Plasma polyunsaturated fatty acids and liver enzymes in HIV-infected subjects: the Prospective Urban and Rural Epidemiology (PURE) Study

Fatty Acids Composition and HIV Infection: Altered Levels of n-6 Polyunsaturated Fatty Acids Are Associated with Disease Progression

Fatty acids (FAs) are important regulators of immune responses and innate defense mechanisms. We hypothesized that disturbed FA metabolism could contribute to the progression of HIV infection. Plasma levels of 45 FAs were analyzed with gas chromatography in healthy controls and HIV-infected patients with regard to Mycobacterium avium complex (MAC) infection. In vitro, we assessed MAC-PPD-induced release of inflammatory cytokines in peripheral and bone marrow mononuclear cells (PBMC and BMMC) according to levels of n-6 polyunsaturated fatty acids (PUFAs). While plasma saturated FAs were higher in HIV infection, PUFAs, and in particular the n-6 PUFA arachidonic acid (AA), were lower in patients with advanced disease. The ratio between AA and precursor dihomo-γ-linolenic acid, reflecting Δ5-desaturase activity, was markedly lower and inversely correlated with plasma HIV RNA levels in these patients. Depletion of AA was observed prior to MAC infection, and MAC-PPD-induced release of TNF and IL-6 in PBMC and BMMC was lower in patients with low plasma AA. Our findings suggest that dysregulated metabolism of n-6 PUFAs may play a role in the progression of HIV infection. While high AA may contribute to chronic inflammation in asymptomatic HIV-infected patients, low AA seems to increase the susceptibility to MAC infection in patients with advanced disease.

Nutritional and Lifestyle Therapy for NAFLD in People with HIV

HIV infection and nonalcoholic fatty liver disease (NAFLD) are two major epidemics affecting millions of people worldwide. As people with HIV (PWH) age, there is an increased prevalence of metabolic comorbidities, along with unique HIV factors, such as HIV chronic inflammation and life-long exposure to antiretroviral therapy, which leads to a high prevalence of NAFLD. An unhealthy lifestyle, with a high dietary intake of refined carbohydrates, saturated fatty acids, fructose added beverages, and processed red meat, as well as physical inactivity, are known to trigger and promote the progression of NAFLD to nonalcoholic steatohepatitis, liver fibrosis, and hepatocellular carcinoma. Furthermore, with no currently approved pharmacotherapy and a lack of clinical trials that are inclusive of HIV, nutritional and lifestyle approaches still represent the most recommended treatments for PWH with NAFLD. While sharing common features with the general population, NAFLD in PWH displays its own peculiarities that may also reflect different impacts of nutrition and exercise on its onset and treatment. Therefore, in this narrative review, we aimed to explore the role of nutrients in the development of NAFLD in PWH. In addition, we discussed the nutritional and lifestyle approaches to managing NAFLD in the setting of HIV, with insights into the role of gut microbiota and lean NAFLD.

Effects of HIV Infection in Plasma Free Fatty Acid Profiles among People with Non-Alcoholic Fatty Liver Disease

Despite its high prevalence, the mechanisms underlying non-alcoholic fatty liver disease (NAFLD) in people living with HIV (PLWH) are still unclear. In this prospective cohort study, we aim to evaluate differences in plasma fatty acid profiles between HIV-infected and HIV-uninfected participants with NAFLD. We included participants diagnosed with NAFLD, both HIV-infected and HIV-uninfected. Fatty acid methyl esters were measured from plasma samples. Ratios ([product]/[substrate]) were used to estimate desaturases and elongases activity. We used linear regression for adjusted analyses. We included 31 PLWH and 22 HIV-uninfected controls. We did not find differences in the sum of different types of FA or in FA with a greater presence of plasma. However, there were significant differences in the distribution of some FA, with higher concentrations of ALA, trans-palmitoleic, and behenic acids, and a lower concentration of lignoceric acid in PLWH. PLWH had lower C24:0/C22:0 and C16:0/C14:0 ratios, which estimates the activity of elongases ELOVL1 and ELOVL6. Both groups had similar fatty acid distribution, despite differences in traditional risk factors. PLWH had a lower proportion of specific ratios that estimate ELOVL1 and ELOVL6 activity, which had been previously described for other inflammatory conditions, such as psoriasis.

DHA supplementation improved both memory and reaction time in healthy young adults: a randomized controlled trial

BACKGROUND

Docosahexaenoic acid (DHA) is important for brain function, and its status is dependent on dietary intakes. Therefore, individuals who consume diets low in omega-3 (n-3) polyunsaturated fatty acids may cognitively benefit from DHA supplementation. Sex and apolipoprotein E genotype (APOE) affect cognition and may modulate the response to DHA supplementation.

OBJECTIVES

We investigated whether a DHA supplement improves cognitive performance in healthy young adults and whether sex and APOE modulate the response.

DESIGN

Healthy adults (n = 176; age range: 18-45 y; nonsmoking and with a low intake of DHA) completed a 6-mo randomized, placebo-controlled, double-blind intervention in which they consumed 1.16 g DHA/d or a placebo. Cognitive performance was assessed by using a computerized cognitive test battery. For all tests, z scores were calculated and clustered into cognitive domains as follows: episodic and working memory, attention, reaction time (RT) of episodic and working memory, and attention and processing speed. ANCOVA was conducted with sex and APOE as independent variables.

RESULTS

RTs of episodic and working memory improved with DHA compared with placebo [mean difference (95% CI): -0.18 SD (-0.33, -0.03 SD) (P = 0.02) and -0.36 SD (-0.58, -0.14 SD) (P = 0.002), respectively]. Sex × treatment interactions occurred for episodic memory (P = 0.006) and the RT of working memory (P = 0.03). Compared with the placebo, DHA improved episodic memory in women [0.28 SD (0.08, 0.48 SD); P = 0.006] and RTs of working memory in men [-0.60 SD (-0.95, -0.25 SD); P = 0.001]. APOE did not affect cognitive function, but there were some indications of APOE × sex × treatment interactions.

CONCLUSIONS

DHA supplementation improved memory and the RT of memory in healthy, young adults whose habitual diets were low in DHA. The response was modulated by sex. This trial was registered at the New Zealand Clinical Trials Registry (http://www.anzctr.org.au/default.aspx) as ACTRN12610000212055.

The New Zealand PUFA semiquantitative food frequency questionnaire is a valid and reliable tool to assess PUFA intakes in healthy New Zealand adults

The health benefits of PUFA are well established. There is no valid tool or complete fatty acid database to assess PUFA intake in New Zealand (NZ). This study aimed to develop, validate, and test the reproducibility of a NZ-specific PUFA FFQ. A semiquantitative NZ PUFA FFQ was developed based on a validated Australian PUFA FFQ. The Australian fatty acid database was adapted to include NZ-specific data for major PUFA sources. Healthy participants from Auckland, NZ (n = 48) provided fasting blood samples for erythrocyte PUFA analysis, completed the NZ PUFA FFQ and a 3-d weighed food record (WFR), and repeated the NZ PUFA FFQ 3 mo later (n = 42). Relative validity was evaluated by assessing the triangular relationship among the NZ PUFA FFQ, WFR, and erythrocyte PUFA using the methods of triads [EPA, DHA, total omega-3 (n-3) long-chain (LC) PUFA only] and by comparing, correlating, cross-classifying into quintiles and assessing agreement using Bland-Altman plots of intakes between the NZ PUFA FFQ and WFR. Reproducibility was assessed by comparing and correlating intakes between repeat administrations of the NZ PUFA FFQ. The NZ PUFA FFQ effectively estimated EPA [ρ(QT) = 0.72 (95% CI: 0.49, 0.89)], DHA [ρ(QT) = 0.72 (95% CI: 0.53, 0.95)], and total (n-3) LCPUFA [ρ(QT) = 0.68 (95% CI: 0.47, 0.89)] intakes and was comparable with the WFR for other PUFA except docosapentaenoic acid. Repeated implementation of the NZ PUFA FFQ showed agreement for PUFA intakes. The NZ PUFA FFQ is a valid and reliable tool to measure PUFA intake in healthy NZ adults.

Altered lipid concentrations of liver, heart and plasma but not brain in HIV-1 transgenic rats

Disturbed lipid metabolism has been reported in antiretroviral-naive HIV-1-infected patients suggesting a direct effect of the virus on lipid metabolism. To test that the HIV-1 virus alone could alter lipid concentrations, we measured these concentrations in an HIV-1 transgenic (Tg) rat model of human HIV-1 infection, which demonstrates peripheral and central pathology by 7-9 months of age. Concentrations were measured in high-energy microwaved heart, brain and liver from 7-9 month-old HIV-1 Tg and wildtype rats, and in plasma from non-microwaved rats. Plasma triglycerides and liver cholesteryl ester and total cholesterol concentrations were significantly higher in HIV-1 Tg rats than controls. Heart and plasma fatty acid concentrations reflected concentration differences in liver, which showed higher n-3 and n-6 polyunsaturated fatty acid (PUFA) concentrations in multiple lipid compartments. Fatty acid concentrations were increased or decreased in heart and liver phospholipid subfractions. Brain fatty acid concentrations differed significantly between the groups for minor fatty acids such as linoleic acid and n-3 docosapentaenoic acid. The profound changes in heart, plasma and liver lipid concentrations suggest a direct effect of chronic exposure to the HIV-1 virus on peripheral lipid (including PUFA) metabolism.

Consumption of salmonv.salmon oil capsules: effects onn-3 PUFA and selenium status

Salmon provides long-chain (LC)n-3 PUFA and Se, which are well recognised for their health benefits. Then-3 and Se status of the New Zealand population is marginal. The objective of the present study was to compare the effects of consuming salmonv.supplementation with salmon oil on LCn-3 and Se status. Healthy volunteers (n44) were randomly assigned to one of four groups consuming 2 × 120 g servings of salmon/week or 2, 4 or 6 salmon oil capsules/d for 8 weeks. Linear regression analysis predictive models were fitted to the capsule data to predict changes in erythrocyte LCn-3 levels with intakes of LCn-3 from capsules in amounts equivalent to that consumed from salmon. Changes in Se status (plasma Se and whole-blood glutathione peroxidase) were compared between the groups consuming salmon and capsules (three groups combined). Salmon, 2, 4 and 6 capsules provided 0·82, 0·24, 0·47 and 0·69 g/d of LCn-3 fatty acids. Salmon provided 7 μg/d and capsules < 0·02 μg/d of Se. The predictive model (r20·31,P = 0·001) showed that increases in erythrocyte LCn-3 levels were similar when intakes of 0·82 g/d LCn-3 from salmon or capsules (1·92 (95 % CI 1·35, 2·49)v.2·32 (95 % 1·76, 2·88) %) were consumed. Plasma Se increased significantly more with salmon than with capsules (12·2 (95 % CI 6·18, 18·12)v.1·57 (95 % CI − 2·32, 5·45) μg/l,P = 0·01). LCn-3 status was similarly improved with consumption of salmon and capsules, while consuming salmon had the added benefit of increasing Se status. This is of particular relevance to the New Zealand population that has marginal LCn-3 and Se status.