotion development during early childhood.

Cultural and life style practices associated with low inflammatory physiology in Japanese adults.

Japan is an exceptionally healthy East Asian country with extended longevity. In addition, the typical levels of several proinflammatory proteins, including both C-reactive protein (CRP) and interleukin-6 (IL-6), are often reported to be low when compared to American and European populations. This analysis determined if blood levels of CRP and IL-6 were associated with 4 cultural practices reflective of Japanese behavior and customs -- drinking tea, eating seafood, consuming vegetables, and partaking in relaxing baths regularly - among 382 adults living in Tokyo. Regression models controlled for demographic factors, adiposity (BMI), physical exercise, smoking, alcohol use, and chronic illness (e.g., diabetes). Consuming a Japanese diet was associated with significantly lower CRP and IL-6 levels. More frequent bathing was associated with lower IL-6, but not specifically predictive of low CRP. This study has confirmed prior evidence for low inflammatory activity in Japanese adults and its association with several behavioral practices common in Japan.

Culture and personality revisited: Behavioral profiles and within-person stability in interdependent (vs. independent) social orientation and holistic (vs. analytic) cognitive style.

OBJECTIVE: We test the proposition that both social orientation and cognitive style are constructs consisting of loosely related attributes. Thus, measures of each construct should weakly correlate among themselves, forming intraindividually stable profiles across measures over time. METHOD: Study 1 tested diverse samples of Americans (N = 233) and Japanese (N = 433) with a wide range of measures of social orientation and cognitive style to explore correlations among these measures in a cross-cultural context, using demographically heterogeneous samples. Study 2 recruited a new sample of 485 Americans and Canadians and examined their profiles on measures of social orientation and cognitive style twice, one month apart, to assess the stability of individual profiles using these variables. RESULTS: Despite finding typical cross-cultural differences, Study 1 demonstrated negligible correlations both among measures of social orientation and among measures of cognitive style. Study 2 demonstrated stable intraindividual behavioral profiles across measures capturing idiosyncratic patters of social orientation and cognitive style, despite negligible correlations among the same measures. CONCLUSION: The results provide support for the behavioral profile approach to conceptualizing social orientation and cognitive style, highlighting the need to assess intraindividual stability of psychological constructs in cross-cultural research.

Expression of anger and ill health in two cultures: an examination of inflammation and cardiovascular risk.

Expression of anger is associated with biological health risk (BHR) in Western cultures. However, recent evidence documenting culturally divergent functions of the expression of anger suggests that its link with BHR may be moderated by culture. To test this prediction, we examined large probability samples of both Japanese and Americans using multiple measures of BHR, including pro-inflammatory markers (interleukin-6 and C-reactive protein) and indices of cardiovascular malfunction (systolic blood pressure and ratio of total to HDL cholesterol). We found that the link between greater expression of anger and increased BHR was robust for Americans. As predicted, however, this association was diametrically reversed for Japanese, among whom greater expression of anger predicted reduced BHR. These patterns were unique to the expressive facet of anger and remained after we controlled for age, gender, health status, health behaviors, social status, and reported experience of negative emotions. Implications for sociocultural modulation of bio-physiological responses are discussed.

Psychological resources as mediators of the association between social class and health: comparative findings from Japan and the USA.

BACKGROUND: Recently, researchers have proposed that psychological resources might be key concept in explaining the association between social class and health. However, empirical examinations of the extent to which psychological resources to social class in health are still few. PURPOSE: This study investigated mediating effects of selected psychological resources (sense of control, self-esteem, optimism, and neuroticism) on the association of social class [education and subjective social status (SSS)] with current health status (self-rated health and the number of chronic conditions). METHOD: This sample consisted of 1,805 Americans (818 males and 987 females) from the Midlife in the United States (MIDUS) survey, 2004-2006 and 1,027 Japanese (505 males and 522 females) from the Midlife in Japan (MIDJA) survey in Tokyo, Japan, 2008-2010. Information on social class, psychological resources, and health status was obtained using telephone interviews or written questionnaires. RESULTS: A mediation analysis was conducted separately for males and females in Japan and the USA. Neuroticism significantly mediated the association of education and SSS with self-rated health and chronic conditions among males and females in both countries, with one exception (not for chronic conditions among Japanese females). Sense of control significantly mediated the association of education and SSS with self-rated health among males and females in both countries. As hypothesized, self-esteem significantly mediated almost all of the associations of education and SSS with self-rated health and chronic conditions among men and women in the USA, but very few such associations in Japan. Optimism significantly mediated most associations of social class and health status in both countries, but only among females. CONCLUSIONS: Overall, the findings underscore important culture- and gender specificity in the ways in which psychosocial resources mediate the links between social class and health.

Defending honour, keeping face: Interpersonal affordances of anger and shame in Turkey and Japan.

In the present study, we tested the idea that emotions are afforded to the extent that they benefit central cultural concerns. We predicted that emotions that are beneficial for the Turkish concern for defending honour (both anger and shame) are afforded frequently in Turkey, whereas emotions that are beneficial for the Japanese concern for keeping face (shame but not anger) are afforded frequently in Japan. N=563 students from Turkey and Japan indicated how frequently people in their culture experience a range of interpersonal anger and shame situations, and how intense their emotions would be. As predicted, participants perceived emotional interactions to occur frequently to the extent that they elicited culturally beneficial emotions. Moreover, the affordance of culturally beneficial emotions differed in predictable ways not only between cultures but also within cultures between situations with close vs. distant others and male vs. female protagonists.

Negative emotions predict elevated interleukin-6 in the United States but not in Japan.

Previous studies conducted in Western cultures have shown that negative emotions predict higher levels of pro-inflammatory biomarkers, specifically interleukin-6 (IL-6). This link between negative emotions and IL-6 may be specific to Western cultures where negative emotions are perceived to be problematic and thus may not extend to Eastern cultures where negative emotions are seen as acceptable and normal. Using samples of 1044 American and 382 Japanese middle-aged and older adults, we investigated whether the relationship between negative emotions and IL-6 varies by cultural context. Negative emotions predicted higher IL-6 among American adults, whereas no association was evident among Japanese adults. Furthermore, the interaction between culture and negative emotions remained even after controlling for demographic variables, psychological factors (positive emotions, neuroticism, extraversion), health behaviors (smoking status, alcohol consumption), and health status (chronic conditions, BMI). These findings highlight the role of cultural context in shaping how negative emotions affect inflammatory physiology and underscore the importance of cultural ideas and practices relevant to negative emotions for understanding of the interplay between psychology, physiology, and health.

Aging and wisdom: culture matters.

People from different cultures vary in the ways they approach social conflicts, with Japanese being more motivated to maintain interpersonal harmony and avoid conflicts than Americans are. Such cultural differences have developmental consequences for reasoning about social conflict. In the study reported here, we interviewed random samples of Americans from the Midwest United States and Japanese from the larger Tokyo area about their reactions to stories of intergroup and interpersonal conflicts. Responses showed that wisdom (e.g., recognition of multiple perspectives, the limits of personal knowledge, and the importance of compromise) increased with increasing age among Americans, but older age was not associated with wiser responses among Japanese. Younger and middle-aged Japanese showed greater use of wise-reasoning strategies than younger and middle-aged Americans did. This cultural difference was weaker for older participants' reactions to interpersonal conflicts and was actually reversed for intergroup conflicts. This research has important implications for the study of aging, cultural psychology, and wisdom.

Self-referential processing accounts for cultural variation in self-enhancement versus criticism: An electrocortical investigation.

European Americans are self-enhancing, whereas East Asians are sometimes self-critical. However, the mechanisms underlying this cultural difference remain unclear. Here, we addressed this gap by testing 32 Taiwanese and 32 American young adults, who indicated whether their self-esteem would change in various episodes involving success or failure. We monitored their electroencephalogram (EEG) and assessed upper-alpha band power in response to the outcome information. An increase in upper-alpha power indicates internally directed attention; therefore, it is an index of self-referential processing when assessed during a judgment about the self. As predicted, Americans judged that their self-esteem (but not another's) would increase more after a success than it would decrease after a failure, thereby showing the previously observed self-enhancing pattern. Taiwanese tended to show the opposite pattern, self-criticism. Notably, Americans, but not Taiwanese, showed an increase in upper-alpha band power in response to the self's successes (vs. failures). This bias in the EEG index of self-referential processing predicted the cultural difference in self-enhancement (vs. criticism). The role of self-referential processing in self-enhancement is discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Population differences in proinflammatory biology: Japanese have healthier profiles than Americans.

The pleiotropic cytokine, interleukin-6 (IL-6), has emerged as a key factor in the biology of aging and the physiology of inflammation. Yet much of what we know about the normal functioning of IL-6 has been generated primarily from research on European populations and Americans of European descent. Our analyses compared IL-6 levels in 382 middle-aged and older Japanese to the values found in 1209 Caucasian- and African-Americans from the Midlife in the United States survey (MIDUS). Across the life span from 30 to 80 years of age, mean IL-6 levels were strikingly lower in Japanese individuals. Significantly lower levels of C-reactive protein (CRP) and fibrinogen (FBG) provided confirmatory evidence for a population difference in proinflammatory activity. Because IL-6 release has been associated with obesity, differences in body mass index (BMI) were taken into consideration. Japanese had the lowest, and African-Americans had the highest overall BMIs, but significant group differences in IL-6 persisted even after BMI was included as a covariate in the analyses. Additional support for distinct variation in IL-6 biology was generated when systemic levels of the soluble receptor for IL-6 (sIL-6r) were evaluated. Serum sIL-6r was higher in Japanese than Americans, but was most notably low in African-Americans. Our cytokine data concur with national differences in the prevalence of age-related illnesses linked to inflammatory physiology, including cardiovascular disease. The findings also highlight the importance of broadening the diversity of people included in population studies of health and aging, especially given the relative paucity of information for some Asian countries and on individuals of Asian heritage living in the US.

Oscillatory alpha power at rest reveals an independent self: A cross-cultural investigation.

In the current cultural psychology literature, it is commonly assumed that the personal self is cognitively more salient for those with an independent (vs. interdependent) self-construal (SC). So far, however, this assumption remains largely untested. Here, we drew on evidence that resting state alpha power (RSAP) reflects mental processes constituting the personal self, and tested whether RSAP is positively correlated with independent (vs. interdependent) SC. Study 1 tested European Americans and Taiwanese, whereas Study 2 tested European Americans and Japanese (total N = 164). A meta-analysis performed on the combined data confirmed a reliable association between independent (vs. interdependent) SC and RSAP. However, this association was only reliable when participants had their eyes closed. Even though European Americans were consistently more independent than East Asians, RSAP was no greater for European Americans than for East Asians. Our data helps explore a missing link in the theorizing of contemporary cultural psychology.

Japanese version of the 42-item psychological well-being scale (PWBS-42): a validation study.

BACKGROUND: The aim of this study was to examine the internal consistency, structural validity, and convergent/known-group validity of the Japanese version of the 42-item Psychological Well-Being Scale (PWBS-42). METHODS: The PWBS-42 includes six 7-item subscales designed to measure the following dimensions of eudaimonic psychological well-being: 1) autonomy, 2) environmental mastery, 3) personal growth, 4) positive relations with others, 5) purpose in life, and 6) self-acceptance. A questionnaire was administered to 2102 community residents in Tokyo aged 30 or over as a part of the Midlife in Japan (MIDJA) survey, in 2008. The internal consistency reliability was tested using Cronbach's α. Structural validity was examined using exploratory factor analysis (EFA). Convergent validity was evaluated by calculating correlations of the Japanese PWBS-42 subscales with life satisfaction, negative affect, negative adjectives, positive affect, positive adjectives, self-esteem, and perceived stress scales. RESULTS: Data from 1027 respondents (505 males and 522 females) were analyzed (valid response rate = 56.2%). Cronbach's α values ranged from 0.70 to 0.78 for five of the subscales, while that for purpose in life was lower (0.57). EFA yielded a five-factor structure: The first two factors consisted of negative and positive items mostly from the environmental mastery, purpose in life, and self-acceptance subscales. The third, fourth, and fifth factors consisted mostly of items from the positive relations with others, autonomy, and personal growth subscales, respectively. As hypothesized, the scores for life satisfaction, negative and positive affect/adjectives, self-esteem and perceived stress were significantly correlated with all subscales of the Japanese PWBS-42. CONCLUSION: The subscales of the Japanese version of the PWBS-42 showed accep. levels of reliability and support for convergent validity in the Japanese population. The factor structure was slightly different from the theoretical 6-factor model: items of three subscales (environmental mastery, purpose in life, and self-acceptance) loaded together on two factors. This finding may be interpreted in light of the interdependent self construal found in Japan in which these three components could be closely linked.

Age-Related Trends in the Prevalence of Type 2 Diabetes among Japanese and White and Black American Adults.

Aim: To compare the prevalence of poor glycemic control in probability samples of Japanese and American adults, and to determine the association with their somatic phenotypes. Material and Methods: Blood samples and anthropometric measures were obtained from 382 Japanese, 32-79 years of age, randomly selected to reflect the 23 wards of Tokyo. HA1c values were compared to 1215 Americans, 35-86 years of age, from a national study across the 48 continental states, along with an over-sampling of African-Americans from one city (www.midus.wisc.edu). Body Mass Index (BMI) and Waist-hip ratio (WHR) were also assessed. Results: Many Japanese now have high HA1c approaching Caucasian-American levels, although elevated HA1c (>6.5%, 48 mmol/mol) is not nearly as prevalent as among African-Americans. Significant age-related trends were evident in both countries, with poor glycemic control occurring at younger ages in males and rarely found until old age in Japanese women. Japanese had higher HA1c levels at BMIs of 23-25, in contrast to Americans with Type 2 diabetes who more typically had a BMI over 30. Central adiposity predicted HA1c levels better than BMI, a relationship also apparent at a smaller WHR in Japan. Conclusion: The prevalence of high HA1c in Tokyo almost rivals white Americans, but those statistics are dwarfed by the 37% of Afr-Amer adults identified with Type 2 diabetes. Elevated HA1c was more common in men, reflecting central adiposity, but poor glycemic control was also widespread among overweight Afr-Amer women. Type 2 diabetes was higher among older Japanese, when more women succumb. Overall, the findings highlight the societal and clinical challenges posed by demographic trends in both countries.

Feeling excited or taking a bath: Do distinct pathways underlie the positive affect-health link in the U.S. and Japan?

Feeling good is linked to better health in Western contexts. Recent studies show, however, that the affect-health link is not consistent across cultures. We suggest two reasons for such inconsistency. The first follows from research showing that North American (vs. East Asian) cultures tend to value high arousal positive (HAP) states, for example, excited, more than low arousal positive (LAP) states, for example, calm. The second is one we propose for the first time. Positive affective experience is manifest in internal feelings but also in affective practices, such as taking a bath (a highly valued affective experience in Japan) or a fitness workout (a highly valued affective experience in the United States). We hypothesized that the HAP feelings/practices-health link would be stronger in the United States versus Japan, and the LAP feelings/practices-health link would be stronger in Japan versus the United States. Using survey samples from the United States (N = 640) and Japan (N = 382), we examined how health outcomes are shaped by positive affective feelings and practices varying in arousal. In a first set of analyses, HAP feelings predicted better physical and biological health in the United States but not in Japan. No cultural differences were consistently found for the effect of LAP feelings on health. In addition, engaging in HAP practices predicted better physical and biological health in the United States whereas engaging in LAP practices predicted better physical health in Japan but not in the United States. These findings suggest that the pathways underlying the culture-health link are culturally variable. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

A cultural task analysis of implicit independence: comparing North America, Western Europe, and East Asia.

Informed by a new theoretical framework that assigns a key role to cultural tasks (culturally prescribed means to achieve cultural mandates such as independence and interdependence) in mediating the mutual influences between culture and psychological processes, the authors predicted and found that North Americans are more likely than Western Europeans (British and Germans) to (a) exhibit focused (vs. holistic) attention, (b) experience emotions associated with independence (vs. interdependence), (c) associate happiness with personal achievement (vs. communal harmony), and (d) show an inflated symbolic self. In no cases were the 2 Western European groups significantly different from one another. All Western groups showed (e) an equally strong dispositional bias in attribution. Across all of the implicit indicators of independence, Japanese were substantially less independent (or more interdependent) than the three Western groups. An explicit self-belief measure of independence and interdependence showed an anomalous pattern. These data were interpreted to suggest that the contemporary American ethos has a significant root in both Western cultural heritage and a history of voluntary settlement. Further analysis offered unique support for the cultural task analysis.

Neural signatures of child cognitive emotion regulation are bolstered by parental social regulation in two cultures.

Caregiver impact on the efficacy of cognitive emotion regulation (ER; i.e. reappraisal) during childhood is poorly understood, particularly across cultures. We tested the hypothesis that in children from Japan and the USA, a neurocognitive signature of effective reappraisal, the late positive potential (LPP), will be bolstered by cognitive scaffolding by parents, and explored whether the two cultures differed in whether mere physical proximity of parents provides similar benefit. Five-to-seven-year-olds (N = 116; nJapan = 58; nUSA = 58) completed a directed reappraisal task (EEG-recorded) in one of three contexts: (i) parent-scaffolding, (ii) parent-present and (iii) parent-absent. Across cultures, those in the parent-scaffolding group and parent-present group showed effective reappraisal via the LPP relative to those in the parent-absent group. Results suggest that scaffolding is an effective method through which parents in these two cultures buttress child ER, and even parental passive proximity appears to have a meaningful effect on child ER across cultures.

Behavioral Adjustment Moderates the Link Between Neuroticism and Biological Health Risk: A U.S.-Japan Comparison Study.

Neuroticism, a broad personality trait linked to negative emotions, is consistently linked to ill health when self-report is used to assess health. However, when health risk is assessed with biomarkers, the evidence is inconsistent. Here, we tested the hypothesis that the association between neuroticism and biological health risk is moderated by behavioral adjustment, a propensity to flexibly adjust behaviors to environmental contingencies. Using a U.S.-Japan cross-cultural survey, we found that neuroticism was linked to lower biological health risk for those who are high, but not low, in behavioral adjustment. Importantly, Japanese were higher in behavioral adjustment than European Americans, and as predicted by this cultural difference, neuroticism was linked to lower biological health risk for Japanese but not for European Americans. Finally, consistent with prior evidence, neuroticism was associated with worse self-reported health regardless of behavioral adjustment or culture. Discussion focused on the significance of identifying sociocultural correlates of biological health.