Dietary supplementation with lacto-wolfberry enhances the immune response and reduces pathogenesis to influenza infection in mice.

Despite the availability of vaccines, influenza is a considerable public health problem, which emphasizes the need for development of additional strategies to enhance host defense against influenza. Wolfberry, or goji berry, long used as a medicinal food in China, has recently been shown to improve immune response in mice. Because immune response plays a key role in the body's defense against pathogens, we hypothesized that wolfberry may increase host resistance to influenza infection by enhancing immune response. To test this hypothesis, we fed adult mice (4 mo old) a milk-based preparation of wolfberry called Lacto-Wolfberry (LWB) for 4 wk and then infected them with influenza A/Puerto Rico/8/34 (H1N1) while continuing the same experimental diets. Viral titer, lung pathology, and immune response were determined at different time points postinfection. LWB supplementation prevented infection-induced weight loss and reduced lung pathology on days 6 and 9 postinfection (P < 0.05). LWB-fed mice showed overall, significantly higher concanavalin A-induced IL-2 production (P < 0.05). Furthermore, we found positive correlations between weight loss and lung viral titer, pathology score, TNFα, and IL-6 production as well as negative correlations with T cell proliferation and IL-2 production (all P ≤ 0.05). These results indicate that LWB supplementation can attenuate symptoms and pathology of influenza infection by decreasing inflammatory cytokines in lungs while enhancing systemic T cell-mediated function as measured by their ability to produce IL-2.

Cardio-metabolic and immunological impacts of extra virgin olive oil consumption in overweight and obese older adults: a randomized controlled trial.

BACKGROUND: Both aging and obesity are related to dysregulated immune function, which may be responsible for increased risk of infection and also chronic non-infectious diseases. Dietary lipids have been shown to impact immune and inflammatory responses and cardio-metabolic risk factors. No information on the impact of olive oil on immune responses of overweight and obese older adults is available. OBJECTIVE: We aimed to determine the effect of replacing oils used in a typical American diet with extra virgin olive oil for 3 months on immune responses and cardio-metabolic risk factors in overweight and obese older adults. METHODS: This was a randomized, single-blinded and placebo-controlled trial in 41 overweight or obese participants (aged ≥ 65) who consumed a typical American diet. Participants in the control (CON, n = 21) group were provided with a mixture of corn, soybean oil and butter, and those in the olive oil (OO, n = 20) group, with extra virgin olive oil, to replace substitutable oils in their diet. At baseline and 3 months, we measured blood pressure, biochemical and immunological parameters using fasting blood, and delayed-type hypersensitivity (DTH) skin response. RESULTS: Compared to the CON group, the OO group showed decreased systolic blood pressure (P < 0.05), a strong trend toward increased plasma HDL-C concentrations (P = 0.06), and increased anti-CD3/anti-CD28 -stimulated T cell proliferation (P < 0.05). No differences were found in T cell phenotype, cytokine production, and DTH response between the two groups. CONCLUSIONS: Our results indicate that substitution of oils used in a typical American diet with extra virgin olive oil in overweight and obese older adults may have cardio-metabolic and immunological health benefits. This trial was registered at clinicaltrials.gov as NCT01903304.