Micronutrients and immune function: some recent developments.

D I Thurnham

doi:10.1136/jcp.50.11.887

Home/Archive/PubMed

PubMed · 9462235

Micronutrients and immune function: some recent developments.

D I Thurnham

View original source ↗Export metadata ↓

Abstract

Micronutrient deficiencies probably have few direct effects on the functioning of immune cells. The main effect appears to be a reduction in cell mass that may indirectly affect immune cell function, particularly where T helper cell numbers are reduced. Results of many human studies are contradictory. Some of this contradiction may be accounted for by the fact that disease may lower concentrations of micronutrients in plasma that may be misinterpreted as deficiency. Low plasma vitamin A concentrations however appear to impair immune responsiveness and have deleterious effects on membrane integrity and mucosal function. Zinc may have similar effects on gut integrity and appears to be particularly useful in the treatment of acute diarrhoea. Low concentrations of other nutrients such as ascorbate and iron, may not necessarily impair immune function. Low plasma ascorbate may assist the removal of iron from plasma and low iron concentrations appear to increase the cytotoxicity of macrophages.

Explore related subjects

Acute-Phase Reaction Animals Ascorbic Acid Deficiency Humans Immunocompetence Iron Micronutrients Vitamin A Deficiency Zinc Journal Article Review

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

D I Thurnham. 1997. Micronutrients and immune function: some recent developments.. https://doi.org/10.1136/jcp.50.11.887

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2001

Apolipoprotein A-I inhibits the production of interleukin-1beta and tumor necrosis factor-alpha by blocking contact-mediated activation of monocytes by T lymphocytes.

Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), essential components in the pathogenesis of immunoinflammatory diseases, are strongly induced in monocytes by direct contact with stimulated T lymphocytes. This study demonstrates that adult human serum (HS) but not fetal calf or cord blood serum displays inhibitory activity toward the contact-mediated activation of monocytes by stimulated T cells, decreasing the production of both TNF-alpha and IL-1beta. Fractionation of HS and N-terminal microsequencing as well as electroelution of material subjected to preparative electrophoresis revealed that apolipoprotein A-I (apo A-I), a "negative" acute-phase protein, was the inhibitory factor. Functional assays and flow cytometry analyses show that high-density lipoprotein (HDL)-associated apo A-I inhibits contact-mediated activation of monocytes by binding to stimulated T cells, thus inhibiting TNF-alpha and IL-1beta production at both protein and messenger RNA levels. Furthermore, apo A-I inhibits monocyte inflammatory functions in peripheral blood mononuclear cells activated by either specific antigens or lectins without affecting cell proliferation. These results demonstrate a new anti-inflammatory activity of HDL-associated apo A-I that might have modulating functions in nonseptic conditions. Therefore, because HDL has been shown to bind and neutralize lipopolysaccharide, HDL appears to play an important part in modulating both acute and chronic inflammation. The novel anti-inflammatory function of apo A-I reported here might lead to new therapeutic approaches in inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, and atherosclerosis.

Acute-Phase Reaction↗

PubMed2001

Acute phase response during radiotherapy.

PURPOSE: The acute phase response is characterized by changes in the plasma concentrations of a number of liver-synthesized proteins, one of which is C-reactive protein (CRP). The existence of these changes in the plasma profile underlies the change in erythrocyte sedimentation rate (ESR). Acute phase response itself is an illness and may result from immunologic reactions and inflammatory processes. This study is designed to determine whether the CRP level and ESR increase during radiotherapy and whether their rise correlates with acute and late radiation morbidity. METHODS AND MATERIALS: Between April 1997 and October 1998, 51 patients with the diagnosis of endometrium and cervical cancer were treated with surgery and postoperative radiotherapy. Median age at the time of radiotherapy was 52 (range, 26-73) years. Thirty patients received pelvic radiotherapy, and 21 patients were treated by pelvic-paraaortic irradiation. A total dose of 50.4 Gy to the pelvis and 45 Gy to the paraaortic field were delivered in conventional fraction. Erythrocyte sedimentation rates and CRP levels were studied before, during, and at the end of radiotherapy. RESULTS: The mean ESR measurements before and after radiotherapy were 40 (8-100) and 52 (10-120), and mean CRP levels were 1.4 (0.12-9.8) and 2.7 (0.12-32.2), respectively. The statistical analysis yielded significant rise in ESR and CRP levels at the end of radiotherapy (p < 0.001). The increase was more prominent in patients who were irradiated through pelvic-paraaortic field than in patients with pelvic radiation (p = 0.005 and 0.028 respectively). CONCLUSION: Acute phase response was present during radiotherapy. Radiotherapy should be considered as a cause of increase in CRP level and ESR especially in clinical conditions where acute phase response is important.

Acute-Phase Reaction↗

PubMed2001

Prospective evaluation of the systemic immune response following abdominal, vaginal, and laparoscopically assisted vaginal hysterectomy.

BACKGROUND: Alterations in serum levels of cytokine interleukin-6 (IL-6) and acute-phase protein C-reactive protein (CRP) correlate directly with extent of tissue damage and inflammatory reaction. We therefore prospectively compared the postoperative levels of IL-6 and CRP following abdominal (AH), vaginal (VH), and laparoscopically assisted vaginal hysterectomy (LAVH). METHODS: A total of 29 patients were included in the study (10 VH, 10 LAVH, 9 AH). Nine blood samples were taken from each patient at various time points before, during, and after surgery. CRP and IL-6 were measured under standardized conditions using ELISA and turbidometry. RESULTS: Preoperative levels of IL-6 and CRP were low in all three patient groups. There was a significant increase in the IL-6 level in patients undergoing AH at the time of peritoneal closure that reached a maximum 2 h postoperatively and remained significantly elevated for 12 h postoperatively when compared to the IL-6 levels of patients undergoing VH or LAVH (p < 0.05). The levels of the IL-6 time courses differed significantly among the three operative procedures (p = 0.013). In contrast, the levels of the CRP time courses did not differ significantly (p = 0.066); however, CRP expression was elevated 36 h postoperatively in patients undergoing AH, as compared with those undergoing VH. CONCLUSION: Elevated IL-6 levels subsequent to AH may reflect significantly greater tissue damage in these patients than in patients who undergo VH or LAVH. LAVH should therefore be considered in cases that cannot be managed by the vaginal route alone.

Acute-Phase Reaction↗