The moderating effect of religiosity on caregiving burden and depressive symptoms in caregivers of patients with dementia.

OBJECTIVES: This study explored whether religiosity/spirituality has a protective role against negative caregiving outcomes, in a large multicenter nationwide sample of caregivers of patients with dementia in South Korea. Additionally, this study was the first to examine whether religiosity/spirituality could affect caregiving outcomes according to the various religious affiliations of caregivers. METHODS: The study was conducted on a sample of 476 caregivers of patients with dementia participated in the Clinical Research Center for Dementia of South Korea (CREDOS). We examined the moderating effect of each of the three dimensions of religiosity/spirituality (organizational religious activity, ORA; non-organizational religious activity, NORA; intrinsic religiosity, IR) on the relationship between activities of daily living (ADL) of patients with dementia and caregiving burden and depressive symptoms of caregivers, using a series of hierarchical regression analyses. In addition, these analyses were conducted according to the religious affiliations of the caregivers. RESULTS: ORA, NORA, and IR of religiosity/spirituality alleviated the effect of ADL of patients on caregiving burden. ORA and IR moderated the relationship between ADL of patients and depressive symptoms of caregivers. These moderating effects of religiosity on caregiving outcomes were different according to various religious groups. CONCLUSION: We have identified religiosity/spirituality as a protective factor for caregivers of patients with dementia. The sub-dimensions of religiosity as moderators were different by religious affiliations of caregivers. Further studies are needed to investigate the specific religiosity-related factors which could positively impact the mental health of the caregivers of patients with dementia by religions.

Association between religiosity/spirituality and quality of life or depression among living-alone elderly in a South Korean city.

INTRODUCTION: This study investigated the effects of religiosity and spirituality on quality of life and depression among older people. METHODS: Two hundred and seventy-four solitary elderly people aged over 65 years living in Chuncheon city, South Korea were selected. Symptoms of depression were evaluated using the Short Geriatric Depression Scale-Korean version (SGDS-K) and quality of life was measured using Geriatric Quality of Life-Dementia (GQOL-D). We used the Duke Religion Index (DUREL) to assess religiosity and spirituality. RESULTS: There was a significant correlation between scales of depression (SGDS-K), quality of life (GQOL-D), and scale of religiosity/spirituality (DUREL) in older people. Depressed people had a lower score GQOL-D than non-depressed people. Among the depressed, those believing in a religion had a higher GQOL-D score than the non-religious. Multiple regression analysis revealed that religiosity and spirituality had significant effects on depression and quality of life among the elderly. Interestingly, religiosity and spirituality were not related to depression and quality of life amongst Buddhists, but were related amongst Protestants and Catholics. DISCUSSION: Religiosity and spirituality had significant effects on depression and on quality of life among the Korean elderly. However, there are different relationships between depression and religiosity, quality of life, and religiosity based on different religions. More research is needed to elucidate these findings.

Central or peripheral norepinephrine depletion enhances MK-801-induced plasma corticosterone level in mice.

To investigate the involvement of central or peripheral catecholaminergic systems in the MK-801-induced increase in plasma corticosterone and interleukin-6 levels, we pretreated mice either intracerebroventricularly (i.c.v.) or intraperitoneally (i.p.) with 6-hydroxydopamine (6-OHDA) which depletes catecholamines. Pretreatment of animals with 6-OHDA (50 microg i.c.v. or 100 mg/kg i.p.) significantly enhanced the MK-801 (1 microg i.c.v.)-induced increase in plasma corticosterone level. On the other hand, pretreatment of mice with 6-OHDA (50 microg i.c.v. or 100 mg/kg i.p.) did not affect the MK-801 (1 microg i.c.v.)-induced increase in plasma IL-6 level. These results suggest that central and peripheral catecholaminergic systems are involved in the suppressive regulation of MK-801-induced plasma corticosterone level.

Effect of Zen Meditation on serum nitric oxide activity and lipid peroxidation.

This study was designed to investigate the effect of Zen Meditation on serum nitric oxide activity (NO) and oxidative stress (lipid peroxidation). The experimental group included 20 subjects who had practiced the Zen Meditation program in Meditation Center located in Seoul, South Korea. The control group included 20 subjects who did not practice any formal stress management technique and were age and sex matched with experimental group. To provide an assessment of nitric oxide production, the serum level of nitrate/nitrite was determined using the Griess reagent. Malondialdehyde (MDA) concentration was measured as a convenient index of lipid peroxidation by thiobarbituric acid (TBA) method. Meditation group showed a significant higher level of serum nitrate+nitrite concentration and a significant reduced level of serum malondialdehyde (MDA) than control group. A comprehensive randomized controlled trial should be performed to prove the causal relationship between meditation and level of nitric oxide or oxidative stress in reducing cardiovascular risk factors.

Protection against beta-amyloid peptide-induced memory impairment with long-term administration of extract of Angelica gigas or decursinol in mice.

We investigated the effect of long-term oral administration of ethanolic extract of Angelica gigas Nakai (Umbelliferae) (EAG) or decursinol, a coumarin isolated from A. gigas, on beta-amyloid peptide 1-42 (Abeta(1-42))-induced memory impairment in mice. Mice were allowed free access to drinking water (control) or water containing different concentrations of EAG. After 4 weeks, Abeta(1-42) (410 pmol) was administered via intracerebroventricular injection. Pretreatment of mice with EAG (0.1%) for 4 weeks significantly blocked the Abeta(1-42)-induced impairment in passive avoidance performance. Next, mice were fed with chow mixed with various doses of decursinol for 4 weeks before intracerebroventricular injection of Abeta(1-42) (410 pmol). Pretreatment of mice with decursinol (0.001%, 0.002%, and 0.004%) for 4 weeks significantly attenuated the Abeta(1-42)-induced impairment in passive avoidance performance. Decursinol (0.004%) also significantly blunted the Abeta(1-42)-induced decrease in alternation behavior (spatial working memory) in the Y-maze test without change in general locomotor activity. These findings suggest that EAG or decursinol may have preventive effect against memory impairment related with Abeta of Alzheimer's disease.

The inhibitory effect of ginseng saponins on the stress-induced plasma interleukin-6 level in mice.

The effect of ginseng saponins on plasma interleukin-6 (IL-6) in non-stressed and immobilization-stressed mice were investigated. Ginseng total saponins, ginsenosides Rb2, Rg1 and Rd administered intraperitoneally attenuated the immobilization stress-induced increase in plasma IL-6 level. But, intracerebroventricular injection of each ginsenoside did not affect plasma IL-6 level induced by immobilization stress. Ginsenosides Rb2, Rd and Rg1 significantly decreased norepinephrine and/or epinephrine-induced increase of IL-6 level in macrophage cell line (RAW 264.7). Thus, it can be suggested that the inhibitory action of ginseng saponins against the immobilization stress-induced increase of plasma IL-6 level would be in periphery; at least in part, mediated by blocking norepinephrine- and/or epinephrine-induced increase of IL-6 level in macrophage rather than in the brain. Ginseng saponins might be proposed as a possible candidate in the research or therapeutic modulation of stress-related disorders.

Inhibition of intracerebroventricular injection stress-induced plasma corticosterone levels by intracerebroventricularly administered compound K, a ginseng saponin metabolite, in mice.

Effects of major intestinal metabolites of ginsenosides, including compound K (IH-901, 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol), compound Y (IH-902, 20-O-[alpha-L-arabinopyranosyl (1-->6)-beta-D-glucopyranosyl]-20(S)-protopanaxadiol), and ginsenoside Mc (IH-903, 20-O-[alpha-L-arabinofuranosyl (1-->6)-beta-D-glucopyranosyl]-20(S)-protopanaxadiol), on acute stress-induced plasma corticosterone levels were studied in mice. Intracerebroventricularly (i.c.v.) administered compound K (1 microg) attenuated the i.c.v. injection stress-induced increase in plasma corticosterone level, and this inhibitory effect was not affected by co-administered N(G)-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor. Compound K administered intraperitoneally affected neither the i.c.v. injection stress- nor the immobilization stress-induced increase in plasma corticosterone levels. Compound K and ginsenoside Mc did not affect plasma corticosterone levels induced by the two stress modalities used in this study.

Effects of ginseng saponin administered intraperitoneally on the hypothalamo-pituitary-adrenal axis in mice.

Intraperitoneal injection of ginseng total saponin (GTS; 5 and 20 mg/kg) raised plasma corticosterone levels in mice. However, interestingly, pretreatment of animals with the same doses of GTS (5 and 20 mg/kg) significantly attenuated the immobilization stress-induced increase in plasma corticosterone levels. Of the ginsenosides Rb(1), Rb(2), Rc, Rd, Re, Rf, Rg(1), 20(S)-Rg(3), and 20(R)-Rg(3) injected intraperitoneally at doses of 0.1-2 mg/kg, Rc (2 mg/kg) significantly inhibited the immobilization stress-induced increase in plasma corticosterone levels. GTS and Rc administered intraperitoneally did not affect the immobilization stress-induced elevation of plasma adrenocorticotropic hormone (ACTH) level. Pretreatment with GTS and Rc significantly attenuated the increase in plasma corticosterone levels induced by intraperitoneal injection of ACTH (30 microg/kg). These results suggest that GTS and Rc inhibit the immobilization stress-induced increase in plasma corticosterone levels by blocking ACTH action in the adrenal gland. Ginseng may be proposed to be useful for treatment of stress related disorders.