Associations among integrated psychoneuroimmunological factors and metabolic syndrome.

BACKGROUND: Metabolic syndrome (MetS) has been reported to cause considerable psychoneuroimmunology (PNI) disturbances such as, psychological distress, autonomic nervous imbalance, and impaired immune function. Associations among these psychoneuroimmunology (PNI) factors and their integrated effects with MetS and risk components of MetS necessitate further exploration. OBJECTIVE: This study investigated associations among psychoneuroimmunological factors, their integrated effects with MetS and risk components of MetS. METHODS: This was a cross-sectional study. Participants were recruited from two health management centers at a medical center in Northern Taiwan. Demographics and data on psychological distress (e.g., perceived stress and depression) were collected using self-reported questionnaires. Heart rate variability (HRV) and C-reactive protein values (CRP) were measured to evaluate participants' autonomic nervous function and immune reaction. The risk components of MetS (e.g., elevated blood pressure, impaired fasting glucose, dyslipidemia, and abdominal obesity) were identified according to the Taiwan-specific definition of MetS and were determined based on participants' health examination profiles. RESULTS: A total of 345 participants with complete data were included for data analysis. Compared with healthy controls, participants with MetS exhibited higher depression scores (11.2±8.5 vs. 8.7±7.0), higher CRP values (2.1±2.5 vs. 0.7±1.0), and lower HRV (total power: 758.7±774.9 vs. 1064.4±1075.0). However, perceived stress in participants with MetS did not significantly differ from that of their healthy counterparts (p>0.05). Univariate analyses indicated that associations among psychoneuroimmunological factors and MetS risk components were statistically heterogeneous: a) perceived stress and depression were significantly associated only with high blood glucose (p<0.05); b) CRP was significantly associated with all MetS risk components (p<0.05); and c) HRV was significantly associated with high triglycerides and high fasting blood glucose (p<0.05). Multivariate analysis indicated that the integrated effects of depression, CRP, and HRV were significantly associated with MetS (p<0.01) after controlling for age and education level. CONCLUSIONS: Higher depression scores, higher CRP values, and lower HRV are independently and additively associated with MetS and risk components of MetS. Accordingly, a multidisciplinary approach to alleviating psychological distress, immune dysfunction, and autonomic nervous imbalance is recommended for promoting well-being in people with subclinical metabolic abnormalities or MetS to minimize downstream health consequences.

Cinnamon users with prediabetes have a better fasting working memory: a cross-sectional function study.

Working memory (WM) is impaired in prediabetes. We hypothesized that culinary herbs and spices may decrease insulin resistance (IR) and improve WM in prediabetes. Healthy people aged ≥60 years with prediabetes (fasting blood glucose 100-125 mg/dL) (47 men and 46 women) whose food and culinary herb intakes were established with a food frequency questionnaire had body composition assessed and fasting glucose and insulin measured. Working memory and Mini-Mental State Examination (MMSE) were assessed on the same occasion. The contributions to associations between WM and diet, body fat, and IR were estimated by linear regression. Compared with nonusers, cinnamon users had significantly less frequent physical activity (2.9 vs. 4.4 times per week) and more often used fresh ginger (93.3% vs. 64.1%) and ginger in cooking (60.0% vs. 32.1%). Cinnamon users also had a better WM (2.9 vs. 2.5, P < .001). Cinnamon had a significant effect (users were 0.446 higher), but not ginger or curry usage, in predicting WM. For sociodemographic variables, only education (years) was significant in predicting WM (ß = 0.065). Other significant determinants of WM were total fat mass (kilograms) (ß = -0.024) and MMSE (ß = 0.075). After adjustment for age and sex, cinnamon use, education, and MMSE remained significant individual predictors. In the final model, in which all variables listed were adjusted simultaneously, cinnamon users still had a significantly higher WM than nonusers. Cinnamon usage is associated with a better WM, not accounted for by dietary quality or IR, in untreated prediabetes.

Turmeric improves post-prandial working memory in pre-diabetes independent of insulin.

BACKGROUND AND OBJECTIVES: Cognitive impairment develops with pre-diabetes and dementia is a complication of diabetes. Natural products like turmeric and cinnamon may ameliorate the underlying pathogenesis. METHODS: People ≥ 60 years (n=48) with newly-recognised untreated pre-diabetes were randomised to a double-blind metabolic study of placebo, turmeric (1 g), cinnamon (2 g) or both (1 g & 2 g respectively), ingested at a white bread (119 g) breakfast. Observations were made over 6 hours for pre- and post-working memory (WM), glycaemic and insulin responses and biomarkers of Alzheimer's disease (AD)(0, 2, 4 and 6 hours): amyloid precursor protein (APP), γ-secretase subunits presenilin-1 (PS1), presenilin-2 (PS2), and glycogen synthase kinase (GSK-3ß). Differences between natural product users and non-users were determined by Students t and chi square tests; and between pre-test and post-test WM by Wilcoxon signed rank tests. Interaction between turmeric and cinnamon was tested by 2-way ANOVA. Multivariable linear regression (MLR) took account of BMI, glycaemia, insulin and AD biomarkers in the WM responses to turmeric and cinnamon. RESULTS: No interaction between turmeric and cinnamon was detected. WM increased from 2.6 to 2.9 out of 3.0 (p=0.05) with turmeric, but was unchanged with cinnamon. WM improvement was inversely associated with insulin resistance (r=-0.418, p<0.01), but not with AD biomarkers. With MLR, the WM responses to turmeric were best predicted with an R2 of 34.5%; and with significant turmeric, BMI and insulin/glucose AUC beta-coefficients. CONCLUSIONS: Co-ingestion of turmeric with white bread increases working memory independent of body fatness, glycaemia, insulin, or AD biomarkers.