Prescription n-3 fatty acids, but not eicosapentaenoic acid alone, improve reference memory-related learning ability by increasing brain-derived neurotrophic factor levels in SHR.Cg-Lepr(cp)/NDmcr rats, a metabolic syndrome model

Lipase Treatment of Dietary Krill Oil, but Not Fish Oil, Enables Enrichment of Brain Eicosapentaenoic Acid and Docosahexaenoic Acid

SCOPE

Currently available omega-3 fatty acid supplements do not enrich the docosahexaenoic acid (DHA) of the adult brain because they are absorbed as triacylglycerol, whereas the transporter at the blood brain barrier requires lysophosphatidylcholine (LPC)-DHA. The hypothesis that treatment of krill oil (KO), which contains DHA/eicosapentaenoic acid (EPA) at the SN2 position of phosphatidylcholine, with SN1-specific lipase will generate LPC-DHA/EPA and which can be absorbed intact and transported into the brain, is tested.

METHODS

KO and fish oil (FO) are treated with Mucor meihei lipase, incorporated into AIN 93G diet, and fed to 2-month-old mice for 30 days. Fatty acid composition is analyzed by gas chromatography/mass spectroscopy. Brain derived neurotrophic factor (BDNF) is measured by ELISA.

RESULTS

Lipase-treated (LT) KO increases brain DHA and EPA, respectively, 5-and 70-fold better than untreated (UT) KO. FO, whether lipase-treated or not, has no effect on brain DHA/EPA. LTKO is also more efficient in enriching liver DHA/EPA, but less efficient than UTKO and FO in enriching adipose tissue and heart. Brain BDNF is significantly increased by LTKO, but only marginally by other preparations.

CONCLUSIONS

Pretreatment of dietary KO with lipase enables it to efficiently increase brain DHA/EPA because of the generation of LPC-DHA/EPA.

N-3 polyunsaturated fatty acids and clozapine abrogates poly I: C-induced immune alterations in primary hippocampal neurons

The viral mimetic polyinosinic:polycytidylic acid (poly I:C) is an important tool to study the consequences of viral infection to the development of neuropsychiatric disorders. Here, based on the premise of omega-3 polyunsaturated fatty acids (n3 PUFAs) as supplemental treatment to antipsychotics in schizophrenia, we investigated the involvement of NFkB pathway in the effects of n3 PUFAs or of the atypical antipsychotic clozapine in hippocampal poly I:C-challenged neurons. Primary hippocampal neuronal cultures were exposed to n3 PUFAs (DHA4.35 μM/EPA7.10 μM, DHA 8.7 μM/EPA14.21 μM or DHA17.4 μM/EPA28.42 μM) or clozapine (1.5 or 3 μM) in the presence or absence of poly I:C. MTT assay revealed that poly I:C-induced reduction in cell viability was prevented by n3 PUFAs or clozapine. N3 PUFAs (DHA 8.7 μM/EPA14.21 μM) or clozapine (3 μM) significantly reduced poly I:C-induced increase in iNOS, NFkB (p50/p65), IL-6 and nitrite when compared to non-treated cells. Only n3 PUFAs prevented poly I:C-induced deficits in BDNF. On the other hand, poly I:C caused a marked reduction in DCX immunoexpression, which was prevented only by clozapine. Thus, n3 PUFAs and clozapine exert in vitro neuroprotective effects against poly I:C immune challenge in hippocampal neurons, by mechanisms possibly involving the inhibition of canonical NFkB pathway. The present study adds further evidences to the mechanisms underlying n3 PUFAs and clozapine neuroprotective effects against viral immune challenges. Since n3 PUFAs is a safe strategy for use during pregnancy, our results also add further evidence for the use of this supplement in order to prevent alterations induced by viral hits during this developmental period.

Effect of dietary n-3 fatty acids supplementation on fatty acid metabolism in atorvastatin-administered SHR.Cg-Leprcp/NDmcr rats, a metabolic syndrome model

The effects of cholesterol-lowering statins, which substantially benefit future cardiovascular events, on fatty acid metabolism have remained largely obscured. In this study, we investigated the effects of atorvastatin on fatty acid metabolism together with the effects of TAK-085 containing highly purified eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) ethyl ester on atorvastatin-induced n-3 polyunsaturated fatty acid lowering in SHR.Cg-Lepr^cp/NDmcr (SHRcp) rats, as a metabolic syndrome model. Supplementation with 10mg/kg body weight/day of atorvastatin for 17 weeks significantly decreased plasma total cholesterol and very low density lipoprotein cholesterol. Atorvastatin alone caused a subtle change in fatty acid composition particularly of EPA and DHA in the plasma, liver or erythrocyte membranes. However, the TAK-085 consistently increased both the levels of EPA and DHA in the plasma, liver and erythrocyte membranes. After confirming the reduction of plasma total cholesterol, 300mg/kg body weight/day of TAK-085 was continuously administered for another 6 weeks. Supplementation with TAK-085 did not decrease plasma total cholesterol but significantly increased the EPA and DHA levels in both the plasma and liver compared with rats administered atorvastatin only. Supplementation with atorvastatin alone significantly decreased sterol regulatory element-binding protein-1c, Δ5- and Δ6-desaturases, elongase-5, and stearoyl-coenzyme A (CoA) desaturase-2 levels and increased 3-hydroxy-3-methylglutaryl-CoA reductase mRNA expression in the liver compared with control rats. TAK-085 supplementation significantly increased stearoyl-CoA desaturase-2 mRNA expression. These results suggest that long-term supplementation with atorvastatin decreases the EPA and DHA levels by inhibiting the desaturation and elongation of n-3 fatty acid metabolism, while TAK-085 supplementation effectively replenishes this effect in SHRcp rat liver.

Protective roles of N-benzylcinnamide on cortex and hippocampus of aged rat brains

Brain aging has been associated with oxidative stress leading to inflammation and apoptosis. The protective effects and underlying mechanisms of N-benzylcinnamide (PT-3), purified from Piper submultinerve, on brains of 90-week-old Wistar rats were investigated following daily intraperitoneal injection with 1.5 mg of PT-3/kg of body weight for 15 days. PT-3 treatment improved spatial learning and memory of aged rats and caused significant changes in brain frontal cortex, hippocampus, and temporal cortex in parameters associated with oxidative stress (decreased reactive oxygen species production and iNOS and nNOS levels), inflammation (reduced levels of IL-1β and IL-6), apoptosis (reduced levels of Bax and activated caspase-3, and elevated level of Bcl-2), and signaling pathways related to inflammation and apoptosis (decreased amounts of phospho-JNK and -p38, increased phospho-Akt level and no change in phospho-ERK1/2 content) compared to controls. PT-3 treatment also inhibited aged rat brain AChE activity. These results suggest that PT-3 with its intrinsic antioxidant and AChE inhibitory properties has therapeutic potential in ameliorating, in part, age-associated damages to the brain.

Omega-3 polyunsaturated fatty acids and brain aging

PURPOSE OF REVIEW

The literature on the influence of dietary omega-3 polyunsaturated fatty acid (ω-3 PUFA) on brain aging has grown exponentially during the last decade. Many avenues have been explored but no global picture or clear evidence has emerged. Experimental studies have shown that ω-3 PUFA is involved in many neurobiological processes that are involved in neurotransmission and neuroprotection, indicating that these PUFAs may prevent age-related brain damage. Human studies have revealed only a weak link between ω-3 PUFA status and cognitive aging, whereas interventional studies have yet to confirm it. The purpose of this review is to analyze the developments in the area during the last 2 years.

RECENT FINDINGS

Human brain MRI studies have confirmed previous findings that ω-3 PUFA can protect the brain during aging; two intervention studies obtained clear evidence. We also analyzed the experimental data clarifying the involvement of ω-3 PUFA in neurotransmission, neuroprotection (including prevention of peroxidation, inflammation, and excitotoxicity), and neurogenesis, thereby helping the brain cope with aging.

SUMMARY

These recent human and experimental studies provide support for and clarification of how ω-3 PUFA protect against brain aging and highlight the main lines for future research.

Omega-3 polyunsaturated fatty acids improve mitochondrial dysfunction in brain aging--impact of Bcl-2 and NPD-1 like metabolites

The present study investigated the effects of orally administered long chain omega-3 polyunsaturated fatty acids (PUFA) on mitochondrial function and processing of the amyloid precursor protein (APP) in brains of young (3 months old) and aged (24 months old) NMRI-mice. Neuroprotective properties of fish oil (FO) (1.6 ml/kg p.o.) were assessed ex vivo after 21 days in dissociated brain cells (DBC) and isolated mitochondria. Docosahexaenoic acid (DHA) levels were significantly lower in blood and brains of aged mice which were compensated by FO administration. Isolated DBC and mitochondria from aged mice showed significantly lower adenosine triphosphate (ATP) levels and reduced activity of complexes I+II and IV of the mitochondrial respiration system, respectively. FO restored the age-related decrease in respiration and improved ATP production. Moreover, FO increased the levels of anti-apoptotic Bcl-2 protein. Cell membrane fractions isolated from the brain of aged mice exhibited lower membrane fluidity, which was partially improved under FO treatment. In comparison to young animals, levels of neuroprotective sAPPα were significantly lower in the brain of aged mice. However, levels of sAPPα, Aβ and C-terminal APP fragments (CTF) were largely unchanged after FO treatment in aged mice. Neuroprotectin D-1 (NPD-1) represents a neuroprotective compound that is derived from unesterified DHA. Levels of NPD1-like metabolites (NPD1-like) and of unesterified DHA were significantly increased in brains of aged mice. FO treatment further strongly increased NPD1-like levels indicating an accelerated conversion rate of free DHA to NPD1-like. Our findings provide new mechanisms underlying the neuroprotective actions of omega-3 PUFA and identified FO as a promising nutraceutical to delay age-related mitochondrial dysfunction in the brain.

A double-blind, rct testing beneficial modulation of BDNF in middle-aged, life style-stressed subjects: a clue to brain protection?

INTRODUCTION

The aim of this prospective study was to see whether LD-1227, a quality-controlled marine nutraceuticals shown to protect experimental stress-induced hyppocampal degeneration, could beneficially modulate BDNF, as measured in the serum, in otherwise healthy but work-stressed individuals.

MATERIALS AND METHODS

Forty-eight men and women between the ages of 38 and 62 reporting high-demanding work activity but with an overall positive attitude towards their personal life were recruited. Subjects were divided in two group (24 patients each) and blindly supplemented for 2 month with: a) LD-1227 400mg or b) placebo. A third group of healthy non-stressed subjects was used as well. Blood samples were taken before and after the supplementation period. Unstimulated saliva was collected and tested for amylase while serum levels were used to measure BDNF. State Trait Anxiety Inventory (STAI), Pittsburgh Sleep Quality Index (PSQI) and psychological well-being assessment (PSWB) were measured too. Patients with Val66Met functional polymorphism of BDNF excluded those given their reported association with an impaired release of BDNF.

RESULTS

RESULTS showed that, as compared to healthy, non-stressed individuals, stressed ones has a trend decrease of BDNF and this was significantly increased by LD 12-1227 supplementation and the same inverse phenomenon occurred to salivary amylase (p<0.05). No change was noted in the PSQI score but, either STAI or PSWB tests scored better in LD-1227 supplemented subjects.

CONCLUSION

The present data suggest that LD-1227 is beneficially affecting neuromodulation and related symptoms during common stressful life conditions and may have the potential as tools in a neuroprotective clinical strategy.