Effects of DHA Supplementation on Hippocampal Volume and Cognitive Function in Older Adults with Mild Cognitive Impairment: A 12-Month Randomized, Double-Blind, Placebo-Controlled Trial.

Docosahexaenoic acid (DHA) is important for brain function, and higher DHA intake is inversely correlated with relative risk of Alzheimer's disease. The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not been fully examined. Our study aimed to determine the effect of DHA supplementation on cognitive function and hippocampal atrophy in elderly subjects with MCI. This was a randomized, double-blind, placebo-controlled trial in Tianjin, China. 240 individuals with MCI aged 65 years and over were recruited and equalized randomly allocated to the DHA or the placebo group. Participants received 12-month DHA supplementation (2 g/day) or corn oil as placebo. Both global and specific subdomains of cognitive function and hippocampal volume were measured at baseline, 6 months, and 12 months. Both changes were analyzed by repeated-measure analysis of variance (ANOVA). This trial has been registered: ChiCTR-IOR-15006058. A total of 219 participants (DHA: 110, Placebo: 109) completed the trial. The change in mean serum DHA levels was greater in the intervention group (+3.85%) compared to the control group (+1.06%). Repeated-measures analyses of covariance showed that, over 12 months, there was a significant difference in the Full-Scale Intelligence Quotient (ηp2 = 0.084; p = 0.039), Information (ηp2 = 0.439; p = 0.000), and Digit Span (ηp2 = 0.375; p = 0.000) between DHA-treated versus the placebo group. In addition, there were significant differences in volumes of left hippocampus (ηp2 = 0.121, p = 0.016), right hippocampus (ηp2 = 0.757, p = 0.008), total hippocampus (ηp2 = 0.124, p = 0.023), and global cerebrum (ηp2 = 0.145, p = 0.032) between the two groups. These findings suggest that DHA supplementation (2 g/day) for 12 months in MCI subjects can significantly improve cognitive function and slow the progression of hippocampal atrophy. Larger, longer-term confirmatory studies are warranted.

Protective effects of allicin on streptozotocin-induced diabetic nephropathy in rats.

BACKGROUND: Studies in animal models have shown that allicin, a major biologically active component of garlic, can play a role in the prevention of tissue fibrosis in the liver, lung and heart, mainly related to the inhibition of fibroblast proliferation, fibrogenic cytokine secretion and extracellular matrix synthesis. This study aimed to investigate the protective effects of allicin on renal damage in streptozotocin (STZ)-induced diabetic rats. STZ-induced diabetic rats were administered allicin (15, 30 and 45 mg · kg-1 · day-1 ) via daily intra-gastric gavage for 12 weeks. The levels of fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (sCr), lipid and 24 h urine albumin excretion (UAE) were measured at the end of weeks 4, 8 and 12. The renal histopathology and the expression levels of collagen I, transforming growth factor ß1 (TGF-ß1) and phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) were measured using immunohistochemistry and/or western blotting. RESULTS: In 12 week STZ-induced diabetic rats, severe hyperglycemia and albuminuria were markedly developed. Treatment with allicin for 12 weeks ameliorated diabetes-induced morphological alterations of the kidney and decreased FBG, BUN, sCr, triglyceride (TG) and 24 h UAE in diabetic rats. The expression levels of collagen I, TGF-ß1 and p-ERK1/2 were significantly decreased by allicin treatment. CONCLUSION: These results suggested that allicin may play a protective role in diabetic nephropathy via the TGF-ß1/ERK pathway in diabetic rats. © 2016 Society of Chemical Industry.

Folic acid supplementation improves cognitive function by reducing the levels of peripheral inflammatory cytokines in elderly Chinese subjects with MCI.

This study aimed to evaluate whether folic acid supplementation would improve cognitive performance by reducing serum inflammatory cytokine concentrations. This RCT was performed in Tianjin, China. Participants with mild cognitive impairment (MCI) were randomly assigned to the folic acid (400 µg/day) or conventional treatment groups. Neuropsychological tests were administered, and folate, homocysteine, vitamin B12, IL-6, TNF-α, Aß-42, and Aß-40 were measured at baseline and at 6- and 12-month time points.152 participants (folic acid: 77, conventional: 75) completed the trial. Significant improvements in folate (ηp2 = 0.703, P = 0.011), homocysteine (ηp2 = 0.644, P = 0.009), Aß-42 (ηp2 = 0.687, P = 0.013), peripheral IL-6 (ηp2 = 0.477, P = 0.025), TNF-α (ηp2 = 0.709, P = 0.009) levels were observed in folic acid group compared with conventional group. Folic acid supplementation improved the Full Scale Intelligence Quotient (P = 0.028; effect size d = 0.153), Information (P = 0.031; d = 0.157) and Digit Span (P = 0.009; d = 0.172) scores at 12 months compared with conventional treatment. Based on these findings, daily oral administration of a 400-µg folic acid supplement to MCI subjects for 12 months can significantly improve cognitive performance and reduce peripheral inflammatory cytokine levels.

Folic Acid Supplementation Mitigates Alzheimer's Disease by Reducing Inflammation: A Randomized Controlled Trial.

Background/Aims. Low serum folate levels can alter inflammatory reactions. Both phenomena have been linked to Alzheimer's disease (AD), but the effect of folic acid on AD itself is unclear. We quantified folate supplementation's effect on inflammation and cognitive function in patients with AD over the course of 6 months. Methods. Patients newly diagnosed with AD (age > 60 years; n = 121; mild to severe; international criteria) and being treated with donepezil were randomly assigned into two groups with (intervention group) or without (control group) supplemental treatment with folic acid (1.25 mg/d) for 6 months. The Mini-Mental State Examination (MMSE) was administered to all patients at baseline and follow-up, and blood samples were taken before and after treatment. We quantified serum folate, amyloid beta (Aß), interleukin-6 (IL-6), tumor necrosis factor α (TNFα), plasma homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and the mRNA levels of presenilin (PS), IL-6, and TNFα in leukocytes. Data were analyzed using a repeated-measures mixed model. Results. The mean MMSE was slightly increased in the intervention group compared to that in the control group (P < 0.05). Posttreatment, plasma SAM and SAM/SAH levels were significantly higher (P < 0.05), while Aß 40, PS1-mRNA, and TNFα-mRNA levels were lower in the intervention group than in the control group (P < 0.05). The Aß 42/Aß 40 ratio was also higher in the intervention group (P < 0.05). Conclusions. Folic acid is beneficial in patients with AD. Inflammation may play an important role in the interaction between folic acid and AD. This trial is registered with clinical trial registration number ChiCTR-TRC-13003246.

Effects of 6-Month Folic Acid Supplementation on Cognitive Function and Blood Biomarkers in Mild Cognitive Impairment: A Randomized Controlled Trial in China.

BACKGROUND: This study is to examine the effects of folic acid supplementation on cognitive function in Chinese older adults with mild cognitive impairment who are unexposed to folic acid fortification and assess cognitive functioning in relation to folate, homocysteine, and vitamin B12 values at baseline. METHODS: This was a single-center, randomized, controlled trial in Tianjin, China; 180 individuals aged 65 years and older who had mild cognitive impairment were assigned randomly to one of two groups: (a) those treated with oral folic acid (400 µg/day) and (b) those treated via conventional treatment. Tests of cognitive performance and biomarkers were measured at baseline, 3 months, and 6 months. Analysis was by intention-to-treat. Changes in cognitive or clinical function were analyzed by repeated-measure analysis of variance or mixed-effects models. This trial has been registered with the trial number ChiCTR-TRC-13003227. RESULTS: Total of 159 participants (intervention group: 80; control group: 79) completed the trial. Repeated-measure analysis of variance showed significant improvements in serum folate (ηp (2) = 0.712, p = .009), homocysteine (ηp (2) = 0.119, p = .017), serum vitamin B12 (ηp (2) = 0.144, p = .022), and S-adenosylmethionine (ηp (2) = 0.117, p = .033) in the intervention group over the control group. Folic acid supplementation improved Full Scale IQ (p = .031; effect size d = 0.168), Digit Span (p = .009; d = 0.176), and Block Design (p = .036; effect size d = 0.146) scores at 6 months in comparison to the control. There were no significant findings for all other cognitive measures. CONCLUSION: There was a beneficial effect from relatively short-term folate supplementation on cognitive functioning in later life. Larger-scale, randomized, controlled trials of longer duration in selected age groups are needed.