Activation of Cell-mediated Immunity by Morinda citrifolia Fruit Extract and Its Constituents

Morinda citrifolia, commonly known as noni, is a traditional natural medicine in French Polynesia and Hawaii. Functional foods derived from M. citrifolia fruit have been marketed to help prevent diseases and promote good health. The objective of this study was to assess the effects of M. citrifolia fruit on cell-mediated immunity. In the picryl chloride-induced contact dermatitis test, M. citrifolia fruit extract (Noni-ext) inhibited the suppression of cell-mediated immunity by immunosuppressive substances isolated from freeze-dried ascites of Ehrlich carcinoma-bearing mice (EC-sup). In addition, Noni-ext inhibited reduction of IL-2 production in EC-sup-treated mice and activated natural killer cells in normal mice. These results suggest that Noni-ext has multiple effects on the recovery of cell-mediated immunity. Furthermore, we investigated the active principles of Noni-ext and identified an iridoid glycoside, deacetylasperulosidic acid. Oral administration of deacetylasperulosidic acid inhibited the reduction of ear swelling, and also cancelled the suppression of IL-2 production along with the activation of natural killer cells in the same manner as that of Noni-ext.

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Chapter 27. Natural Killer Cells: Role in Cell-Mediated Immunity

Annual Reports in Medicinal Chemistry ◽

10.1016/s0065-7743(08)60782-4 ◽

1983 ◽

pp. 265-273

Author(s):

Ronald H. Goldfarb ◽

Michael J. Berendt

Keyword(s):

Natural Killer Cells ◽

Natural Killer ◽

Cell Mediated Immunity ◽

Killer Cells

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Effect of SLS-2 spaceflight on immunologic parameters of rats

Journal of Applied Physiology ◽

10.1152/jappl.1996.81.1.178 ◽

1996 ◽

Vol 81 (1) ◽

pp. 178-182 ◽

Cited By ~ 40

Author(s):

A. Lesnyak ◽

G. Sonnenfeld ◽

L. Avery ◽

I. Konstantinova ◽

M. Rykova ◽

...

Keyword(s):

Bone Marrow ◽

Natural Killer Cells ◽

Natural Killer ◽

T Lymphocyte ◽

Time Course ◽

Interleukin 2 ◽

Tnf Alpha ◽

Target Cells ◽

Cell Mediated Immunity ◽

Killer Cells

During the Spacelab Life Sciences-2 mission, rats were dissected in space and biosamples were returned to Earth for analysis. Immunologic studies addressed the kinetics of T lymphocyte proliferative responses, cytotoxic activity of natural killer cells, and cytokine production. Experiments were performed by using spleen and bone marrow of rats dissected before flight, during flight, immediately after landing of the space shuttle (R + 0), or 14 days after landing (R + 14), as well as those of respective control animals. Each group consisted of five male Sprague-Dawley rats. It was demonstrated that T lymphocyte activity of rats dissected in flight was significantly decreased compared with the controls. This was observed during 48-, 72-, and 96-h cultivation and stimulation with the following mitogenic stimuli: concanavalin A (Con A; 0.1, 1.0, and 10.0 mg/ml), phytohemagglutinin (PHA; 2.5 mg/ml), and interleukin-2 (IL-2; 1 U/ml). The cell proliferation rate in rats dissected immediately after landing did not decrease, whereas that in rats dissected at R + 14 increased. The activity of spleen natural killer cells was reduced in response to 51Cr-labeled target cells during flight (YAC-1 and K-562) and after flight (YAC-1). At R + 14, their activity returned to normal. Another technique employed to measure natural cytotoxicity, using [3H]uridine-labeled target cells and ribonuclease, did not reveal any differences between control and experimental groups. In bone marrow, the activity of natural killer cells did not vary significantly. The production of IL-1, IL-2, tumor necrosis factor (TNF)-alpha, and TNF-beta in spleen cell cultures of the flight rats was reduced. At R + 0, IL-1 and TNF-beta levels remained lowered, whereas TNF-alpha was increased. At R + 0, interferon-alpha and interferon-gamma levels were diminished. In summary, cell-mediated immunity in rats was significantly suppressed during flight. The time course variation of immune parameters after flight suggests that the changes may truly indicate a response of the immune system to spaceflight conditions that could increase over time.

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