Caffeic acid phenethyl ester inhibits nuclear factor-kappaB and protein kinase B signalling pathways and induces caspase-3 expression in primary human CD4+ T cells.

Caffeic acid phenethyl ester (CAPE), an active component in propolis, is known to have anti-tumour, anti-inflammatory and anti-oxidant properties. In this study, the effects of CAPE on the functions of primary human CD4+ T cells were evaluated in vitro. CAPE significantly suppressed interferon (IFN)-gamma and interleukin (IL)-5 production and proliferation of CD4+ T cells stimulated by soluble anti-CD3 and anti-CD28 monoclonal antibodies in both healthy subjects and asthmatic patients. CAPE inhibited nuclear factor (NF)-kappaB activation and protein kinase B (Akt) phosphorylation, but not p38 mitogen-activated protein kinase (MAPK) phosphorylation in T cells. CAPE also induced active caspase-3 expression in CD4+ T cells; CCR4+CD4+ T cells were more sensitive to CAPE induction than CXCR3+CD4+ T cells. Together, these results indicate that CAPE inhibits cytokine production and proliferation of T cells, which might be related to the NF-kappaB and Akt signalling pathways, and that CCR4+CD4+ T cells are more sensitive to CAPE inhibition. This study provides a new insight into the mechanisms of CAPE for immune regulation and a rationale for the use of propolis for the treatment of allergic disorders.

A nationwide survey on epidemiological characteristics of childhood Henoch-Schönlein purpura in Taiwan.

OBJECTIVE: To evaluate the annual incidence and other epidemiological characteristics of Henoch-Schönlein purpura (HSP) among children in Taiwan. METHODS: The records of patients were derived from the research database of the Bureau of National Health Insurance, Taiwan, Republic of China, from January 1999 to December 2002. Children younger than 17 yr of age with the diagnosis of HSP were included into this study. Data for each patient including sex, age, date of onset and length of hospitalization were recorded and analysed. RESULTS: A total of 2759 cases were included with an annual incidence of 12.9 (11.8-13.4) per 100 000 children <17 yr of age. The occurrence of HSP had a peak at the age of 5 to 6 yr. In this study, 1118 (40.5%) patients had been hospitalized at some stage. There were 1454 males and 1305 females, for a male to female ratio of 1.11. Males had a higher annual incidence before the age of 10 yr (P = 0.04), and had a lower incidence than females at older ages (P = 0.02). Disease onset was more common in autumn and winter, and no apparent change in seasonal pattern was noted over 4 yr. CONCLUSIONS: Insurance claim data provide useful information on the epidemiology of HSP in Taiwan. Childhood HSP in Taiwan, with an incidence of 12.9 per 100 000 children, occurs commonly in autumn and winter; and at the age of 5 to 6 yr. The characteristics presented in this study may provide valuable data for understanding and further studies of HSP.

Dietary fish oil increases CD8+ T-cells and decreases autoreactive T-cell activity in autoimmune NZB/W F1 mice.

To further elucidate the effect of different dietary fats on the pathogenesis of autoimmune diseases, five groups of New Zealand black/white (NZB/W) F1 mice were fed diets containing 200 g of different dietary fats including palm oil, lard-soybean oil (1:1, w/w), soybean oil, canola oil or fish oil. Serum levels of anti-DNA antibodies, proteinuria were followed every month and life span of the mice was determined. After 5 months of the respective diets, mice were killed at the age of 7 months and phenotypic analysis of splenic cells and peritoneal resident cells was performed. The pattern of production of cytokines in splenic T-cells was also investigated. The peritoneal resident cells were isolated for measurement of prostaglandin E2 (PGE2) levels. Significantly lower immunoglobulin G (IgG) anti-single-stranded DNA (ssDNA) and anti-double-stranded DNA (dsDNA) antibody levels were associated with less severe proteinuria and prolonged life span in mice fed dietary fish oil compared to mice fed other dietary oils. Phenotypic analysis of spleen cells showed increased CD8+ T-cells in the mice fed dietary fish oil compared to mice of the other dietary groups, and the percentage of natural killer (NK) cells in the mice fed dietary fish oil was also higher compared to the other dietary groups. The peritoneal resident cells produced lower PGE2 in mice fed fish oil compared to mice in the other dietary groups. To further investigate the effect of fish oil on autoreactive T-cells, splenic T-cells purified using a nylon wool column were stimulated with non-T-cells of young NZB/W F1 mice. Our data suggest that the anti-DNA antibody augmentation ability of T-cells in mice fed dietary fish oil was significantly decreased compared to mice in the other dietary groups. These data indicate that dietary fish oil might maintain the existence of CD8+ T-cells, decrease autoreactive T-cell activity and alleviate subsequent autoimmune processes in autoimmune prone NZB/W F1 mice.

Dietary oxidized oil influences the levels of type 2 T-helper cell-related antibody and inflammatory mediators in mice.

The aim of this present study was to investigate the effect of amount and degree of oxidation of dietary oil on type 2 T-helper cell (TH)-related immune responses. Four groups of BALB/c mice were fed either 50 g soyabean oil/kg (50-S), 50 g oxidized oil/kg (50-O), 150 g soyabean oil/kg (150-S) or 150 g oxidized oil/kg (150-O). After 14 weeks consuming the experimental diets, the mice were immunized with ovalbumin (OVA) plus Al and antigen-specific immunoglobulin (Ig)E, IgG1 and IgG2a, inflammatory mediators such as prostaglandin (PG) E2 and leukotriene (LT)B4 were determined. Higher hepatic microsomal cytochrome P450 was noted in mice fed 150 g oxidized oil/kg compared with those of other groups. OVA-specific IgG1 and IgE were higher in mice fed 150 g oxidized oil/kg compared with those of the other groups. The data suggested the interleukin (IL)-4: interferon (IFN)-gamma ratio was higher in mice fed 50 g dietary oxidized oil/kg compared with that of the 50-S group. The IL-5:IFN-gamma ratios were higher in the 150-S and 150-O groups than in the 50-S and 50-O groups. PGE2 and LTB4 produced by macrophages stimulated by lipopolysaccharide were highest in mice in the 150 g oxidized oil/kg group. The data suggested that an increased intake of oxidized oil might exert an unfavourable effect on the TH2 response involved in allergic disease.

Different dietary fats influence serum and tissue lipids and anti-cardiolipin antibody levels in autoimmune-prone NZB/W F1 mice.

To investigate the influence of different dietary fats on lipids and anti-cardiolipin antibody levels, autoimmune NZB/W F1 mice were fed on diets containing 200 g dietary fat as palm oil, lard-soyabean oil (1:1, w/w), soyabean oil, rapeseed oil or fish oil/kg. In addition, each dietary fat group was divided into an early-feeding group with feeding from 2 months of age, and a late-feeding group with feeding from 5 months of age. Serum levels of triacylglycerol, phospholipid, cholesterol and anti-cardiolipin antibody were measured at regular intervals, and mice were killed at the age of 7 months for analysis of hepatic lipid and fatty acids. The results showed that hepatic triacylglycerol and cholesterol contents were lower in mice fed on fish oil than in those fed on palm oil. In contrast, hepatic phospholipid content was higher in mice of the fish oil group than in those of the other four dietary fat groups. Composition profiles for both hepatic and renal oleic acid (18: 1n-9), linoleic acid (18: 2n-6) and eicosapentaenoic acid (20: 5n-3) were similar to those of the dietary fats in mice of both early-feeding and late-feeding groups. Fish oil intake decreased arachidonic acid (20: 4n-6) concentration in kidney tissue but not in liver tissue. Serum triacylglycerol, cholesterol and phospholipid levels were lower in mice fed on fish oil than in those fed on palm oil. Immunoglobulin (Ig) M anti-cardiolipin antibody was lower for the fish oil group than for the other groups. The IgG anti-cardiolipin antibody level was significantly lower in mice fed on fish oil compared with that of the palm oil group only in the early-feeding group. There was a positive correlation between serum IgM anti-cardiolipin antibody and phospholipid levels (early-feeding group r 0.902, P < 0.05; late-feeding group r 0.894, P < 0.05). These findings suggest dietary fish oil may affect both lipid levels and anti-cardiolipin antibody, contributing to alleviation of the autoimmune process in autoimmune-prone NZB x NZW F1 mice.

Influence of feeding unsaturated fats on growth and immune status of mice.

Dietary polyunsaturated fatty acids alter the lipid composition and immune systems of mice. To date, most studies have been of short duration and focused on a particular immunologic assay. Adult female mice were therefore fed diets rich in 18:1(n-9) (olive oil), 18:2(n-6) (safflower oil), 18:3(n-3) (linseed oil) or 20:5(n-3) and 22:6(n-3) (fish oil-safflower oil, 9:1, wt/wt), for a 5-mo period, encompassing two breeding cycles. Offspring from the second breeding cycle were then fed these diets for 42 d, and a spectrum of immune functions was assessed. Dietary fat had a small effect on gestational weight gain and total and relative organ weights of the offspring. The relative amounts of splenic Ly-2 and gamma delta receptor-expressing T cells were proportional to the concentration of 18:2(n-6), and inversely proportional to the concentration of long chain (n-3) polyenes in the diet. In contrast, Ly-1, immunoglobulin M, GM1+, and Ly-1 B suppressor inducer cells were not significantly affected by dietary fat. Splenic natural killer cell and lymphokine activated killer cell activities were attenuated by (n-3) polyunsaturated fatty acids, in contrast to superoxide production of stimulated macrophages which was increased. Those immune functions that were sensitive to dietary fat modulation will be the focus of continued research.