Moderate-to-vigorous Physical Activity and Sedentary Behavior Are Independently Associated With Renal Function: A Cross-sectional Study.

BACKGROUND: Little is known about whether insufficient moderate-to-vigorous physical activity (MVPA) and longer sedentary behavior (SB) are independently associated with estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD), whether they interact with known risk factors for CKD, and the effect of replacing sedentary time with an equivalent duration of physical activity on kidney function. METHODS: We examined the cross-sectional association of MVPA and SB with eGFR and CKD in 66,603 Japanese cohort study in 14 areas from 2004 to 2013. MVPA and SB were estimated using a self-reported questionnaire, and CKD was defined as eGFR <60 mL/min/1.73 m2. Multiple linear regression analyses, logistic regression analyses, and an isotemporal substitution model were applied. RESULTS: After adjusting for potential confounders, higher MVPA and longer SB were independently associated with higher eGFR (P for trend MVPA <0.0001) and lower eGFR (P for trend SB <0.0001), and a lower odds ratio (OR) of CKD (adjusted OR of MVPA ≥20 MET·h/day, 0.76; 95% confidence interval [CI], 0.68-0.85 compared to MVPA <5 MET·h/day) and a higher OR of CKD (adjusted OR of SB ≥16 h/day, 1.81; 95% CI, 1.52-2.15 compared to SB <7 h/day), respectively. The negative association between MVPA and CKD was stronger in men, and significant interactions between sex and MVPA were detected. Replacing 1 hour of SB with 1 hour of physical activity was associated with about 3 to 4% lower OR of CKD. CONCLUSION: These findings indicate that replacing SB with physical activity may benefit kidney function, especially in men, adding to the possible evidence on CKD prevention.

Successful treatment with granulocyte and monocyte adsorption apheresis for plaque-type skin lesions in patients with psoriatic arthritis.

INTRODUCTION: Granulocyte and monocyte adsorption apheresis (GMA) is usually performed weekly for refractory skin diseases, such as generalized pustular psoriasis and psoriatic arthritis (PsA). METHODS: Four patients with PsA who were refractory to previous treatments were enrolled. They received five or ten sessions of GMA. We assessed the clinical conditions of each patient and laboratory findings before and after GMA. RESULTS: GMA was effective in plaque-type skin eruptions in all four patients with PsA. It was also effective in joint symptoms in three patients with PsA with mild symptoms, but was ineffective in one patient with severe joint symptoms. CONCLUSION: GMA may be recommended to PsA patients with skin eruptions and mild joint symptoms.

Association Between the Appendicular Extracellular-to-Intracellular Water Ratio and All-Cause Mortality: A 10-Year Longitudinal Study.

The appendicular extracellular-to-intracellular water ratio (A-E/I) is a potential marker of skeletal muscle quality, reflecting the balance of water distribution between the extracellular and intracellular compartments of the appendicular limb regions. A-E/I has been increasingly used in recent studies; however, its association with adverse outcomes remains unclear. This study investigated the potential association between A-E/I and all-cause mortality. A prospective cohort study of 8 015 middle-aged and older adults (comprised of 4 755 women, aged 45-74 years) residing in a Japanese community was conducted. The baseline assessment was performed between 2010 and 2012, and the follow-up period lasted until July 2022. A-E/I and skeletal muscle mass were measured using segmental bioelectrical impedance spectroscopy. Handgrip strength (HGS) was measured using a Smedley-type dynamometer. Lifestyle, medical history, and physical activity were assessed by questionnaire and accelerometer. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for each quartile (Q) of A-E/I were estimated using the multivariable Cox regression model. During a 10.5-year median follow-up, the mortality rates were 8.9 and 3.6 per 1 000 person-years for men (292 deaths) and women (174 deaths), respectively. A-E/I quartiles were positively associated with all-cause mortality in both sexes (men: Q1, HR: 1.0 [95% CI: reference], Q4, HR: 1.8 [1.1-2.9], ptrend < .05; women, Q4, HR: 2.2 [1.3-3.8], ptrend < .01). This association remained significant after further adjustment for skeletal muscle mass and HGS (ptrend < .05). Our findings suggest that A-E/I serves as an early predictive marker for mortality in middle-aged and older Japanese adults.

Dose-response relationship between daily step count and prevalence of sarcopenia: A cross-sectional study.

OBJECTIVES: Daily step counts are an easy-to-understand indicator of physical activity; however, there is limited evidence regarding the optimal daily step count to prevent sarcopenia. This study examined the dose-response relationship between daily step count and the prevalence of sarcopenia and explored the optimal dose. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: The study included 7949 community-dwelling middle-aged and older adults (aged 45-74 years) from Japan. MEASUREMENTS: Skeletal muscle mass (SMM) was assessed using bioelectrical impedance spectroscopy, and muscle strength was quantified through handgrip strength (HGS) measurement. Participants who exhibited both low HGS (men: <28 kg, women: <18 kg) and low SMM (lowest quartile in each sex-specific category) were defined as having sarcopenia. Daily step counts were measured for 10 days using a waist-mounted accelerometer. To examine the association between daily step count and sarcopenia, a multivariate logistic regression analysis was performed, adjusting for potential confounding factors such as age, sex, body mass index, smoking status, alcohol consumption, protein intake, and medical history. The odds ratios (ORs) and confidence intervals (CIs) were calculated based on the daily step counts categorized into quartiles (Q1-Q4). Finally, a restricted cubic spline curve was fitted to further investigate the dose-response relationship between daily step count and sarcopenia. RESULTS: The prevalence of sarcopenia in the overall participants was 3.3 % (259/7949 participants), with a mean daily step count of 7292 ± 2966 steps. Expressed in quartiles, the mean daily step counts were 3873 ± 935 steps in Q1, 6025 ± 503 steps in Q2, 7942 ± 624 steps in Q3, and 11,328 ± 1912 steps in Q4. The prevalence of sarcopenia in each quartile of daily step count was 4.7 % (93/1987 participants) in Q1, 3.4 % (68/1987 participants) in Q2, 2.7 % (53/1988 participants) in Q3, and 2.3 % (45/1987 participants) in Q4. The ORs and 95 % CIs adjusted for covariates demonstrated a statistically significant inverse association between daily step count and sarcopenia prevalence (P for trend <0.01), as follows: Q1, reference; Q2, 0.79 (95 % CI: 0.55-1.11); Q3, 0.71 (95 % CI: 0.49-1.03); Q4, 0.61 (95 % CI: 0.41-0.90). The restricted cubic spline curve indicated that the ORs leveled off at approximately 8000 steps per day, and no statistically significant decrease in ORs was observed for daily step counts above this threshold. CONCLUSIONS: The study found a significant inverse association between daily step count and the prevalence of sarcopenia, with the association plateauing when the daily step count exceeded approximately 8000 steps. These findings suggest that 8000 steps per day may be the optimal dose to prevent sarcopenia. Further intervention and longitudinal studies are needed to validate the results.

Association of appendicular extracellular-to-intracellular water ratio with age, muscle strength, and physical activity in 8,018 community-dwelling middle-aged and older adults.

BACKGROUND: The appendicular extracellular-to-intracellular water ratio (Ap ECW/ICW) has recently gained attention as a non-invasive measurable marker of muscle quality. However, there is a lack of basic evidence regarding age-related changes, sex differences, contribution to muscle strength independent of skeletal muscle mass (SMM), and potential improvement through physical activity (PA) in Ap ECW/ICW. METHODS: This cross-sectional study enrolled 8,018 middle-aged and older Japanese individuals (aged 45-75 years). The Ap ECW/ICW and SMM were measured using segmental bioelectrical impedance spectroscopy. Muscle strength was evaluated by measuring the handgrip strength (HGS) with a dynamometer, and the PA level (PAL) was measured with an accelerometer. We performed a linear regression analysis of the associations of the Ap ECW/ICW with age, HGS, and PAL. RESULTS: The Ap ECW/ICW increased by 0.019 for men and 0.014 for women per 5-year increase in age (p < 0.001), and the age-related increase was greater in men than in women (p for interaction <0.001). The Ap ECW/ICW was more strongly associated with the HGS than with the SMM in both men and women (p < 0.001). PAL showed a significant inverse association with the Ap ECW/ICW in both men and women (p < 0.001). CONCLUSIONS: Ap ECW/ICW is higher with age, and it varies by sex. The Ap ECW/ICW may reflect muscle strength more than the SMM, suggesting that the Ap ECW/ICW may be improved by PA. The findings from this study may provide a framework for further Ap ECW/ICW research.

Coupling of in vitro Neocortical-Hippocampal Coculture Bursts Induces Different Spike Rhythms in Individual Networks.

Brain-state alternation is important for long-term memory formation. Each brain state can be identified with a specific process in memory formation, e.g., encoding during wakefulness or consolidation during sleeping. The hippocampal-neocortical dialogue was proposed as a hypothetical framework for systems consolidation, which features different cross-frequency couplings between the hippocampus and distributed neocortical regions in different brain states. Despite evidence supporting this hypothesis, little has been reported about how information is processed with shifts in brain states. To address this gap, we developed an in vitro neocortical-hippocampal coculture model to study how activity coupling can affect connections between coupled networks. Neocortical and hippocampal neurons were cultured in two different compartments connected by a micro-tunnel structure. The network activity of the coculture model was recorded by microelectrode arrays underlying the substrate. Rhythmic bursting was observed in the spontaneous activity and electrical evoked responses. Rhythmic bursting activity in one compartment could couple to that in the other via axons passing through the micro-tunnels. Two types of coupling patterns were observed: slow-burst coupling (neocortex at 0.1-0.5 Hz and hippocampus at 1 Hz) and fast burst coupling (neocortex at 20-40 Hz and hippocampus at 4-10 Hz). The network activity showed greater synchronicity in the slow-burst coupling, as indicated by changes in the burstiness index. Network synchronicity analysis suggests the presence of different information processing states under different burst activity coupling patterns. Our results suggest that the hippocampal-neocortical coculture model possesses multiple modes of burst activity coupling between the cortical and hippocampal parts. With the addition of external stimulation, the neocortical-hippocampal network model we developed can elucidate the influence of state shifts on information processing.

Variant Allele of ALDH2, rs671, Associates with Attenuated Post-Vaccination Response in Anti-SARS-CoV-2 Spike Protein IgG: A Prospective Study in the Japanese General Population.

Uncovering the predictors of vaccine immunogenicity is essential for infection control. We have reported that the most prevalent polymorphism of the aldehyde dehydrogenase 2 gene (ALDH2), rs671, may be associated with an attenuated immune system. To test the inverse relationship between rs671 and antibody production after COVID-19 vaccination, the levels of anti-SARS-CoV-2 Spike protein S1 subunit (S1) IgG were repeatedly measured for four months before and after vaccination with BNT162b2 or mRNA-1273, in 88 Japanese workers and students (including 45 females, aged 21-56 years, with an rs671 variant allele frequency of 0.3). The mixed model including fixed effects of the vaccine type, weeks post vaccination (categorical variable), sex, age, height, smoking status, ethanol intake, exercise habit, perceived stress, steroid use, allergic diseases, and dyslipidemia, indicated an inverse association between log-transformed anti-S1 IgG levels and the number of rs671 variant alleles (partial regression coefficient = -0.15, p = 0.002). Our study indicated for the first time that the variant allele of ALDH2, rs671, is associated with the attenuated immunogenicity of COVID-19 mRNA vaccines. Our finding may provide a basis for personalized disease prevention based on a genetic polymorphism that is prevalent among East Asians.

Effect of the interaction between physical activity and estimated macronutrient intake on HbA1c: population-based cross-sectional and longitudinal studies.

INTRODUCTION: Healthy diet and physical activity (PA) are essential for preventing type 2 diabetes, particularly, a combination of diet and PA. However, reports on interaction between PA and diet, especially from large epidemiological studies, are limited. We investigated the effect of interaction between PA and macronutrient intake on hemoglobin A1c (HbA1c) levels in the general population. RESEARCH DESIGN AND METHODS: We conducted a cross-sectional study of 55 469 men and women without diabetes who participated in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. A self-administered questionnaire ascertained PA and macronutrient intake (carbohydrate, fat, and protein). Multiple linear regression analyses were performed to adjust for confounding variables and examine the interactions. In addition, we conducted a longitudinal study during a 5-year period within a subcohort (n=6881) with accelerometer-assessed PA data. RESULTS: Overall, PA had a weak inverse association (ß=-0.00033, p=0.049) and carbohydrate intake had a strong positive association (ß=0.00393, p<0.001) with HbA1c. We observed a tendency of interactions between PA and carbohydrate or fat intake, but not protein intake, on HbA1c levels after adjusting for age, sex, study area, total energy intake, alcohol consumption, smoking, and medication for hypertension or hypercholesterolemia (Pinteraction=0.054, 0.006, and 0.156, respectively). The inverse associations between PA and HbA1c level were more evident in participants with high-carbohydrate (or low-fat) intake than in participants with low-carbohydrate (or high-fat) intake. Although further adjustment for body mass index slightly attenuated the above interactions (Pinteraction=0.098 for carbohydrate and 0.068 for fat), the associations between PA and HbA1c level in stratified analyses remained unchanged. Similar associations and interactions were reproduced in the longitudinal study. CONCLUSIONS: The present results suggest that the effect of PA on HbA1c levels is modified by intake of macronutrient composition.

Sex- and age-specific all-cause mortality in insomnia with hypnotics: Findings from Japan multi-institutional Collaborative Cohort Study.

OBJECTIVE: Findings on the increased mortality risk in individuals with insomnia are inconsistent across studies. Rather than improving insomnia by sleep control, hypnotic use may be one factor in the increased risk of death; however, the effects of hypnotics on mortality remains unclear. This study aimed to examine the association between all-cause mortality and hypnotic use in a large sample, while adjusting for the effects of comorbidities. METHODS: Overall, 92,527 individuals aged 35-69 years were followed up for mortality in the Japan Multi-Institutional Collaborative Cohort Study. Regular use of hypnotics was assessed using a self-administered questionnaire. Since cancer history carries a substantial risk of death and is associated with the treatment of insomnia with hypnotics, participants with a cancer history were excluded. The hazard ratio (HR) and 95% confidence interval (CI) for all-cause mortality related to hypnotic use were estimated using a Cox proportional hazard model with adjustments for covariates including sleeping hours and comorbidities (body mass index, ischemic heart disease, stroke, and diabetes). RESULTS: During the follow-up (mean, 8.4 ± 2.5 years), 1,492 mortalities were recorded, and the prevalence of taking hypnotics was 4.2%. Hypnotic use was associated with significantly greater risk of all-cause mortality, even after adjustment for the covariates (HR, 1.32; 95% CI, 1.07-1.63). The association between hypnotic use and all-cause mortality was robust in males (HR, 1.51; 95% CI, 1.15-1.96), and participants aged <60 years (HR, 1.75; 95% CI, 1.21-2.54). CONCLUSIONS: Our study revealed sex-age specific associations between hypnotic use and all-cause mortality.

Association of perceived stress and coping strategies with the renal function in middle-aged and older Japanese men and women.

Elucidating the risk factors for chronic kidney disease is important for preventing end-stage renal disease and reducing mortality. However, little is known about the roles of psychosocial stress and stress coping behaviors in deterioration of the renal function, as measured by the estimated glomerular filtration rate (eGFR). This cross-sectional study of middle-aged and older Japanese men (n = 31,703) and women (n = 38,939) investigated whether perceived stress and coping strategies (emotional expression, emotional support seeking, positive reappraisal, problem solving, and disengagement) were related to the eGFR, with mutual interactions. In multiple linear regression analyses adjusted for age, area, lifestyle factors, and psychosocial variables, we found a significant inverse association between perceived stress and the eGFR in men (Ptrend = 0.02), but not women. This male-specific inverse association was slightly attenuated after adjustment for the history of hypertension and diabetes and was more evident in lower levels of emotional expression (Pinteraction = 0.003). Unexpectedly, problem solving in men (Ptrend < 0.001) and positive reappraisal in women (Ptrend = 0.002) also showed an inverse association with the eGFR. Perceived stress may affect the eGFR, partly through the development of hypertension and diabetes. The unexpected findings regarding coping strategies require the clarification of the underlying mechanisms, including the hormonal and immunological aspects.

Na+-dependent inactivation of vascular Na+/Ca2+ exchanger responsible for reduced peripheral blood flow in neuropathic pain model.

Reduced skin blood flow has been reported in neuropathic pain patients as well as various peripheral neuropathic pain model animals. We have previously shown that vasodilators, which improves reduced skin blood flow, correlatively alleviate neuropathic pain in chronic constriction injury (CCI) mice, a model of neuropathic pain from peripheral nerve injury. Here, we sought to elucidate the mechanism underlying the reduced skin blood flow in CCI rats. The skin blood flow of the ipsilateral plantar arteries was significantly reduced compared to that of the contralateral ones 4 weeks after loose ligation of the sciatic nerve. The contraction induced by noradrenaline, serotonin, and U46619, a thromboxane receptor agonist, in the isolated ipsilateral plantar arteries was significantly enhanced compared to that in the contralateral ones. KB-R7943, a Na+/Ca2+ exchanger (NCX) inhibitor, shifted the concentration-response curves of noradrenaline to the left in the contralateral arteries but had no effect on the ipsilateral side. There was no significant difference in concentration-response curves of noradrenaline between the ipsilateral and contralateral arteries in the presence of KB-R7943. Amiloride, a non-specific inhibitor of Na+ channels and transporters, comparably shifted concentration-response curves of noradrenaline to the left in both the contralateral and ipsilateral arteries. One hundred nM of noradrenaline induced intracellular Ca2+ elevation in the ipsilateral arteries, which was significantly larger than that induced by 300-nM noradrenaline in the contralateral arteries. These results suggest that reduced peripheral blood flow after nerve injury is due to Na+-dependent inactivation of NCX in the ipsilateral plantar arteries.

Association between habitual coffee consumption and skeletal muscle mass in middle-aged and older Japanese people.

AIMS: Coffee consumption has been suggested, in animal studies, to inhibit the progression of sarcopenia, possibly through its anti-inflammatory effects; however, few studies have been carried out in humans. We aimed to examine whether coffee consumption was related to indicators of sarcopenia in a Japanese population, and whether the association was mediated by reduced inflammation. METHODS: This study was a cross-sectional design. Participants were community residents (n = 6369) aged 45-74 years. We measured skeletal muscle mass index (SMI; kg/m2 ) by a bioelectrical impedance method, and grip strength with a Smedley-type dynamometer. Habitual coffee consumption was assessed by a self-administered questionnaire. Serum high-sensitivity C-reactive protein was measured as an inflammatory marker. The association between habitual coffee consumption and SMI or grip strength was analyzed with a linear regression model adjusted for covariates. RESULTS: A significant positive association was found between coffee consumption and SMI (men: ß = 0.023; Ptrend  = 0.004, women: ß = 0.011; Ptrend  = 0.012). Further adjustment for high-sensitivity C-reactive protein did not materially alter the results (men: ß = 0.023; Ptrend  = 0.005, women: ß = 0.009; Ptrend  = 0.024). The relationship between coffee consumption and grip strength did not reach statistical significance; however, a positive trend was observed (men: ß = 0.208; Ptrend  = 0.085, women: ß = 0.092; Ptrend  = 0.167). CONCLUSIONS: We found that coffee consumption was positively associated with SMI independently of inflammation in middle-aged and older Japanese people. Reduced inflammation by coffee does not seem to be an important mediator, and further investigations are required to explore the mechanisms of this association. Geriatr Gerontol Int 2021; 21: 950-958.

Erratum: Publisher Correction: Simulated microgravity attenuates myogenic differentiation via epigenetic regulations.

[This corrects the article DOI: 10.1038/s41526-018-0045-0.].

Simulated microgravity attenuates myogenic differentiation via epigenetic regulations.

The molecular mechanisms involved in myogenic differentiation are relatively well-known. Myogenic differentiation is regulated by the sequential activation of the basic helix-loop-helix myogenic regulatory transcription factors (MRFs), and biomechanical signals play an important role in the regulation of myogenesis. In this study, we sought to determine whether simulated microgravity culture using Gravite® may affect myoblast differentiation and expression of MRF genes. Although rat myoblasts, L6 cells were differentiated to myotubes in an incubation period-dependent manner, myogenesis of L6 cells was significantly attenuated under simulated microgravity (10-3G) conditions. Real-time Reverse transcription polymerase chain reaction (RT-PCR) showed that expressions of Myog, Myf6, Mef2c, Des, and Ckm under 1 G conditions increase in an incubation period-dependent manner, and that Myod1 expression was specifically observed to increase transiently in the early phase. However, expressions of Myod1 and Myog were significantly inhibited under simulated microgravity conditions. To clarify the molecular mechanisms, L6 cells were treated with 5-AzaC, and further incubated with differentiation medium under 1 G or 10-3 G conditions. The results showed differences in expression levels of Myod1, Myog, and, as well as those of myotube thickness between 1 G and 10-3 G conditions, completely disappeared in this experimental condition. Modified HpaII tiny fragment enrichment by ligation-mediated PCR (HELP)-assay showed that kinetic changes of DNA methylation status were attenuated in simulated microgravity conditions. These results indicate that microgravity regulates myogenesis and Myod1 expression by controlling DNA methylation.