Cigarette smoking and progression of kidney dysfunction: a longitudinal cohort study

INTRODUCTION

Cigarette smoking is one of the most important life-modifiable risk factors for CVD events. The effect on CKD progression caused by smoking remained uncertain, while the effect on CVD had been established.

METHOD

The study population included participants from the specific health check and specific health guidance, an annual health check-up for all inhabitants of Japan who were aged between 40 and 74 years. 149,260 subjects (male, 37.1%; female, 62.9%) were included in this analysis.

RESULTS

The relationship between smoking status along with new-onset proteinuria and eGFR deterioration more than 15 mL/min/1.73 m2 was examined. Median observation periods were 1427 days [738, 1813] in males and 1437 days [729, 1816] in females. In male participants, the strongest factor upon kidney dysfunction was new-onset proteinuria (1.41 [1.31 1.51], P < 0.001). The second strongest factor on kidney deterioration was smoking (1.24 [1.16 1.31], P < 0.001). In female participants, strongest factor upon kidney dysfunction was smoking (1.27 [1.16-1.39], P < 0.001). The second strongest factor on kidney deterioration was new-onset proteinuria (1.26 [1.17 1.36], P < 0.001). To reveal the relationship of effects from new-onset proteinuria and smoking on the kidney function, the participants were divided into four groups with and without new-onset proteinuria and smoking. The group with both proteinuria and smoking had significantly worst renal prognosis (P for trend < 0.001).

CONCLUSION

Large longitudinal observation study revealed smoking has an evil effect on the progression of CKD. This evil effect could be observed in CKD patients with proteinuria as well as in general population without new-onset proteinuria.

Higher-level competence: Results from the Integrated Longitudinal Studies on Aging in Japan (ILSA-J) on the shape of associations with impaired physical and cognitive functions

AIM

This study aimed to examine the relationships between levels of competence and impaired physical and cognitive functions in older adults.

METHODS

We used a data set of the Integrated Longitudinal Studies on Aging in Japan for 2017 including 5475 community-dwelling older adults. Levels of competence were assessed using the Japan Science and Technology Agency Index of Competence (JST-IC). Grip strength (low grip strength: <28 kg for men and <18 kg for women) and gait speed (slow gait speed: <1.0 m/s for both sexes) were evaluated as physical function measurements, and the Mini-Mental State Examination (cognitive decline: <24 on the Mini-Mental State Examination) was used to assess cognitive function.

RESULTS

The JST-IC had areas under the curve estimated from receiver operating characteristic analysis ranging from 0.65 to 0.73 for detecting low function as assessed by these tests. Restricted cubic spline curves showed that the shape of the association between the JST-IC and impaired function depended on sex and the test used. The comparison between perfect and imperfect JST-IC scores showed significant differences in the prevalence of low grip strength in both sexes, slow gait speed in women, and cognitive decline in men.

CONCLUSIONS

It may be insufficient to identify those with impaired physical or cognitive function using the JST-IC. The shape of the association with the JST-IC varies across their measurements. Our findings can help interpret JST-IC scores in the context of low physical and cognitive functions. Geriatr Gerontol Int 2024; 24: 352-358.

Factors contributing to subjective well-being and supporting successful aging among rural Japanese community-dwelling older adults: A cross-sectional and longitudinal study

AIM

We aimed to identify the factors contributing to subjective well-being in community-dwelling older adults in rural Japan. This study explored the relationship among physical and mental health, socioeconomic status, and activity levels with regard to the subjective well-being of older adults.

METHODS

In the Frail Elderly in the Sasayama-Tamba Area study, a cohort investigation of independent older adults in a rural Japanese community, 541 of 844 participants completed a 2-year follow-up survey. Subjective well-being was assessed as a binary based on three factors - "happiness," "satisfaction with life" and "meaning in life" - using a subset of the World Health Organization's Quality of Life questionnaire. The improvement group transitioned from not having subjective well-being during the baseline survey to having subjective well-being during the follow-up survey. Furthermore, we used multivariable log-Poisson regression models to calculate the prevalence ratios of subjective well-being.

RESULTS

The cross-sectional study showed that sleep satisfaction, health services access satisfaction and having a higher-level functional capacity were positively associated with having "happiness" and "satisfaction with life." Furthermore, being aged ≥ 80 years and having financial leeway were positively associated with having "meaning in life." The longitudinal study showed that having a higher-level functional capacity was positively associated with improving "happiness" and "satisfaction with life." Being female was positively associated with improving "happiness" and "meaning in life," and health services access satisfaction and alcohol drinking were positively associated with improving "satisfaction with life" and "meaning in life," respectively.

CONCLUSIONS

These findings offer promising avenues for enhancing the subjective well-being of older adults. Geriatr Gerontol Int 2024; 24: 311-319.

Do the physical activity questions in the Japanese version of the Cardiovascular Health Study criteria truly reflect a decline in physical activity?

Older participants identified as having decreased physical activity according to the Japanese version of the Cardiovascular Health Study criteria did not show a significant reduction in accelerometer-measured physical activity. Despite its widespread use in Japanese studies, the Japanese version of the Cardiovascular Health Study physical activity questionnaire may not effectively capture declines in physical activity.

Serum Creatinine-Cystatin C Based Screening of Sarcopenia in Community Dwelling Older Adults: A Cross-Sectional Analysis

OBJECTIVES

To compare the discriminative capabilities for the manifestation of sarcopenia or physical frailty between serum creatinine- and cystatin C-derived indices among community-dwelling older adults.

DESIGN

Cross-sectional study.

SETTING

Primary Care and Community.

PARTICIPANTS

We utilized a subset of data from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, which was initiated in 2015 to gather comprehensive information on various health-related parameters among community-dwelling older individuals (age ≥65 years).

MEASUREMENTS

Five serum creatinine-cystatin C based indices including the Sarcopenia Index, the serum creatinine/cystatin C ratio, the disparity between serum cystatin-C-based and creatinine-based estimated GFR, the total body muscle mass index (TBMM), and the prediction equation for skeletal muscle mass index (pSMI) were employed. Sarcopenia and physical frailty were identified based on the Asian Working Group for Sarcopenia criteria and the revised Japanese version of the Cardiovascular Health Study criteria, respectively. The receiver operating characteristic (ROC) and logistic regression analyses were performed to assess the discriminative abilities of these tools.

RESULTS

In the analysis of 954 participants, 52 (5.5%) were identified with sarcopenia and 35 (3.7%) with physical frailty. Regarding sarcopenia discrimination, TBMM and pSMI both exhibited area under the curve (AUC) values exceeding 0.8 for both men and women. Concerning the identification of physical frailty, AUC values ranged from 0.61 to 0.77 for males and 0.50 to 0.69 for females. In the multivariate logistic regression analyses, only TBMM and pSMI consistently displayed associations with sarcopenia, irrespective of sex (P<0.001, respectively). On the other hand, no consistent associations were observed between the indices and physical frailty.

CONCLUSIONS

This study provides a robust association of a serum creatinine- and cystatin C-derived indices, especially TBMM and pSMI, with sarcopenia among community-dwelling older adults. Conversely, the application of these indices for the screening of physical frailty has its constraints, necessitating further investigation.

Decline of instrumental activities of daily living is a risk factor for nutritional deterioration in older adults: a prospective cohort study

BACKGROUND

The association between functional capacity and the subsequent risk of nutritional deterioration is yet to be understood. The purpose of this study was to elucidate the relationship between functional capacity, comprising instrumental activities of daily living (IADL), intellectual activity, and social function, and future decline in nutritional status.

METHODS

The current study is a two-year prospective cohort study. A total of 468 community-dwelling older adults without nutritional risks were enrolled. We used the Mini Nutritional Assessment Screening Form. Functional capacity, including IADL, intellectual activity, and social function, was assessed using the Tokyo Metropolitan Institute of Gerontology Index of Competence at baseline. The nutritional status was reassessed at a 2-year follow-up. Risk ratios (RR) of functional capacity for the incidence of nutritional decline were estimated.

RESULTS

Low functional capacity was significantly associated with future deterioration of nutritional status (RR 1.12, 95% confidence interval [CI] 1.02-1.25). Of the subdomains of functional capacity, IADL decline (adjusted RR 2.21, 95% CI 1.18-4.13) was an independent risk factor for the incidence of nutritional risk. Intellectual and social activities were not significant.

CONCLUSION

Decline in functional capacity, especially IADL, is a risk factor for future deterioration in nutritional status. Further studies are required to elucidate the effect of interventions for IADL decline on maintaining nutritional status in older adults.

Association Between Timed Up-and-Go Test and Future Changes in the Frailty Status in a Longitudinal Study of Japanese Community-Dwelling Older Adults

Purpose

This study aimed to evaluate the relationship between timed up-and-go (TUG) test time and changes in frailty status in a longitudinal cohort study of rural Japanese older adults.

Patients and Methods

This prospective cohort study included 545 community-dwelling older adults. Initial and 2-year follow-up surveys were conducted. We compared the number of the Japanese version of the Cardiovascular Health Study components during the follow-up period and classified the participants into three groups: the favorable change, unchanged as prefrail, and unfavorable change groups. Associations between changes in frailty status and TUG time in the first survey were examined. The predictive ability of the TUG test was determined using the receiver operating characteristic (ROC) curve.

Results

The favorable change group comprised 315 individuals (57.8%), the unchanged as prefrail group 105 (19.2%), and the unfavorable change group 125 (22.9%). TUG time was associated with the favorable and unfavorable changes after adjustment for covariates (OR 0.79, 95% CI 0.68-0.92, P=0.001 and OR 1.27, 95% CI 1.09-1.49, P=0.002). The ROC curve of TUG time as a predictor of unfavorable changes showed an area under the curve of 0.59. A cut-off point of TUG was calculated as 6.3 s with 49.6% sensitivity and 66.0% specificity.

Conclusion

TUG time in the first survey was significantly associated with changes in frailty status 2 years later. However, its predictive value as a stand-alone test is limited and has the potential to predict future changes in the frailty status in older adults in combination with other tests.

Questionnaire survey of geriatricians and primary care physicians' approaches to treating older patients with multimorbidity

AIM

Geriatricians and primary care physicians in Japan are expected to provide care to older patients with multimorbidity.

METHODS

A questionnaire survey was carried out to understand the current approaches to older patients with multimorbidity. A total of 3300 participants, including 1650 geriatric specialists (G) and 1650 primary care specialists (PC) were enrolled. A 4-point Likert scale was used to score the following items: diseases that cause difficulty in treatment (diseases), patient backgrounds that cause difficulty in treatment (backgrounds), important clinical factors and important clinical strategies. Statistical comparisons were made between the groups. In the Likert scale, higher scores show a greater degree of difficulty.

RESULTS

We obtained responses from 439 and 397 specialists in the G and PC, respectively (response rates 26.6 and 24.1%). The overall scores for "diseases" and "backgrounds" were significantly higher in the G than those in the PC (P < 0.001 and P = 0.018). The top 10 items in the "backgrounds" and in the "important clinical strategies" were all matched between the groups. The overall score of the "important clinical factors" was not statistically different between the groups; however, "low nutrition," "bedridden activities of daily living," "living alone" and "frailty" were found only in the top 10 items of the G, and "financial problems" was found in those of the PC.

CONCLUSIONS

Geriatricians and primary care physicians have many similarities and differences in their approaches to multimorbidity management. Therefore, there is an urgent need to establish a system in which they can share a common understanding to manage older patients with multimorbidity. Geriatr Gerontol Int 2023; ••: ••-••.

Estrogen contributes to the sex difference in the occurrence of senescence-related T cells during the development of visceral adipose tissue inflammation

It remains unclear whether sex differences exist during the development of visceral adipose tissue (VAT) inflammation associated with obesity. The purpose of this study was to clarify sex differences in the occurrence of senescence-related T cells (CD44^high PD-1+ CD4+), which play a key role in the progression of VAT inflammation associated with high-fat diet (HFD)-induced obesity. Phase I: C57BL/6N mice were fed either a control diet (HFC) or HFD from 5 weeks. The area under the curve of the oGTT was maximal at 15 weeks in HFD-fed males and at 21 weeks in females. At 17 weeks, VAT weights were similar, but an increase in the number of macrophages in the VAT was observed only in HFD-fed males. In addition, the numbers of regulatory and senescence-related T cells were consistently higher in males than in females. Phase II and III: Six-week-old female mice were randomly divided into sham-operation and bilateral ovariectomy (OVX) groups and fed either HFC or HFD from 7 weeks. OVX mice were subjected to 17β-estradiol releasing or placebo pellet implantation and fed HFC. Body and VAT weights were higher in the OVX group than the Sham. The number of macrophages did not change in the OVX group with either diet. HFC-fed OVX mice exhibited high senescence-related T cells in the VAT, resembling HFC-fed male mice. This change was abolished by 17β-estradiol replacement. Thus, we demonstrated different accumulation patterns of VAT immune cells between the sexes, revealing a role for estrogen in the appearance of senescence-related T cells.

Association between oral frailty and cystatin C-related indices-A questionnaire (OFI-8) study in general internal medicine practice

BACKGROUND

Cystatin C-related indices such as the ratio of creatinine to cystatin C (Cr/CysC) and the ratio of estimated glomerular filtration rate by cystatin C (eGFRcys) to creatinine eGFRcre (eGFRcys/eGFRcre) levels have been shown to be associated with muscle mass and strength and can be markers of sarcopenia. Oral frailty is defined as an age-related gradual loss of oral functions, accompanied by a decline in cognitive and physical functions. It results in adverse health-related outcomes in older age, including mortality, physical frailty, functional disability, poor quality of life, and increased hospitalization and falls. Therefore, poor oral health among the elderly is an important health concern due to its association with the pathogenesis of systemic frailty, suggesting it to be a multidimensional geriatric syndrome. The Oral Frailty Index-8 (OFI-8) is a questionnaire that can be used for easy screening of oral frailty. This study aimed to investigate whether cystatin C- related indices are different between patients with low to moderate risk of oral frailty and those at high risk of oral frailty, using the OFI-8 in attending a general internal medicine outpatient clinic.

MATERIALS AND METHODS

This is a cross-sectional study that included 251 patients with a mean age of 77.7±6.6 years and a median age of 77 years (128 men: mean age, 77.1±7.3 years; median age, 77 years and 123 women: mean age, 78.4±5.7 years; median age, 78 years) attending general internal medicine outpatient clinics. OFI-8 scores were tabulated by gender to determine whether there were differences between patients at low to moderate risk of oral frailty (OFI-8 score ≤3 points) and those at high risk (OFI-8 score ≥4 points) in Cr/CysC, eGFRcys/eGFRcre levels, height, weight, grip strength, etc. were examined.

RESULTS

The OFI-8 score was higher in women than in men, suggesting that oral frailty is more common in women. Cr/CysC, eGFRcys/eGFRcre and grip strength were significantly lower in both men and women in the high-risk group for oral frailty (OFI-8 score ≥ 4). Height, hemoglobin level, red blood cell count, and serum albumin levels were significantly lower in men with an OFI-8 score ≥4. Receiver operating characteristic curve (ROC) analysis also showed that Cr/CysC and eGFRcys/eGFRcre were significantly associated with an OFI-8 score≥4 in both men and women.

CONCLUSION

Cr/CysC and eGFRcys/eGFRcre were significantly lower in the high-risk group for oral frailty on the OFI-8in both men and women. A relationship exists among cystatin C-related indices, which can effectively screen systemic frailty. Similarly, the OFI-8 score can be used to effectively screen oral frailty. Thus, a collaboration that incorporates both systemic and oral frailty from medical and dental perspectives is required.

Upregulation of neuropeptide Y in cardiac sympathetic nerves induces stress (Takotsubo) cardiomyopathy

Substantial emotional or physical stress may lead to an imbalance in the brain, resulting in stress cardiomyopathy (SC) and transient left ventricular (LV) apical ballooning. Even though these conditions are severe, their precise underlying mechanisms remain unclear. Appropriate animal models are needed to elucidate the precise mechanisms. In this study, we established a new animal model of epilepsy-induced SC. The SC model showed an increased expression of the acute phase reaction protein, c-Fos, in the paraventricular hypothalamic nucleus (PVN), which is the sympathetic nerve center of the brain. Furthermore, we observed a significant upregulation of neuropeptide Y (NPY) expression in the left stellate ganglion (SG) and cardiac sympathetic nerves. NPY showed neither positive nor negative inotropic and chronotropic effects. On the contrary, NPY could interrupt β-adrenergic signaling in cardiomyocytes when exposure to NPY precedes exposure to noradrenaline. Moreover, its elimination in the left SG via siRNA treatment tended to reduce the incidence of SC. Thus, our results indicated that upstream sympathetic activation induced significant upregulation of NPY in the left SG and cardiac sympathetic nerves, resulting in cardiac dysfunctions like SC.

[Association between physical activity and apathy among community-dwelling older adults]

AIM

To determine the association between physical activity and apathy in community-dwelling older adults.

METHODS

This was a cross-sectional study. Apathy was assessed using three sub-items from the Geriatric Depression Scale 15 (GDS-3A) on apathy syndrome. Physical activity was measured using a wrist-worn accelerometer. Exercise intensity was classified as sedentary behavior, light-intensity physical activity, or moderate-to-vigorous-intensity physical activity. A logistic regression analysis was used to examine the association between apathy and physical activity for each exercise intensity level.

RESULTS

Seven-hundred and eighty-four participants (age 72.7±5.9 years old) were included. Of those, 103 (13.1%) were in the apathy group. A multivariate analysis adjusted for demographic factors revealed that decreased total physical activity (odds ratio [OR] = 0.947, 95% confidence interval [CI] = 0.912-0.984, p = 0.005), light-intensity physical activity (OR = 0.941, 95% CI = 0.899-0.985, p = 0.009), and increased sedentary behavior (OR = 1.002, 95% CI = 1.001-1.003, p = 0.007) were associated with a greater OR of apathy, although moderate-to-vigorous-intensity physical activity was not significant (OR = 0.916, 95% CI = 1.826-1.017, p = 0.100). However, in the final model adjusted for depressive symptoms and functional factors, the association was not found to be significant, and a strong association was observed between depressive symptoms and apathy.

CONCLUSION

Physical activity in older adults with apathy symptoms was decreased in this study. However, the associations seemed to be strongly affected by depressive symptoms, and physical activity was not independently associated with apathy.

Relationships between cystatin C and creatinine‐based eGFR with low tongue pressure in Japanese rural community‐dwelling older adults

Background

Sarcopenia is prevalent in patients with chronic kidney disease (CKD), which is defined as a low estimated glomerular filtration rate (eGFR). It has been reported that oral hypofunction characterized by decreased tongue pressure is related to sarcopenia. Although there are several previous reports regarding the association of renal dysfunction with oral hypofunction characterized by low tongue pressure, the association between tongue pressure and renal function is not fully understood.

Methods

This cross‐sectional study included 68 men aged 79.0 ± 4.8 years and 145 women aged 77.3 ± 5.4 years from a rural area in Hyogo Prefecture, Japan. We examined the relationships between cystatin C‐based CKD (CKDcys), creatinine‐based CKD (CKDcre), ratio of cystatin C‐based GFR (eGFRcys) divided by creatinine‐based GFR (eGFRcre): eGFRcys/eGFRcre, and tongue pressure in community‐dwelling older adults.

Results

Tongue pressure was significantly lower in participants with CKDcys than in those without CKDcys in men and women. However, there were no significant differences in tongue pressure with or without CKDcre. Tongue pressure was significantly lower in participants with eGFRcys/eGFRcre <1.0, than in those with eGFRcys/eGFRcre ≧ 1.0 in men. According to the receiver operating characteristic analysis, the optimal cut‐off value of tongue pressure for the presence of CKDcys was 36.6kPa, area under the curve (AUC) 0.74 (specificity 54.8%, sensitivity 84.6%) in men and 31.8kPa, AUC 0.65 (specificity 67.3%, sensitivity 60.5%) in women.

Conclusions

CKDcys but not CKDcre is associated with low tongue pressure. In addition, a lower eGFRcys/eGFRcre ratio is a useful screening marker of low tongue pressure in community‐dwelling older adults.

The relationship between bone density and the oral function in older adults: a cross-sectional observational study

BACKGROUND

Falls among older adults with a low bone density can lead to a bedridden state. Declining bone density increases the risk of falls resulting fractures in older adults. A person's physical performance is known to be closely related to bone density, and a relationship between the physical performance and the oral function is also known to exist. However, there currently is a lack of evidence regarding the relationship between bone density and the oral function. We assessed the relationship between the bone density and the both the oral function and physical performance among older adults.

PATIENTS AND METHODS

754 older adults aged 65 years or older who independently lived in rural regions and who were not taking any medications for osteoporosis participated. We checked all participants for osteoporosis using an ultrasonic bone density measuring device. Regarding the oral function, we evaluated the following factors: remaining teeth, occlusal support, masticatory performance, occlusal force, and tongue pressure. We also evaluated body mass index (BMI) and skeletal muscle mass Index as clinical characteristics. The normal walking speed, knee extension force and one-leg standing test were evaluated as physical performance. For the statistical analyses, we used the Mann-Whitney U test, chi-square test, the Kruskal-Wallis, and a multiple regression analysis.

RESULTS

Eighty-one percent of the females and 58% of the males had osteoporosis or a decreased bone mass. The occlusal force, masticatory performance and the tongue pressure showed significant association with the bone density. The participants physical performance showed a significant association with their bone states except for walking speed. According to a multiple regression analysis, clinical characteristics (sex, age, BMI), one-leg standing and occlusal force showed independent associations with the bone density. It was suggested that the bone density tends to increase if the occlusal force is high and/or the one-leg standing test results are good.

CONCLUSIONS

The bone density in the older adults showed a significant relationship not only with clinical characteristics or physical performance, but also with occlusal force. It may also be effective to confirm a good oral function in order to maintain healthy living for older adults.

Estimation of Muscle Mass Using Creatinine/Cystatin C Ratio in Japanese Community-Dwelling Older People

OBJECTIVES

Sarcopenia is defined as a combination of low skeletal muscle mass index (SMI), weak muscle strength, and reduced physical function. Recently, many studies have reported that the creatinine/cystatin C ratio (Cr/CysC) is useful for evaluating muscle mass. We designed a cross-sectional study with separate model development and validation groups to develop a prediction equation to estimate bioimpedance analysis (BIA)-measured SMI with Cr/CysC.

DESIGN

The current study was a retrospective cross-sectional study.

SETTING AND PARTICIPANTS

The model development group included 908 subjects (288 men and 620 women) from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, and the validation group included 263 subjects (112 men and 151 women) from participants in the medical checkup program at the Anti-Aging Center in Ehime Prefecture.

MEASURES

Multivariate regression analysis indicated that age, hemoglobin (Hb), body weight (BW), and Cr/CysC were independently associated with SMI in both men and women. The SMI prediction equation was developed as follows: Men:4.17-0.012×Age+1.24×(Cr/CysC)-0.0513×Hb+0.0598×BW Women:3.55-0.00765×Age+0.852×(Cr/CysC)-0.0627×Hb+0.0614×BW RESULTS: The SMI prediction equation was applied to the validation group and strong correlations were observed between the BIA-measured and predicted SMI (pSMI) in men and women. According to the receiver operator characteristic (ROC) analysis, the areas under the curve were 0.93 (specificity 89.0%, sensitivity 87.2%) among men and 0.88 (specificity 83.6%, sensitivity 79.6%) among women for using pSMI to identify low SMI in the model development group. The pSMI also indicated high accuracy in ROC analysis for low SMI in the validation group. The Bland-Altman plot regression showed good agreement between BIA-measured and pSMI.

CONCLUSIONS AND IMPLICATIONS

Our new prediction equation to estimate SMI is easy to calculate in daily clinical practice and would be useful for diagnosing sarcopenia.

The effect of caloric restriction on the increase in senescence-associated T cells and metabolic disorders in aged mice

Aging is associated with functional decline in the immune system and increases the risk of chronic diseases owing to smoldering inflammation. In the present study, we demonstrated an age-related increase in the accumulation of Programmed Death-1 (PD-1)⁺ memory-phenotype T cells that are considered “senescence-associated T cells” in both the visceral adipose tissue and spleen. As caloric restriction is an established intervention scientifically proven to exert anti-aging effects and greatly affects physiological and pathophysiological alterations with advanced age, we evaluated the effect of caloric restriction on the increase in this T-cell subpopulation and glucose tolerance in aged mice. Long-term caloric restriction significantly decreased the number of PD-1⁺ memory-phenotype cluster of differentiation (CD) 4⁺ and CD8⁺ T cells in the spleen and visceral adipose tissue, decreased M1-type macrophage accumulation in visceral adipose tissue, and improved insulin resistance in aged mice. Furthermore, the immunological depletion of PD-1⁺ T cells reduced adipose inflammation and improved insulin resistance in aged mice. Taken together with our previous report, these results indicate that senescence-related T-cell subpopulations are involved in the development of chronic inflammation and insulin resistance in the context of chronological aging and obesity. Thus, long-term caloric restriction and specific deletion of senescence-related T cells are promising interventions to regulate age-related chronic diseases.

Associations Between Arterial Stiffness Indices and Chronic Kidney Disease Categories in Essential Hypertensive Patients

BACKGROUND

This study investigated the association between arterial stiffness indices and asymptomatic chronic kidney disease (CKD) risk categories in hypertensive patients.

METHODS

Arterial stiffness indices, including 24-hour brachial and aortic systolic blood pressure (SBP) and pulse wave velocity (PWV), were measured by an oscillometric Mobil-O-Graph device, brachial-ankle PWV (baPWV) by a volume-plethysmographic method, and renal resistive index (RI) by ultrasonography, in 184 essential hypertensive patients (66.0 ± 17.1 years, 47.3% male). CKD was categorized into 3 stages based on the Kidney Disease Improving Global Outcomes (KDIGO) criteria, using a combination of estimated glomerular filtration and albuminuria.

RESULTS

The 24-hour aortic PWV (aPWV), baPWV, and RI increased with worsening severity of CKD risk category (all P < 0.01 for trend). Multivariate logistic regression analysis found that a 1 SD increase of nighttime aortic SBP (odds ratio [OR] 1.52), PWV (OR 4.80), or RI (OR 1.75) was an independent predictor of high or very-high CKD stage (all P < 0.05). After adjustment for potential confounders, day-to-night change in brachial SBP as well as in aPWV differed among groups (P < 0.05, respectively). In a multivariate regression model, day-to-night changes in aortic SBP and PWV, and RI were independently associated with day-to-night brachial SBP change.

CONCLUSIONS

In hypertension, circadian hemodynamics in high CKD stage are characterized by higher nighttime values of aortic SBP and PWV and disturbed intrarenal hemodynamics. Further, the blunted nocturnal BP reduction in these patients might be mediated via disturbed intrarenal hemodynamics and circadian hemodynamic variation in aortic SBP and arterial stiffness.

Association between Physical Frailty Subdomains and Oral Frailty in Community-Dwelling Older Adults

This cross-sectional study aimed to demonstrate the association between physical frailty subdomains and oral frailty. This study involved community-dwelling older adults (aged ≥65 years). Physical frailty was assessed with the Japanese version of the Cardiovascular Health Study criteria. Oral frailty was defined as limitations in at least three of six domains. Logistic regression analysis was used to analyze the association between physical frailty risk and oral frailty. In addition, we examined the association between physical frailty subdomains (gait speed, grip strength, exhaustion, low physical activity, and weight loss) and oral frailty. A total of 380 participants were recruited for this study. Overall, 18% and 14% of the participants were at risk of physical frailty and had oral frailty, respectively. Physical frailty risk (odds ratio (OR) = 2.40, 95% confidence interval (CI): 1.22–4.75, p = 0.012) was associated with oral frailty in multivariate analysis. In secondary analysis, among physical frailty subdomains, gait speed (OR = 0.85, 95% CI: 0.73–0.97, p = 0.019) was associated with oral frailty. The present findings suggest that physical frailty is closely related to oral frailty. Among physical frailty subdomains, decreased gait speed in particular is an important indicator related to the development of oral frailty.

Does Oral Hypofunction Promote Social Withdrawal in the Older Adults? A Longitudinal Survey of Elderly Subjects in Rural Japan

It is often assumed that oral hypofunction is associated with social withdrawal in older adults because decreased motor function is related to decreased oral function. However, few studies have examined the relationship between social withdrawal in older adults and oral function. This longitudinal study aimed to clarify the relationship between changes in the level of social withdrawal and oral function in independent older adults. Participants were 427 older adults aged 65 years or older who took part in a self-administered questionnaire from 2016 to 2017 (baseline), and again two years later (follow-up). At baseline, 17 items related to oral function and confounding factors related to withdrawal, physical condition, physical function, and cognitive function were evaluated. A Cox proportional hazard model was used to examine the oral functions that negatively impact social withdrawal. The following factors were significantly associated with the worsening of social withdrawal: the number of remaining teeth, gingival condition, occlusal force, masticatory efficiency, and items related to swallowing and dry mouth. Older adults with cognitive issues who walk slowly and have a weak knee extension muscle were also significantly more likely to have oral frailty. Those who were found to have oral frailty at baseline were 1.8 times more likely to develop withdrawal compared to those with robust oral function. The results indicated that the worsening of withdrawal was associated with oral hypofunction at baseline. Since oral hypofunction was associated with the worsening of social withdrawal in older adults, it is important to maintain older adults' oral function.

Low back pain is closely associated with frailty but not with sarcopenia: Cross-sectional study of rural Japanese community-dwelling older adults

AIM

We speculated that low back pain, which is the most common ailment in older adults, is associated with frailty and/or sarcopenia and contributes to the progression of either condition. Our objective was to evaluate the relationship between low back pain, sarcopenia and frailty in rural Japanese community-dwelling older adults.

METHODS

We recruited 730 participants aged ≥65 years who underwent a comprehensive health examination between November 2016 and December 2018. The Oswestry Disability Index (ODI) was used to assess low back pain quantitatively, and scores were compared for the frail groups determined by the Japanese version of Cardiovascular Health Study, and the sarcopenia groups as determined by the Asian Working Group for Sarcopenia 2019.

RESULTS

Among 730 participants, the prevalence of low back pain was 57.8%. There were significant differences in the ODI scores between the robust, prefrail and frail groups (P < 0.001). In contrast, there were no significant differences in the ODI scores among the robust, low appendicular skeletal muscle and sarcopenia groups. Logistic regression analysis showed that the prevalence of low back pain and the ODI scores were significantly associated with frailty after adjustment for age, sex and body mass index (odds ratio 3.41, 95% confidence interval 1.39-8.39, P = 0.008, and odds ratio 1.06, 95% confidence interval 1.04-1.09, P < 0.001, respectively).

CONCLUSIONS

To the best of our knowledge, this study is the first to show the close association between low back pain and frailty, and suggests that not only the decline in physical function but also neuropsychiatric factors, including chronic pain, constitute a vicious cycle of frailty in community-dwelling older adults. Geriatr Gerontol Int 2021; 21: 54-59.

Physical frailty predicts the development of social frailty: a prospective cohort study

BACKGROUND

It has not been clarified whether physical frailty symptoms predict social. frailty. The purpose of this study was to elucidate the effect of physical frailty on social frailty, and to determine which domains of physical frailty predict the development of social frailty.

METHODS

We employed a two-year prospective cohort study. A total of 342 socially robust community-dwelling older adults were recruited. We used a modified social frailty screening index consisting of four social domains including financial difficulties, living alone, social activity, and contact with neighbors. Physical frailty status was also assessed at baseline. At the two-year follow-up, we assessed the development of social frailty. Social status was assessed using four social subdomains for the primary analysis. Social status was assessed using the two social subdomains of social activity and contact with neighbors, which would be affected by the physical frailty component, for the secondary analysis. The risk ratios (RR) of physical frailty for the development of social frailty were estimated.

RESULTS

Although physical frailty symptoms were not a significant risk factor for future development of social frailty as assessed by four social subdomains (adjusted RR 1.39, 95% CI 0.95-2.15), it became significant when development of social frailty was assessed by the two social subdomains (adjusted RR 1.78, 95% CI 1.10-2.88). An analysis using the physical frailty subdomain showed that slow gait speed (adjusted RR 3.41, 95% CI 1.10-10.53) and weakness (adjusted RR 1.06, 95% CI 1.01-1.12) were independent risk factors for development of social frailty as assessed by two social subdomains.

CONCLUSIONS

Physical frailty symptoms predict the development of social frailty. Among physical frailty subdomains, gait speed and muscle strength are critical independent risk factors for future decline in the social aspect. The prevention of physical frailty, especially by maintaining gait ability and muscle strength, may be effective for avoiding social frailty.

Prevalence of anti-cyclic citrullinated peptide antibodies in patients with spondyloarthritis: A retrospective study

OBJECTIVES

Anti-cyclic citrullinated peptide (CCP) antibodies are frequently detected in the sera of patients with rheumatoid arthritis (RA). However, recent studies have revealed a potentially high prevalence rate of these antibodies in patients with other rheumatic disorders, causing confusion while diagnosing RA. Therefore, this study aimed to evaluate the positive rate of anti-CCP antibodies in other chronic arthritis diseases focusing on patients with spondyloarthritis (SpA).

METHODS

A total of 109 patients who were diagnosed with SpA at Yukioka Hospital from 1993 to 2018 were included in this retrospective analysis, including patients with ankylosing spondylitis (AS); psoriatic arthritis (PsA); synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome (SAPHO); undifferentiated spondyloarthritis (uSpA); reactive arthritis (ReA); and inflammatory bowel disease-associated SpA (IBD).

RESULTS

Overall, 15.3% (16/109) of patients with SpA were positive for anti-CCP antibodies, including 2.3% (1/43) in AS, 23.1% (3/13) in SAPHO, 35.0% (7/20) in PsA, 14.8% (4/27) in uSpA, 0% (0/3) in ReA, and 33.3% (1/3) in IBD.

CONCLUSION

PsA patients have a significantly higher prevalence rate of positive anti-CCP antibodies among SpA patients, and the positive rates in SAPHO and uSpA were also high. These findings provide insight into the heterogeneity of SpA with relevance for RA differential diagnosis.

Palmitate induces cardiomyocyte death via inositol requiring enzyme-1 (IRE1)-mediated signaling independent of X-box binding protein 1 (XBP1)

Overloading of the saturated fatty acid (SFA) palmitate induces cardiomyocyte death. The purpose of this study is to elucidate signaling pathways contributing to palmitate-induced cardiomyocyte death. Palmitate-induced cardiomyocyte death was induced in Toll-like receptor 2/4 double-knockdown cardiomyocytes to a similar extent as wild-type cardiomyocytes, while cardiomyocyte death was canceled out by triacsin C, a long-chain acyl-CoA synthetase inhibitor. These results indicated that palmitate induced cytotoxicity after entry and conversion into palmitoyl-CoA. Palmitoyl-CoA is not only degraded by mitochondrial oxidation but also taken up as a component of membrane phospholipids. Palmitate overloading causes cardiomyocyte membrane fatty acid (FA) saturation, which is associated with the activation of endoplasmic reticulum (ER) unfolded protein response (UPR) signaling. We focused on the ER UPR signaling as a possible mechanism of cell death. Palmitate loading activates the UPR signal via membrane FA saturation, but not via unfolded protein overload in the ER since the chemical chaperone 4-phenylbutyrate failed to suppress palmitate-induced ER UPR. The mammalian UPR relies on three ER stress sensors named inositol requiring enzyme-1 (IRE1), PKR-like endoplasmic reticulum kinase (PERK), and activating transcription factor 6 (ATF6). Palmitate loading activated only IRE1 and PERK. Knockdown of PERK did not affect palmitate-induced cardiomyocyte death, while knockdown of IRE1 suppressed palmitate-induced cardiomyocyte death. However, knockdown of X-box binding protein 1 (XBP1), the downstream effector of IRE1, did not affect palmitate-induced cardiomyocyte death. These results were validated by pharmacological inhibitor experiments. In conclusion, we identified that palmitate-induced cardiomyocyte death was triggered by IRE1-mediated signaling independent of XBP1.

Basic survey for the prevention of intraoral residual medication in older adults: A pilot study

OBJECTIVE

This study aimed to assess the relationship between oral hygiene/stomatognathic function and residual intraoral medication in older adults and to identify the oral factors associated with residual oral medication.

METHODS

The study included 309 older adults (77 men, 232 women, mean age: 74.1 ± 7.4 years) who were prescribed medications at regular intervals. The following survey items were assessed: overall physical condition, intraoral condition and oral function. Participants prescribed oral medication were classified into groups with and without residual medication in the oral cavity. Statistical analysis was performed using univariate analysis for each of the factors contributing to the presence of residual medication.

RESULTS

Only 1.9% of all patients had residual medication, which suggests that older adults in this survey had a low risk of residual intraoral medication. However, greater attention should be given to residual intraoral medication in older adults receiving long-term care. Powdered-form oral medications were more likely to remain in the oral cavity. Older adults with residual medication had a tendency to have less occlusal support, poor tongue hygiene and poor tongue movement. Oral function, particularly functions that are closely related to swallowing, was significantly lower in the residual intraoral medication group when compared to those of the group without residual intraoral medication.

CONCLUSIONS

Reduced oral function and powered medication were associated with greater residual intraoral medication in this sample of older Japanese adults.

Is a History of Falling Related to Oral Function? A Cross-Sectional Survey of Elderly Subjects in Rural Japan

Background: Deteriorated physical function makes older adults prone to fall, and it is therefore known to prompt elders to require long-term care. In this regard, oral function can be related to the loss of motor function. This cross-sectional study assessed the oral factors that increase the risk of falling among older adults. Methods: We surveyed 672 self-reliant elderly individuals aged ≥65 years who were dwelling in a rural area. We assessed each subject’s risk of falling and any related anxiety. Oral-related conditions (number of teeth, occlusal support, masticatory performance, occlusal force, and tongue pressure) and physical motor functions (gait speed, knee extension force, and one-legged standing) were also assessed. Statistical analyses were performed using Mann-Whitney’s U-test, the χ² test, and a logistic regression model. Results: In all subjects, 23% had a history of falling, while 40% had anxiety over falling. Both factors were significantly higher among female subjects, who also had slower gait speeds, and greater lateral differences in occlusion. The subjects with histories of falling were older, had impaired physical motor function, and exhibited a decrease in occlusal force and left/right occlusal imbalances. We recognized similar trends for anxiety about falling. Conclusions: These results revealed that the risk of falling might be lessened by maintaining healthy teeth occlusion and promoting healthy oral function.

Circadian hemodynamic characteristics in hypertensive patients with primary aldosteronism

OBJECTIVE

The present study aimed to compare circadian hemodynamic characteristics in hypertensive patients with and without primary aldosteronism.

METHODS

Circadian hemodynamics, including 24-h brachial and central blood pressure (BP), SBP variability indices, central pulse wave velocity (PWV), augmentation index (AIx@75), cardiac index, and total vascular resistance (TVR), were evaluated using an oscillometric device, Mobil-O-Graph, in 60 patients with primary aldosteronism (63.4±13.3 years, 47% women) and 120 age-matched and sex-matched patients with essential hypertension.

RESULTS

Office SBP, PWV, AIx@75, and BP variability indices were similar between groups; however, 24-h brachial (124 ± 14 vs 130 ± 11 mmHg) as well as central (112 ± 12 vs 120 ± 10 mmHg) SBP was higher (both P < 0.01), and the difference between 24-h brachial and central SBP (11 ± 5 vs 9 ± 3 mmHg, P < 0.05), an index of pressure amplification, was smaller in primary aldosteronism than in essential hypertension. In both groups, cardiac index decreased from daytime to night-time (both P < 0.01), but this decrease was smaller in primary aldosteronism (P < 0.05). During daytime, TVR in primary aldosteronism was higher than that in essential hypertension (P < 0.05), and the significant increase of TVR from daytime to night-time was lost in primary aldosteronism. In a multivariate stepwise regression model, primary aldosteronism emerged as an independent predictor of 24-h central SBP as well as the difference between 24-h brachial and central SBP.

CONCLUSION

Our results demonstrated that circadian hemodynamics in primary aldosteronism patients are characterized by increased central SBP, smaller disparity between brachial and central SBP, and disturbed circadian hemodynamic variation.

Association Between Circadian Hemodynamic Characteristics and Target Organ Damage in Patients With Essential Hypertension

BACKGROUND

This study investigated the association between circadian hemodynamic characteristics and asymptomatic hypertensive organ damage.

METHODS

Circadian hemodynamics, including 24-hour brachial and aortic systolic blood pressure (SBP), pulse wave velocity (PWV), augmentation index (AIx@75), cardiac index, and total vascular resistance (TVR), were evaluated using an oscillometric device, Mobil-O-Graph, in 284 essential hypertensive patients (67.8 ± 16.0 years, 54% female). Hypertensive target organ damage (TOD), namely carotid wall thickening, left ventricular hypertrophy, and albuminuria, was assessed in all patients.

RESULTS

Office SBP and 24-hour brachial and aortic SBP all increased with increasing number of organs involved (all P < 0.01 for trend). After multivariate logistic regression analysis, 24-hour brachial SBP (odds ratio [OR] = 1.04 for 1 mm Hg increase, P < 0.001) as well as aortic SBP (OR = 1.03 for 1 mm Hg increase, P < 0.05) maintained significance. Percent decrease during nighttime in brachial SBP, PWV, and TVR, but not cardiac index, showed a significant graded relationship with the number of organs involved. In a multivariate stepwise regression model, the nighttime values of brachial SBP, PWV, and TVR emerged as independent predictors of the presence of TOD.

CONCLUSION

In essential hypertension, 24-hour aortic SBP could be a marker of subclinical TOD, and further, the blunted nocturnal BP reduction in TOD patients might be mediated by disturbed circadian hemodynamic variations in aortic SBP, vascular resistance, and arterial stiffness.

Relationship between oral environment and frailty among older adults dwelling in a rural Japanese community: a cross-sectional observational study

Background

Oral functions are known to decline with aging. However, there is limited evidence that supports the relationship between oral health and frailty. This study aimed to clarify the relationship between oral hygiene conditions, measured by remaining teeth and mucosa, and frailty among elderly people dwelling in a Japanese rural community.

Methods

We surveyed self-reliant elderly individuals aged ≥65 years who were dwelling in the Sasayama-Tamba area of Hyogo, Japan. Frailty was evaluated according to the total score of the Kihon Checklist (KCL). Based on the KCL score, elderly participants were divided into three groups: robust, pre-frail, and frail. The items measured to evaluate oral environment included the number of remaining teeth, denture usage condition, oral hygiene status, dry mouth condition, and salivary bacterial count. For statistical analysis, Fisher’s exact test, one-way analysis of variance, and multiple comparison technique were used.

Results

Of 308 elderly participants, 203 (65.9%), 85 (27.6%), and 20 (6.5%) belonged to the robust, pre-frail, and frail groups, respectively. The proportion of participants who were judged to have poor hygiene was significantly higher in the frail group than in the other two groups. The bacterial count was significantly smaller in the frail group than in the robust group, and the frail group had fewer number of remaining teeth than the other two groups, suggesting that the number of remaining teeth may be associated with bacterial count.

Conclusion

In elderly adults, physical frailty may affect the oral hygiene status and condition of the remaining teeth.

Decrease in membrane phospholipids unsaturation correlates with myocardial diastolic dysfunction

Increase in saturated fatty acid (SFA) content in membrane phospholipids dramatically affects membrane properties and cellular functioning. We sought to determine whether exogenous SFA from the diet directly affects the degree of membrane phospholipid unsaturation in adult hearts and if these changes correlate with contractile dysfunction. Although both SFA-rich high fat diets (HFDs) and monounsaturated FA (MUFA)-rich HFDs cause the same degree of activation of myocardial FA uptake, triglyceride turnover, and mitochondrial FA oxidation and accumulation of toxic lipid intermediates, the former induced more severe diastolic dysfunction than the latter, which was accompanied with a decrease in membrane phospholipid unsaturation, induction of unfolded protein response (UPR), and a decrease in the expression of Sirt1 and stearoyl-CoA desaturase-1 (SCD1), catalyzing the conversion of SFA to MUFA. When the SFA supply in the heart overwhelms the cellular capacity to use it for energy, excess exogenous SFA channels to membrane phospholipids, leading to UPR induction, and development of diastolic dysfunction.

Isotemporal substitution of sedentary time with physical activity and its associations with frailty status

OBJECTIVES

Recently, isotemporal substitution has been developed to substitute activity time for an equivalent amount of another activity. This study employed this method to demonstrate the effects of replacing sedentary behavior (SB) time with an equivalent amount of light-intensity physical activity (LPA) and moderate-to-vigorous intensity physical activity (MVPA) on the risk for different severities of frailty.

METHODS

A total of 886 older adults (average age 73.6 years, female 70%) participated in this cross-sectional study. Frailty status was assessed according to the cardiovascular health study criteria.

MAIN OUTCOME MEASURES

Wrist-worn accelerometers were used to measure SB, LPA, and MVPA. Isotemporal substitution models were applied to show the estimated effects of substituting 30 min of SB with an equal amount of time spent in LPA or MVPA on the risk for pre-frailty and frailty.

RESULTS

The physical activity level and SB were not associated with the incidence of pre-frailty. However, a 16% (OR: 0.84; 95% CI: 0.78-0.90) and 42% (OR: 0.58; 95% CI: 0.37-0.92) decrease in frailty risk was noted when SB was substituted with LPA and MVPA, respectively, in the crude model. In the adjusted model, the significant effect was sustained for LPA (OR: 0.86; 95% CI: 0.80-0.92) but not for MVPA (OR: 0.74; 95% CI: 0.47-1.17).

CONCLUSIONS

This study indicates that replacing 30 min of SB with an equivalent amount of LPA decreases the risk for frailty in older adults. Moreover, increasing LPA seems more feasible than increasing MVPA in older adults, with substantial benefit.

Relationship between sarcopenia and the serum creatinine/cystatin C ratio in Japanese rural community-dwelling older adults

Background:Sarcopenia, the age-related decline in skeletal muscle volume and function, is associated with negative clinical and socioeconomic outcomes in elderly people. Clinical biomarkers to diagnose sarcopenia that can be quantified in a reliable, and cost- effective manner, are needed. We investigated whether the creatinine (Cr) /cystatin C (CysC) ratio is correlated with muscle volume and physical function in Japanese community-dwelling elderly subjects. Methods: The present study included 213 men aged 73.2±6.2 years and 464 women aged 72.4±5.5 years from a rural area in the Hyogo prefecture of Japan. To evaluate whether the Cr/CysC ratio is correlated with sarcopenia criteria in elderly individuals with preserved kidney function, we excluded subjects with estimate glomerular filtration rate (eGFR) <45. Results:The prevalence of sarcopenia diagnosed according to the AWGS criteria was 2.8% in men and 3.4% in women. The Cr/CysC ratio correlated with skeletal mass index (r = 0.49, p <0.0001), skeletal muscle mass (r = 0.53, p <0.0001), grip power (r = 0.59, p <0.0001), knee extension muscle strength (r = 0.49, p <0.0001), normal gait speed (r = 0.18, p <0.0001), and maximal gait speed (r = 0.32, p <0.0001). A negative correlation between the Cr/CysC ratio and, body fat mass (r = -0.20, p <0.0001) and percentage of body fat mass (r = -0.39, p <0.0001) was observed. In a multiple regression analysis, Cr/CysC was also found to be significantly positively correlated with each component of the sarcopenia criteria. Conclusions:Even in elderly individuals with preserved kidney function, the Cr/CysC ratio was positively correlated with muscle volume and physical function and negatively correlated with body fat mass. Therefore, the Cr/CysC ratio might be a useful biomarker to predict sarcopenia. 

Abstract 207: Cytotoxic Effect of Palmitate is Caused by a Change in Membrane Fatty Acid Composition and ER Stress

Backgrounds: Saturated fat in diet is known to be detrimental to heart health, but its impact on the cardiac muscle remains unknown. We investigated the impact of saturated fatty acid overload on membrane fatty acid composition and survival in neonatal rat cardiomyocytes.

Methods and Results: (1) In neonatal rat cardiomyocytes, palmitate, a saturated fatty acid (16:0), induced cell death. (2) Palmitate-induced cell death was rescued by either co-administration of oleate (monounsaturated fatty acid; 18:1), EPA (polyunsaturated fatty acids; 20:5), or DHA (polyunsaturated fatty acids; 22:6). Among them, oleate was most effective. (3) Palmitate-overload did not alter the total amount of fatty acids in membrane phospholipid but changed the composition of fatty acids; it increased palmitate and decreased oleate. (4) Palmitate-induced cell death was associated with activation of ER stress sensors, referred as PERK, IRE1. Co-administration of oleate abolished ER stress. (5) Palmitate-induced cell death was significantly inhibited by APY29, an inhibitor of IRE1 phosphorylation pathway, but not by GSK260414 (PERK inhibitor) and by 4μ8c (IRE1-XBP1 inhibitor).

Conclusions: Palmitate-induced cell death in cardiomyocytes is associated with a change in membrane fatty acid composition and activation of ER stress. Lipotoxic effect of palmitate is attenuated by co-administration of oleate and an inhibitor of IRE1 phosphorylation pathway.

Obesity accelerates T cell senescence in murine visceral adipose tissue

Chronic inflammation in visceral adipose tissue (VAT) precipitates the development of cardiometabolic disorders. Although changes in T cell function associated with visceral obesity are thought to affect chronic VAT inflammation, the specific features of these changes remain elusive. Here, we have determined that a high-fat diet (HFD) caused a preferential increase and accumulation of CD44hiCD62LloCD4+ T cells that constitutively express PD-1 and CD153 in a B cell-dependent manner in VAT. These cells possessed characteristics of cellular senescence and showed a strong activation of Spp1 (encoding osteopontin [OPN]) in VAT. Upon T cell receptor stimulation, these T cells also produced large amounts of OPN in a PD-1-resistant manner in vitro. The features of CD153+PD-1+CD44hiCD4+ T cells were highly reminiscent of senescence-associated CD4+ T cells that normally increase with age. Adoptive transfer of CD153+PD-1+CD44hiCD4+ T cells from HFD-fed WT, but not Spp1-deficient, mice into the VAT of lean mice fed a normal diet recapitulated the essential features of VAT inflammation and insulin resistance. Our results demonstrate that a distinct CD153+PD-1+CD44hiCD4+ T cell population that accumulates in the VAT of HFD-fed obese mice causes VAT inflammation by producing large amounts of OPN. This finding suggests a link between visceral adiposity and immune aging.

Cardiac Sirt1 mediates the cardioprotective effect of caloric restriction by suppressing local complement system activation after ischemia-reperfusion

Caloric restriction (CR) confers cardioprotection against ischemia-reperfusion (I/R) injury. We previously found the essential roles of endothelial nitric oxide synthase in the development of CR-induced cardioprotection and Sirt1 activation during CR (Shinmura K, Tamaki K, Ito K, Yan X, Yamamoto T, Katsumata Y, Matsuhashi T, Sano M, Fukuda K, Suematsu M, Ishii I. Indispensable role of endothelial nitric oxide synthase in caloric restriction-induced cardioprotection against ischemia-reperfusion injury.Am J Physiol Heart Circ Physiol 308: H894-H903, 2015). However, the exact mechanism by which Sirt1 in cardiomyocytes mediates the cardioprotective effect of CR remains undetermined. We subjected cardiomyocyte-specific Sirt1 knockout (CM-Sirt1(-/-)) mice and the corresponding control mice to either 3-mo ad libitum feeding or CR (-40%). Isolated perfused hearts were subjected to 25-min global ischemia, followed by 60-min reperfusion. The recovery of left ventricle function after I/R was improved, and total lactate dehydrogenase release into the perfusate during reperfusion was attenuated in the control mice treated with CR, but a similar cardioprotective effect of CR was not observed in the CM-Sirt1(-/-)mice. The expression levels of cardiac complement component 3 (C3) at baseline and the accumulation of C3 and its fragments in the ischemia-reperfused myocardium were attenuated by CR in the control mice, but not in the CM-Sirt1(-/-)mice. Resveratrol treatment also attenuated the expression levels of C3 protein in cultured neonatal rat ventricular cardiomyocytes. Moreover, the degree of myocardial I/R injury in conventional C3 knockout (C3(-/-)) mice treated with CR was similar to that in the ad libitum-fed C3(-/-)mice, although the expression levels of Sirt1 were enhanced by CR. These results demonstrate that cardiac Sirt1 plays an essential role in CR-induced cardioprotection against I/R injury by suppressing cardiac C3 expression. This is the first report suggesting that cardiac Sirt1 regulates the local complement system during CR.

Neural crest-derived resident cardiac cells contribute to the restoration of adrenergic function of transplanted heart in rodent

AIMS

We investigated whether neural crest-derived cardiac resident cells contribute to the restoration of intrinsic adrenergic function following transplantation in mice. Transplanted heart shows partial restoration of cardiac adrenergic activity with time. Both the intrinsic cardiac adrenergic system and extrinsic sympathetic re-innervation contribute to neuronal remodelling in the transplanted heart. Little is known about the origin and function of the intrinsic system in the transplanted heart.

METHODS AND RESULTS

Heart from the protein 0-Cre/Floxed-Enhanced Green Fluorescent Protein double-transgenic mouse was transplanted onto the abdominal aorta of the non-obese diabetic/severe combined immunodeficient mouse to trace the fate of cardiac resident neural crest-derived cells. Sympathetic nerve fibres, which are predominantly localized to the epicardial surface of the heart, disappeared in the transplanted heart. Intramyocardial neural crest cells increased immediately, while neural crest-derived nucleated tyrosine hydroxylase (TH)-immunoreactive cells increased over 2 weeks following transplantation. The mRNA expression levels of TH, dopamine-β-hydroxylase and phenylethanolamine N-methyltransferase, and the tissue content of catecholamines in the transplanted hearts increased with time in association with an increase in the number of neural crest-derived nucleated TH-immunoreactive cells and tissue nerve growth factor levels. Iodine-123-metaiodobenzylguanidine scintigraphy showed that the uptake ability of transplanted heart for catecholamines also recovered with time. Finally, the chronotropic response to tyramine both in vivo and ex vivo reappeared 2 weeks after transplantation.

CONCLUSION

Neural crest-derived adrenergic cells increased following heart transplantation. The restoration of cardiac sympathetic activities in transplanted heart is tightly coupled with an increase in the number of neural crest-derived adrenergic cells.

Activation of pyruvate dehydrogenase by dichloroacetate has the potential to induce epigenetic remodeling in the heart

Dichloroacetate (DCA) promotes pyruvate entry into the Krebs cycle by inhibiting pyruvate dehydrogenase (PDH) kinase and thereby maintaining PDH in the active dephosphorylated state. DCA has recently gained attention as a potential metabolic-targeting therapy for heart failure but the molecular basis of the therapeutic effect of DCA in the heart remains a mystery. Once-daily oral administration of DCA alleviates pressure overload-induced left ventricular remodeling. We examined changes in the metabolic fate of pyruvate carbon (derived from glucose) entering the Krebs cycle by metabolic interventions of DCA. (13)C6-glucose pathway tracing analysis revealed that instead of being completely oxidized in the mitochondria for ATP production, DCA-mediated PDH dephosphorylation results in an increased acetyl-CoA pool both in control and pressure-overloaded hearts. DCA induces hyperacetylation of histone H3K9 and H4 in a dose-dependent manner in parallel to the dephosphorylation of PDH in cultured cardiomyocytes. DCA administration increases histone H3K9 acetylation in in vivo mouse heart. Interestingly, DCA-dependent histone acetylation was associated with an up-regulation of 2.3% of genes (545 out of 23,474 examined). Gene ontology analysis revealed that these genes are highly enriched in transcription-related categories. This evidence suggests that sustained activation of PDH by DCA results in an overproduction of acetyl-CoA, which exceeds oxidation in the Krebs cycle and results in histone acetylation. We propose that DCA-mediated PDH activation has the potential to induce epigenetic remodeling in the heart, which, at least in part, forms the molecular basis for the therapeutic effect of DCA in the heart.

Indispensable role of endothelial nitric oxide synthase in caloric restriction-induced cardioprotection against ischemia-reperfusion injury

Caloric restriction (CR) confers cardioprotection against ischemia-reperfusion injury (IRI). We previously found that treatment with N(G)-nitro-l-arginine methyl ester completely abrogates CR-induced cardioprotection and increases nuclear sirtuin 1 (Sirt1) expression. However, it remains unclear whether endothelial nitric oxide (NO) synthase (eNOS) plays a role in CR-induced cardioprotection and Sirt1 activation. We subjected eNOS-deficient (eNOS(-/-)) mice to either 3-mo ad libitum (AL) feeding or CR (-40%). Isolated perfused hearts were subjected to 25-min global ischemia followed by 60-min reperfusion. The degree of myocardial IRI in AL-fed eNOS(-/-) mice was more severe than that in AL-fed wild-type mice. Furthermore, CR did not exert cardioprotection in eNOS(-/-) mice. eNOS(-/-) mice exhibited elevated blood pressure and left ventricular hypertrophy compared with wild-type mice, although they underwent CR. Although nuclear Sir1 content was increased, the increases in cardiac Sirt1 activity with CR was absent in eNOS(-/-) mice. In eNOS(-/-) mice treated with hydralazine, blood pressure and left ventricular weight became comparable with CR-treated wild-type mice. However, CR-induced cardioprotection was not observed. Resveratrol enhanced cardiac Sirt1 activity but failed to mimic CR-induced cardioprotection in eNOS(-/-) mice. Finally, combination therapy with resveratrol and hydralazine attenuated myocardial IRI and reduced infarct size in eNOS(-/-) mice, and their effects were comparable with those observed in CR-treated wild-type mice. These results demonstrate the essential roles of eNOS in the development of CR-induced cardioprotection and Sirt1 activation during CR. The combination of a relatively low dose of resveratrol with an adequate vasodilator therapy might be useful for managing patients with endothelial dysfunction associated with impaired NO bioavailability.

Adventitial CXCL1/G-CSF expression in response to acute aortic dissection triggers local neutrophil recruitment and activation leading to aortic rupture

RATIONALE

In-hospital outcomes are generally acceptable in patients with type B dissection; however, some patients present with undesirable complications, such as aortic expansion and rupture. Excessive inflammation is an independent predictor of adverse clinical outcomes.

OBJECTIVE

We have investigated the underlying mechanisms of catastrophic complications after acute aortic dissection (AAD) in mice.

METHODS AND RESULTS

When angiotensin II was administered in lysyl oxidase inhibitor-preconditioned mice, AAD emerged within 24 hours. The dissection was initiated at the proximal site of the descending thoracic aorta and propagated distally into an abdominal site. Dissection of the aorta caused dilatation, and ≈70% of the mice died of aortic rupture. AAD triggered CXCL1 and granulocyte-colony stimulating factor expression in the tunica adventitia of the dissected aorta, leading to elevation of circulating CXCL1/granulocyte-colony stimulating factor levels. Bone marrow CXCL12 was reduced. These chemokine changes facilitated neutrophil egress from bone marrow and infiltration into the aortic adventitia. Interference of CXCL1 function using an anti-CXCR2 antibody reduced neutrophil accumulation and limited aortic rupture post AAD. The tunica adventitia of the expanded dissected aorta demonstrated high levels of interleukin-6 (IL-6) expression. Neutrophils were the major sources of IL-6, and CXCR2 neutralization significantly reduced local and systemic levels of IL-6. Furthermore, disruption of IL-6 effectively suppressed dilatation and rupture of the dissected aorta without any influence on the incidence of AAD and neutrophil mobilization.

CONCLUSIONS

Adventitial CXCL1/granulocyte-colony stimulating factor expression in response to AAD triggers local neutrophil recruitment and activation. This leads to adventitial inflammation via IL-6 and results in aortic expansion and rupture.

Lung Natural Killer Cells Play a Major Counter-Regulatory Role in Pulmonary Vascular Hyperpermeability After Myocardial Infarction

Rationale :

Natural killer (NK) cells are lymphocytes of the innate immune system that play specialized and niche-specific roles in distinct organs.

Objective :

We investigated the possible function of NK cells in the pathogenesis of congestive heart failure after myocardial infarction.

Methods and Results :

Depletion of NK cells from mice had little effect on cytokine expression (tumor necrosis factor-α, interleukin [IL]-6, and IL-1β), neutrophil and macrophage infiltration into infarcted myocardium, or left ventricular remodeling after myocardial infarction. However, these mice exhibited severe respiratory distress associated with protein-rich, high-permeability alveolar edema accompanied by neutrophil infiltration. In addition, there were 20-fold more NK cells in the mouse lungs than in heart, and these cells were accumulated around the vasculature. CD107a-positive and interferon-γ–positive cell populations were unchanged, whereas IL-10–positive populations increased. Adoptive transfer of NK cells from wild-type mice, but not from IL-10 knockout mice, into the NK cell–depleted mice rescued the respiratory phenotype. IL-1β–mediated dextran leakage from a lung endothelial cell monolayer was also blocked by coculture with NK cells from wild-type mice but not from IL-10 knockout mice.

Conclusions :

This study is the first to identify a critical role for lung NK cells in protecting lung from the development of cardiogenic pulmonary edema after myocardial infarction.

Endogenous prostaglandin D2 and its metabolites protect the heart against ischemia-reperfusion injury by activating Nrf2

We recently demonstrated that glucocorticoids markedly upregulate the expression of cyclooxygenase-2 in cardiomyocytes and protect hearts from ischemia-reperfusion (I/R) injury by activating lipocalin-type prostaglandin D (PGD) synthase (L-PGDS)-derived PGD(2) biosynthesis. We examined a downstream mechanism of cardioprotection elicited by PGD(2) biosynthesis. Acute PGD(2) treatment did not protect hearts against I/R injury. We then speculated that PGD(2) and its metabolite 15-deoxy-Δ12,14-PGJ(2) activate gene expression networks to mediate the glucocorticoid-mediated cardioprotection. Using an unbiased approach, we identified that glucocorticoids induce a number of well-known erythroid-derived 2-like 2 (Nrf2) target genes in the heart in an L-PGDS-dependent manner and that the cardioprotective effect of glucocorticoids against I/R injury was not seen in Nrf2-knockout hearts. We showed relatively low expression of PGD(2) receptors (ie, DP1 and DP2) in the heart but abundant expression of PGF(2α) receptor (FP), which binds PGF(2α) and PGD(2) with equal affinity. Glucocorticoids also failed to induce the expression of L-PGDS-dependent Nrf2 target genes in FP-knockout hearts. PGD(2) acted through its metabolite 15-deoxy-Δ12,14-PGJ(2) in the heart as evidenced by the glucocorticoid-mediated activation of peroxisome proliferator-activated receptor-γ. In turn, glucocorticoids failed to induce the expression of L-PGDS-dependent Nrf2 target genes in hearts pretreated with peroxisome proliferator-activated receptor-γ antagonist GW9662, and glucocorticoid-mediated cardioprotection against I/R injury was compromised in FP-knockout mice and GW9662-treated mice. In conclusion, PGD(2) protects heart against I/R injury by activating Nrf2 predominantly via FP receptor. In addition, we propose activation of peroxisome proliferator-activated receptor-γ by the dehydrated metabolite of PGD(2) (15-deoxy-Δ12,14-PGJ(2)) as another mechanism by which glucocorticoids induce cardioprotection.

Post-translational modification of mitochondrial proteins by caloric restriction: possible involvement in caloric restriction-induced cardioprotection

Increasing evidence demonstrates that members of the sirtuin family, most of which work as NAD(+)-dependent protein deacetylases, mediate the preferable effects of caloric restriction. Since mitochondria play a central role in cardiac reactive oxygen species production, targeted modification of mitochondrial proteins and subsequent improvement in mitochondrial function have the potential for controlling cardiovascular senescence and managing cardiovascular diseases such as ischemia/reperfusion. We showed that caloric restriction primes cardiac mitochondria for ischemic stress by deacetylating specific mitochondrial proteins of the electron transport chain. We speculate that deacetylation of specific mitochondrial proteins by sirtuin preserves mitochondrial function and attenuates myocardial oxidative damage during ischemia/reperfusion.