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IMMUNITY
AND AUTOIMMUNITY AND FASTING |
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2004
Department of Hygiene, Hirosaki University
School of Medicine, Aomori, Japan.
AIM: A preliminary study to investigate
the combined effects of dietary restriction and weight
reduction through exercise on markers of immune function
in college judoists before and after a single competition.
METHODS: Forty-nine judoists participated in the study.
Thirty-eight athletes combined exercise and dietary restriction
(WR group), and 11 athletes did not require dietary restriction
(EX group). Changes in anthropometric parameters, energy
intake, concentrations of serum immunoglobulins and complements,
and white blood cell counts were assessed at 4 time points:
20 days (pre-values), 4 days and 1 day before the competition,
and 7 days after the competition. RESULTS: Compared with
pre-values, the WR group exhibited significant decreases
in body weight (-2.8 kg at 1 day before) and fat free
mass (-1.7 kg at 1 day before); there were no changes
in these variables in the EX group. The WR group exhibited
significant decreases in IgG, IgM and C3 at 7 days after
the competition (all p<0.01). In the EX group, significant
decreases in IgM and C3 (both p<0.05) were observed
at 7 days after the competition, though to a lesser degree
than in the WR group. CONCLUSIONS: Energy restriction
seemed to exacerbate alterations in immune markers such
as immunoglobulin and complement induced by vigorous exercise
at 7 days after a competition. Although the changed values
were still within normal limits, we hypothesize that the
potential cumulative effect of these changes over many
competitions in 1 year might well induce abnormal levels
with a possibly harmful clinical effect on judoists.
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Division of Nutritional Sciences,
The University of Texas at Austin, Austin, TX 78712, USA.
Dietary restriction is beneficial
in preventing a multitude of diseases, many of which may
involve the immune system in their etiology. Recent reports
examining dietary restriction focused on T lymphocytes
and macrophages. Dietary restriction delays the onset
of T-lymphocyte-dependent autoimmune disease; this may
be attributed to improved antioxidant defense mechanisms,
blunting shifts in T-lymphocyte subset proportions and
preventing DNA mutation frequencies. The beneficial effects
of dietary restriction were shown in both the CD4 and
CD8 T-lymphocyte subsets as well as in various immune
compartments such as the spleen, mesenteric lymph nodes,
peripheral blood, thymus, and salivary glands. In contrast,
dietary restriction may have negative effects on macrophage
function because recent evidence showed that dietary restriction
rendered mice more susceptible to peritonitis and stimulated
macrophages produced lower amounts of cytokines. The application
of dietary restriction regimens to humans would be difficult;
however, understanding the biochemical and molecular targets
of dietary restriction in the immune system may lead to
the development of new dietary strategies to delay or
prevent the onset of aging, cancer, and autoimmune disease.
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Department of Physiology and Nutrition,
University of Navarra, 31008 Pamplona, Spain.
Impaired immune function linked
to obesity has been shown in both human and animal studies.
The purpose of this work was to evaluate the effects of
a 4-week energy restriction (50% of total energy intake)
on immune function in previously diet-induced (cafeteria)
overweight rats. Flow cytometric analysis revealed that
the number of spleen T helper cells were significantly
(P < 0.05) elevated in control and overweight energy-restricted
rats as compared with groups fed ad libitum groups. The
proliferative response of splenocytes to phytohaemaglutinin
and concanavalin A from overweight rats after energy restriction
was significantly (P < 0.05) higher compared to overweight
nonrestricted rats. The cytotoxic activity of natural
killer cells tended to be lower in overweight rats compared
to controls. Finally, control rats under the dietary deprivation
period presented higher levels of uncoupling protein 2
mRNA and lower levels of leptin receptor mRNA compared
with the reference control group. These results suggest
that energy restriction is able to restore, at least in
part, the impaired immune response commonly observed in
overweight animals.
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1998
Nutritional Immunology Laboratory,
Jean Mayer USDA Human Nutrition Research Center on Aging,
Tufts University, 711 Washington Street, Boston, MA 02111,
USA.
OBJECTIVE: The immunologic effects
of isocaloric reduced- and low-fat diets and a voluntary
calorie-restricted low-fat diet resulting in weight loss
were compared to the immunologic effects of an average
American diet in hyperlipidemic individuals. METHODS:
Ten hyperlipidemic subjects were studied during three
six-week weight maintenance phases: baseline (BL) [35%
fat [14% saturated fat (SFA), 13% monounsaturated fat
(MUFA), 8% polyunsaturated fat (PUFA)] and 147 mg cholesterol
(C)/1000 kcal], reduced-fat (RF) [26% fat (4% SFA, 11%
MUFA, 11% PUFA) and 45 mg C/1000 kcal], and low-fat (LF)
[15% fat (5% SFA, 5% MUFA, 3% PUFA) and 35 mg C/1000 kcal]
diets followed by 12-week, low-fat calorie reduced phase
(LFCR). RESULTS: During the last phase, the subjects'
weight significantly decreased (p = 0.005). Cholesterol
levels were significantly reduced during all phases, compared
to BL diet (p < 0.05). Delayed-type hypersensitivity
(DTH) was assessed using Multi-test CMI. Maximum induration
diameters were 22.7, 25.4, 30.5, 34.5 mm for BL, RF, LF
and LFCR diets, respectively. Subjects on the LFCR diets
had significantly higher DTH compared to the BL diet (p
= 0.005). No significant effect of diet was observed on
lymphocyte proliferation or interleukin (IL)-1, IL-2 and
prostaglandin (PG) E(2) production. CONCLUSIONS: These
data suggest that low-fat diets (15% energy), under conditions
which result in weight loss, do not compromise and may
enhance the immune response of middle-aged and elderly
hyperlipidemic subjects. The results of this study provide
support for the hypothesis that moderate caloric restriction
in humans may have a beneficial effect on cell-mediated
immunity such as those reported in calorie-restricted
rodents.
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1998
Jackson Laboratory, Bar Harbor, Maine,
USA.
Age-related changes in peripheral
blood, spleen, and thymus of ad libitum (AL)-fed and dietary
restricted (DR) C57BL/6J x CBA/CaH-T6/J F1 (B6CBAT6 F1)
mice at young (3 mo), middle (16 mo), and old (30 mo)
ages were studied to define how dietary restriction retards
immune aging. Dietary restriction at 25% AL intake level
initiated at weaning significantly reduced the rates of
age-related declines in peripheral blood T helper cells,
naive T helper cells, and naive cytotoxic T lymphocytes
(CTLs). As a result, concentrations of these cell types
in old DR mice were equivalent to 161%, 176%, and 250%
of those in old AL controls. Dietary restriction also
abolished age-related splenomegaly and decreased total
splenocyte numbers in old DR mice. Dietary restriction
did not prevent age-related decline in thymus size, but
preserved thymus cellularity in old mice. Old DR mice
had twice as many total thymocytes and 2.6 times as many
CD4+CD8+ immature thymocytes as old AL controls. The correlations
between total immature thymocytes and concentrations of
circulating naive T helper cells and naive CTLs increase
with age and become significant in old mice. Thus, dietary
restriction preserves immature T-cell precursors in the
thymus during aging to maintain higher concentrations
of circulating T helper and naive T cells in peripheral
blood.
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1997
Department of Psychosomatic Medicine,
Faculty of Medicine, Kyushu University, Fukuoka, Japan.
We investigated changes in the
immunoendocrine system during fasting. Ten hospitalized
patients aged 14-46 y with psychosomatic disorders fasted
for 7 or 10 d. Blood samples were collected before and
on days 3 and 7 of the 7-d fasts. When fasting continued
to 10 d, an additional sample was taken on day 10. We
measured blood cellularity (white blood cells and total
lymphocytes), the total number and percentage of lymphocyte
subsets (CD2, CD3, CD4, CD8, and CD19), natural killer
(NK) cell activity, cytokines (interleukin 1 beta, interleukin
2, interleukin 6, granulocyte-macrophage colony stimulating
factor, tumor necrosis factor alpha, and interferon gamma),
and soluble interleukin 2 receptors. Corticotropin, cortisol,
and dehydroepiandrosterone sulfate (DHEAS) concentrations
were also determined. Although the total number of lymphocytes
decreased during fasting, NK cell activity increased significantly.
Plasma cortisol and DHEAS concentrations also increased
significantly whereas changes in corticotropin concentrations
were not significant. The total number and percentage
of CD4 cells decreased significantly during fasting but
no other lymphocyte subsets changed significantly. The
percentage of CD4 cells was negatively correlated with
cortisol concentrations during fasting. No detectable
changes occurred in cytokines or soluble interleukin 2
receptors during the study. All measured immunoendocrine
values that changed during fasting returned to prefasting
values during the refeeding period. These findings indicate
that fasting affects immune variables such as T cell subsets
and NK cell activity at least in part through changes
in adrenal gland-related hormones.
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1992
Faculty of Medicine, Kyushu University,
Fukuoka, Japan.
Chronic energy intake restriction
(CEIR) prolonged the median life span and inhibited autoimmunity
and development of autoimmune disease in BXSB mice, as
has been established for mice of several other autoimmune-prone,
short-lived strains. Whether imposed just after weaning
or delayed until manifestations of disease had appeared,
CEIR inhibited or reversed development of autoimmunity
and immune complex-based renal disease in male BXSB mice.
CEIR also prevented the formation of anti-DNA antibodies
and prevented the increase in circulating immune complex
levels that is typically observed in male mice of this
strain. Moreover, CEIR inhibited development of splenomegaly
and prevented the normal age-associated decline of a number
of immunological functions, including interleukin 2 production,
cell-mediated cytotoxic responses, and mixed lymphocyte
reactivity. The observed improvement in cell-mediated
immune responses was attributed largely to the capacity
of CEIR to inhibit development of the splenomegaly that
occurs concomitant with expansion of a non-T, non-B lymphoid
cell population. These findings emphasize that CEIR, even
when imposed relatively late in life in BXSB mice, can
influence _expression of autoimmunities and autoimmune
diseases of different genetic origins and presumed pathogenetic
bases.
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Department of Veterinary Pathobiology,
University of Illinois, 2001 S. Lincoln Avenue, Urbana,
IL 61802, USA.
Vet Immunol Immunopathol 2001 Sep
28;82(1-2):57-71 While aging studies employing a cross-sectional
design have been informative in documenting many age-related
alterations in immune function between different age cohorts
within a population, longitudinal studies are invaluable
for verifying changes at the level of the individual and
for defining the precise periods of life during which
particular changes occur. In the present study, a battery
of immunological parameters were evaluated in a group
of Labrador Retrievers as part of a comprehensive longitudinal
aging study. Twenty-three dogs (14 females, 9 males; from
4 to 11 years of age) were evaluated annually for total
WBC counts, lymphocyte subset distributions, natural killer
cell activity and neutrophil phagocytic activity, and
biannually for lymphoproliferative activity. An age-related
decline in absolute numbers of lymphocytes, T-cells, CD4-cells
and CD8-cells was observed in both genders. The distribution
of lymphocyte subsets shifted with age, most dramatically
in the females; percentages of B-cells declined while
those of T-cells increased. Changes in percentages of
CD4- and CD8-cells over the 8-year period were not dramatic;
in females, percentages of CD8-cells increased significantly
in early- to mid-life and then stabilized. Lymphoproliferative
responses to mitogens declined over time in both genders.
Males demonstrated higher levels of NK cytolytic activity
than females; a marginal decline in activity with age
was observed. No significant age-related changes in the
phagocytic capacity of PMN were observed. These longitudinal
findings help to discriminate between those immune parameters
which change most dramatically in early-life versus those
which either change more dramatically later in life or
change gradually over the entire span of life. In addition
they identify significant gender differences in several
parameters and corroborate our previously published cross-sectional
aging data in the same specie.
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1984
Mice of the autoimmune, lymphoproliferative
strain MRL/lpr and the congenic, nonlymphoproliferative
strain MRL/n were fed one of six diets from weaning on-ward.
These mice were sacrificed at 3 or 5 months of age. Low
fat diets resulted in lower cholesterol and higher triglyceride
levels than did cholesterol-containing high-fat diets.
Caloric restriction of MRL/lpr mice was associated with
an increased plaque-forming cell response to trinitrophenylated
polyacrylamide beads, less lymphoproliferation, and less
severe glomerulonephritis. Diet did not affect the incidence
of autoimmune vasculitis in MRL/lpr mice sacrificed at
5 months. MRL/lpr mice fed a low-fat, calorically restricted
diet from 5 months of age to death lived longer than mice
which were fed ad libitum a cholesterol-containing, high-fat
diet. At death, MRL/lpr mice fed the former diet had the
autoimmune vasculitis which had been evident in mice killed
at 5 months, whereas mice fed the latter diet, in addition
to the vasculitis, had a high incidence of atherosclerotic
lesions of intrarenal and aortic branch arteries.
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1978
NZB X NZW F1 mice initiated on calorie
restriction at weaning or at 4 to 5 months of age or initiated
on moderate protein restriction at weaning, were afforded
significant protection from the development of immune
nephritis. Whereas animals on normal calorie intake demonstrated
deposition of immune reactants in glomerular basement
membrane-oriented pattern, those on either protein or
calorie restriction exhibited mesangial confinement of
immunoglobulins and complement. Associated with these
divergent patterns of immune deposition, mice on normal
calorie intake evidence extensive cellular proliferation
and glomerular sclerosis while dietary restricted mice
demonstrated virtually no hyalinization and only mild
cellular proliferation. Autoantibody formation of calorie-restricted
animals was significantly decreased compared to mice fed
a normal diet. Thus, moderate dietary restriction may
serve as either a prophylactic or effective therapeutic
approach to ongoing autoimmune disease.
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