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The influence of marginal zinc
deficient diet on post-vaccination immune response against
hepatitis B in rats.
Ozgenc F, et al.
Hepatol Res. 2006; 35(1):26-30
To evaluate in vitro T lymphocyte proliferation and specific
antibody response to hepatitis B vaccination in two groups
of rats fed with normal and marginal zinc content.
Twenty-two Wistar-Albino rats were randomly assigned into
two groups and were fed with constant diet. Zinc was
supplemented 10mg/kg dry weight in group I (marginal zinc
content) (n=14) and 30mg/kg dry weight in group II (n=8).
Hepatitis B vaccine (Engerix B, 4mug) was administered
intramuscularly after 8 weeks on feeding and a booster dose
was applied 4 weeks after the first injection. Rats were
killed 3 weeks after the second injection. Peripheral blood
mononuclear cells were stimulated in vitro by PHA
(2.5mug/ml) and hepatitis B surface antigen (2.5, 5,
10mug/ml). Proliferation was evaluated by ELISA
(celltiter-96 aqueous one solution cell proliferation
assay). Serum zinc, anti-HBs titer and zinc per dry liver
weight were also measured. Two groups were compared with
respect to antigen specific antibody and lymphocyte
proliferation responses. Proliferation response to HbsAg
were expressed as net percent increase (pci) in lymphocyte
proliferation from the baseline activity. Rats' mean body
weight and weight gain per month were similar. Median serum
zinc was 39 (23-75) and 76(64-115)mug/dl of groups I and II
rats, respectively (p<0.05), while there was no difference
in liver zinc content between the two groups (37mug/g dry
weight versus 32mug/g dry weight).
Median anti-HBs levels of groups I and II were 741
(0-10,000)IU/I, 5791 (558-10,000)IU/I, respectively
(p<0.05). In lymphocyte proliferation assays, mean net pci
with HbsAg of 5 and 10mug/ml were 9.4% and 11.3% in group I
rats; while they were 25.3% and 26.1% in group II rats
(p<0.01 and p<0.01, respectively). In vitro cell- mediated
immune response and in vivo specific antibody response to
hepatitis B vaccine was decreased in rats fed a diet with
marginal zinc content.
These observations have shown that marginal Zn deficiency
might influence the efficacy of hepatitis B vaccination in
humans.
The effect of supplemental zinc on the
height and weight percentiles of children
Hakimi SM, et al.
Arch Iran Med. 2006 Apr : 9(2) :148-52.
Considering the high incidence of low weight and short
stature among Iranian children as well as the high
prevalence of both mild and moderate types of zinc
deficiency, this study was conducted among patients who were
referred to the Pediatric Clinic at Massih Daneshvari
Hospital during 1997 -1999. The aim of this study was to
determine the effect of zinc supplementation on the
children's height and weight percentiles. Age, sex, and
height and weight percentiles before and after
administration of zinc were determined and recorded. The
zinc supplement used in this project was in the form of a
zinc sulfate solution in 0.1 % and 0.5% concentrations. The
dose was the upper limit of a tolerable dose, which was
given in three divided doses per day. The serum zinc level
was measured with the atomic absorption spectrophotometry
method. The effect of age, sex, and initial serum zinc level
on the percentile changes were determined. This study was
conducted on 42 children with equal distribution of gender
(21 male and 21 female patients). The mean age was 4.9 + / -
4.1 years. Means of height and weight were 101.8 + / - 23 cm
and 16.5 +/ - 8.1 kg, respectively. The initial serum zinc
level was 85.1 +/- 31.6 microg/ dL. The duration of zinc
administration was 3.2 + /- 2.6 months. The subjects were
followed for a minimum of one month to a maximum of 10
months. The percentage of children with weight and height
percentiles below the 50th percentile was reduced from 69%
to 54% (P < 0.05) and from 50% to 33% (P < 0.01),
respectively. Also, it was noted that children with low
serum zinc levels demonstrated greater percentile changes.
It was concluded that supplemental zinc increases height and
weight percentiles.
Zinc nutrition in healthy subjects and
patients with taste impairment from the view point
of zinc ingestion, serum zinc concentration and angiotensin
converting enzyme activity
Ueda C, et al.
Auris Nasus Larynx. 2006; 33(3):283-8
To estimate the zinc
nutrition in healthy subjects and patients with taste
impairment. Dietary zinc intake, zinc concentration in
the serum and the ratio of apo/holo-activities of
angiotensin converting enzyme (ACE), a zinc dependent
enzyme in the serum (ACE ratio) were used as indices.
Healthy paramedical volunteers from a local hospital
were used as well as patients with taste impairment seen
in the Department of Otolaryngology, Tokushima
University Hospital. Dietary zinc intake was estimated
with the food frequency questionnaire (FFQ). Zinc
concentration in the serum was measured by means of
atomic absorption spectrometry. The ACE activity in the
serum was measured spectrophotometrically as the
activity of holo-ACE, which contains zinc and shows full
ACE activity. The activity of apo-ACE, which does not
contain zinc, was determined as the increase of its
activity over that of the initial holo-ACE activity
after the addition of zinc to the serum in vitro. ACE
ratio was used as a more sensitive indicator of zinc
nutrition than measuring zinc concentration in the
serum. The researchers found that there were no
differences in dietary intake of zinc after adjusting
for energy and zinc concentration in the serum between
patients and age-adjusted healthy subjects. The ACE
ratio in patients with taste impairment was
significantly higher than that in age-adjusted healthy
subjects (P<O.O5). The researchers data demonstrates
that zinc deficiency is a predominant factor in
underlying taste impairment and was hypothesized that
patients with taste impairment may have malabsorption of
dietary zinc.
Absorbability and utility of calcium
in mineral waters
Robert P Heaney
Am J Clin Nutr 2006;84:371-4.
Calcium intake in
North America remains substantially below recommended
amounts. Bottled waters high in calcium could help close
that gap. The objectives were to summarize and integrate
published absorbability and biodynamic data concerning
high-calcium mineral waters and to combine these data with
unpublished analyses from a laboratory. The usual library
database was searched. The absorbability of calcium from a
high-mineral water labeled with tracer quantities of 45Ca
was measured in human volunteers as a part of an otherwise
low-calcium test meal. Published reports that used differing
load sizes and meal conditions were harmonized by making
corrections based on published calcium absorbability data.
All the high-calcium mineral waters had absorbabilities
equal to milk calcium or slightly better. When tested, all
produced biodynamic responses indicative of absorption of
appreciable quantities of calcium (ie, increased urinary
calcium, decreased serum parathyroid hormone, decreased bone
resorption biomarkers, and protection of bone mass). Dr.
Heaney concluded that high-calcium mineral waters could
provide useful quantities of bioavailable calcium.
Magnesium and muscle performance in
older persons: the InCHIANTI study
Dominquez LJ, et al.
Am J Clin Nutr 2006;84:419-26.
The role of magnesium in maintaining muscle integrity and
function in older adults is largely unknown. The researchers
investigated the relation between serum magnesium
concentrations and muscle performance in older subjects. The
data are from the baseline examination conducted between
September 1998 and March 2000 of the InCHIANTI (aging in the
Chianti area) study, a prospective epidemiologic survey of
risk factors for late-life disability. From among 1453
randomly selected community residents completing a home
interview, 1138 men (46%) and women (aged 66.7 +/- 15.2 y;
average +/- SD) with complete data on muscle performance and
serum magnesium who were not severely cognitively
compromised and had no evidence of kidney disease or
hypercalcemia were included in the analysis. Muscle
performance was evaluated by grip strength, lower-leg muscle
power, knee extension torque, and ankle extension isometric
strength and was normalized for age and body mass index
(BMI) within each sex. After adjustment for age, sex, BMI,
laboratory variables, presence of chronic diseases, muscle
area, muscle density, and physical activity level, serum
magnesium concentrations were significantly associated with
indexes of muscle performance, including grip strength (β =
2.0 +/- 0.5, P = 0.0002), lowerleg muscle power (β = 8.8 +/-
2.7, P = 0.001), knee extension torque (β = 31.2 +/- 7.9,
P<0.0001), and ankle extension strength (β = 3.8 +/- 0.5,
P<0.0001). It was concluded that the serum magnesium
concentration is an independent correlate of muscle
performance in older persons. Whether magnesium
supplementation improves muscle function remains to be
shown.
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