Mediterranean Diet, Telomere Maintenance and Health Status among Elderly
Telomere Maintenance and Health Status among Elderly. PLoS
ONE 8(4): e62781. doi:10.1371/journal.pone.0062781
Mediterranean Diet, Telomere Maintenance and Health Status among Elderly
Virginia Boccardi 0
Antonietta Esposito 0
Maria Rosaria Rizzo 0
Raffaele Marfella 0
Michelangela Barbieri 0
Giuseppe Paolisso 0
Manlio Vinciguerra, University College London, United Kingdom
0 Department of Internal Medicine, Surgical, Neurological Metabolic Disease and Geriatric Medicine, Second University of Naples , Naples , Italy
Leukocyte telomere length (LTL) and rate of telomere shortening are known biomarkers of aging while, numerous studies showed that Mediterranean diet (MD) may boost longevity. We studied association between telomere length, telomerase activity and different adherence to MD and its effects on healthy status. The study was conducted in 217 elderly subjects stratified according Mediterranean diet score (MDS) in low adherence (MDS#3), medium adherence (MDS 4-5) and high adherence (MDS$6) groups. LTL was measured by quantitative polymerase chain reaction and telomerase activity by a PCRELISA protocol. High adherence group showed longer LTL (p = 0.003) and higher telomerase activity (p = 0.013) compared to others. Linear regression analysis including age, gender, smoking habit and MDS showed that MDS was independently associated with LTL (p = 0.024) and telomerase activity levels (p = 0.006). Telomerase activity was independently associated with LTL (p = 0.007) and negatively modulated by inflammation and oxidative stress. Indeed, telomerase levels were associated with healthy status independently of multiple covariates (p = 0.048). These results support a novel role of MD in promoting health-span suggesting that telomere maintenance, rather than LTL variability is the major determinant of healthy status among elderly.
Telomere length, or more precisely, the rate of telomere
shortening, is a biomarker of biological aging  and eating
nutrient-rich foods might delay aging process and reduces risk of
many chronic diseases . The role of telomere length in cellular
senescence and development of chronic disease associated with
physiological aging has been addressed in several studies [3,4].
Although telomere length may predict clinical outcomes and
mortality among humans, cells with shortened telomeres remain
genetically stable if the telomere maintenance system, which
includes mainly telomerase, is fully functioning . Metabolic
factors, such as abdominal fat and increased circulating glucose
levels are related to shorter telomeres and lower telomerase
activity , supporting the role of lifestyle and environmental
factors on telomeres maintenance. The effect of diets on human
health has already been evaluated in many studies while limited
are evidences on the relative importance of dietary intake on
telomeres maintenance and stability. During the past years
population-based surveys and large-scale clinical trials have
provided scientific evidences that diet, and especially those rich
in fruits, vegetables, fish and low-fat dairy products, are associated
with lower incidence of various chronic diseases and higher
survival [9,10]. Accordingly longer LTL is related to a more
healthy diet, including greater intake of antioxidant [11,12], less
processed meat consumption , intake of fruits and vegetables
and less dietary fat [13,14]. Various nutrients as well as changes in
diet and lifestyle have been already shown to influence telomere
length through mechanisms reflecting their role in cellular
functions including inflammation, oxidative stress, DNA integrity
and DNA methylation .
The Mediterranean diet (MD) is one of the healthiest dietary
pattern in the world due to its relation with low morbidity and
mortality for some chronic diseases [15,16]. This diet has benefits
on risk factors for cardiovascular diseases such as lipoprotein
levels, endothelium vasodilatation, insulin resistance, antioxidant
capacity, incidence of acute myocardial infarction, and global
cardiovascular mortality . Increasing evidences show that
adherence to Mediterranean-diet style correlates to higher
longevity and healthy aging, not only in countries from the
Mediterranean Basin but also in other non-Mediterranean
countries as well [17,18]. A possible link between telomere length
or maintenance and MD has been also recently suggested. A more
recent in vitro study showed that Mediterranean diet protects the
cells from oxidative stress preventing cellular senescence, cellular
apoptosis and reducing telomere attrition . Whether a different
adherence to MD may affect telomeres length and/or PBMC
telomerase activity is still unknown and poorly investigated. Thus,
we aim at investigating the hypothesis that the lower adherence to
MD pattern might be associated with markers of accelerated
cellular aging, including reduced telomerase activity and shortened
telomere length in a cohort of elderly subjects from the South Italy.
Considering that PBMC telomerase activity is associated with
a lower incidence of age-related diseases , we also aim at
investigating the potential association between telomere length,
telomerase activity and Mediterranean diet adherence as well as
their effects on healthy status among elderly subjects.
Materials and Methods
Investigation has been conducted in accordance with the ethical
standards. After a clear explanation of the potential risk of the
study, all subjects provided written informed consent to participate
in the study, which was approved by the Ethical Committee of the
Second University of Naples.
385 Caucasians subjects living in Campania (Southern Italy)
and referred to our Department have been screened. To avoid
bias, individuals with evidence of acute inflammatory or infectious
diseases, diabetes, malignancies, immunologic or hematologic
disorders or treatment with anti-inflammatory drugs were
excluded from the study. In total 217 subjects have been selected.
At enrolment a dietary questionnaires to participants was
administered and a full medical history was collected. Clinical
information was obtained by routine laboratory analyses, history
and physical examination. Data collection included an interview
concerning demographics, health-related behaviors, functional
status and cognitive function. A validated health questionnaire
 was used to determine the presence, history of, or absence of
the following diseases: hypertension, congestive heart failure,
myocardial infarction, peripheral vascular disease, dementia,
cancer, stroke, chronic obstructive pulmonary disease (COPD),
and diabetes. We used the Barthel Activities of Daily Living (ADL)
Index, a validated instrument, to assess physical function (scores
range from 0 to 100) . Healthy old were defined as those
individuals with a Barthel score .90 (independent range) and the
absence of all of the following diseases: hypertension, congestive
heart failure, myocardial infarction, peripheral vascular disease,
dementia, stroke, and COPD. Unhealthy old had Barthel scores
,80 (requiring at least some assistance) and two or more of the
above diseases .
Mediterranean Diet Score
The degree of adherence to the traditional MD was assessed
using the Mediterranean Diet Score (MDS) according to the
method developed by Trichopoulou et al . Intake of each of 9
food groups was dichotomized using sex-specific median values as
cut-offs. A score of 1 was assigned for above the median level of
presumed beneficial foods (vegetables, legumes, fruits, cereal, fish
and ratio of monounsaturated fats to saturated fats) and
consumptions below the median level of presumed detrimental
foods (meat and dairy products). For ethanol, 1 point was assigned
to men who consumed between 10 and 50 g per day and to
women who consumed between 5 and 25 g per day. Thus, the
total MDS ranged from 0 (minimal adherence to the traditional
Mediterranean diet) to 9 (maximal adherence). For analytical
purposes, we categorized the MDS into three groups as follows:
low adherence (MDS#3), medium adherence (MDS 45) and
high adherence (MDS$6) to the diet . Subjects showing
inconstant adherence to diet in the last three months were ruled
Anthropometric determinations (weight, height and body mass
index, BMI) were measured by standard techniques. Blood
samples were collected in the morning after the participants had
been fasting for at least 8 hours. Plasma glucose was determined
immediately by the glucose oxidase method (Glucose
Autoanalyzer, Beckman Coulter, Inc., Fullerton, CA, USA). Plasma fasting
cholesterol and triglycerides were determined by routine
laboratory methods (Roche Diagnostics, GmbH, Mannheim, Germany).
Serum concentrations of IL-6 were determined in duplicate using
a highly sensitive, quantitative sandwich enzyme assay (Quantikine
HS PharmPak, R&D Systems). High-sensitivity TNF-a was
assayed by immunonephelometry on a Behring Nephelometer 2
(Dade Behring, Marburg, Germany). Plasma C-reactive protein
was determined using automated turbidimetry. Nitrotyrosine
plasma concentration, marker of oxidative stress, was assayed by
enzyme linked immunosorbent assay. Nitrotyrosine was
determined because this modified amino acid is a product of
freeradical (O2) interaction with nitric oxide (NO). The interaction of
O2 with NO is very rapid and leads to inactivation of NO and
production of the potent oxidant peroxynitrite. Detection of
nitrotyrosine is strongly suggestive of increased generation of
Telomerase Activity Measurement in PBMC
PBMC were isolated by centrifugation in a Lympho-Ficoll
gradient and preserved at 280uC before analysis. Telomerase
activity in PBMC was measured using a commercial telomerase
PCR-ELISA (Roche Diagnostics Corp., Indianapolis, IN, USA),
based on the telomeric repeat amplification protocol. The assay
procedures followed the recommendations of the manufacturer,
with each sample being analyzed in triplicate.
Mean telomere length was measured quantitatively in genomic
DNA from white blood cells. Genomic DNA was prepared using
a commercial DNA extraction kit following the manufacturers
instructions (Nucleic Acid and Protein
Purification-MachereyNagel). Average TL in peripheral white blood cells was measured
using a validated quantitative polymerase chain reaction (Q-PCR)
method as described by Cawthon  which measures the relative
average TL in genomic DNA by determining the ratio of telomere
repeat copy number to single-copy gene copy number (T/S ratio)
in experimental samples relative to a reference sample. Telomere
primers were tel1b, 59-cggtttgtttgggtttgggtttgggtttgggtttgggtt-39,
final concentration 100 nM; and tel2b,
59-ggcttgccttacccttacccttacccttacccttaccct-39, final concentration 900 nM. Single copy
gene (b-globin) primers were hbg1, 59-gcttctg
acacaactgtgttcactagc-3, final concentration 300 nM; and hbg2,
59-caccaacttcatccacgttcacc-39, final concentration 700 nM. The T signal for an
experimental DNA sample is the number of nanograms of the
reference DNA that matches the experimental sample for copy
number of the telomere repeats. All samples were measured in
triplicate, and the average was used for analyses. The coefficient of
variation was 1.98%. Results obtained using this method correlate
very well with those obtained with the traditional terminal
restriction fragment (TRF) length by Southern blot technique
. To obtain the TL for the reference DNA, we used the T/S
ratios of 30 DNA samples with known mean TRF lengths obtained
by Southern blot technique. The relative T/S ratios and the
means telomere length by the Southern blot approach significantly
correlated (r = 0.667; p = 0.001). The slope of the linear regression
line through a plot of T/S ratio (the x axis) versus mean TRF
length (the y axis) is the number of base pairs of telomeric DNA
corresponding to a single T/S unit. TL was successfully measured
in all 217 individuals.
Calculations and Statistical Analyses
The observed data are normally distributed (Shapiro-Wilk
WTest) and presented as means 6 Standard Deviation (SD).
Oneway ANOVA followed by Bonferroni multiple testing correction
was used to assess differences in clinical and biochemical data
among the presented groups. Pearson correlation coefficients were
calculated to evaluate the relationship between subjects age and
the LTL as indicated.
A cluster analysis allowed us to evaluate whether clustering of
variables of inflammation was associated with LTL variability. For
this purpose, we created a compound score, referred to as
a clustering score. A z score quantifies the original score in terms of
the number of SDs that score is from the mean of the distribution.
It was calculated as the sum of the z scores of the main variable of
inflammation (IL-6, TNF-a and CRP). A z score indicates the
position of an individual value of a variable in the total distribution
of the variable in the population and is calculated as follows:
(individual value - mean value)/SD.
Linear regression analysis was used to test the association of the
different adherence to Mediterranean Diet with LTL and
telomerase activity levels independently of multiple confounding
factors. A binary logistic regression analysis was used to test the
association between telomerase activity levels and healthy status
independently of multiple covariates. Because some of the
predictor variables used in the regression analyses were correlated,
we performed collinearity analysis. Using variance inflation factors
(VIF), no collinearity problems were detected in our data. Sample
size calculation was estimated on an IBM PC computer by
GPOWER software. The resulting total sample size, estimated
according to a global effect size of 25% with type I error of 0.05
and a power of 90% was 207 patients. All p values presented are
2tailed and a p#0.05 was chosen for levels of significance. Statistical
analyses were performed using SPSS 17 software package (SPSS,
Inc., Chicago, IL) or GraphPad Prism software version 5.0 (San
Characteristics of all Study Population
217 unrelated Caucasians subjects (115 (53%) men and 102
(47%) women) were enrolled to the present study. Participants
were old (mean age = 77.962.7 years) and slightly overweight
(Body Mass Index (BMI) = 25.861.4 kg/m2) with a similar
proportion between men and woman. The mean age of participants
was 78.062.9 years for men (range 7186) and 77.762.5 years for
women (range 7187). According to gender ratio women had
significantly lower BMI (25.361.3 kg/m2 vs 26.261.4 kg/m2,
p = 0.001) compared men, while no differences among other
clinical and biochemical characteristics as well as inflammatory
and oxidative stress biomarkers were found (data not shown).
As expected in the all study population a statistically significant
inverse correlation between LTL and age (r = 20.258, p,0.001)
was found. In particular, each 1-y increment in age, LTL
decreases by 0.058 Kb. Independently of age, women had
significantly longer LTL than men (5.06 Kb60.56 Kb and
4.73 Kb60.60 Kb respectively, p,0.001), while no difference in
PBMC telomerase activity levels (0.8860.20 OD vs
0.8860.19 OD) between gender was found.
Stratifying subjects in non smoker, former smoker and current
smoker, a statistically significant difference in LTL variability
between groups was found (4.98 Kb60.61 Kb,
4.92 Kb60.54 Kb and 4.49 Kb60.53 Kb respectively,
p,0.001), while no difference in basal telomerase activity between
groups was found (0.8960.20 OD, 0.8560.21 OD and
0.9160.17 respectively, p = 0.375 ).
A significant positive correlation (r = 0.151; p = 0.028) between
telomere length and PBMC telomerase activity levels was found
even after adjustment for age, gender and smoking habit (Figure 1).
Characteristics of Study Population according to
Mediterranean Diet Score
Table 1 describes the general clinical and biochemical
characteristics of participants according to MDS (Mediterranean
Diet Score) subgroups: low adherence (MDS#3), medium
adherence (MDS 45) and high adherence (MDS$6). 32.3%
showed low adherence (MDS#3) to the Mediterranean diet,
31.3% medium adherence (MDS 45) and 36.4% high adherence
(MDS$6) to this diet. No participants obtained a score of 9, as an
indicator of the maximal adherence to the Mediterranean Diet.
Higher frequency of female, no smokers and healthy subjects in
the high adherence group were found.
Participants with the highest adherence to MD (MDS$6)
showed longer telomere length (p = 0.003) as well as higher
Mediterranean Diet Score
former smoker % (n) 36.2 (21)
current smoker % (n) 52.9 (19)
Data are means 6 standard deviation.
p values were obtained using x2 test* or ANOVA.
telomerase activity (p = 0.013) compared to other groups (Figure 2).
Such a difference resulted significant even after adjustment for age,
gender and smoking habits (p = 0.043 and p = 0.048, respectively).
Every 1-y increment in age, LTL decreases by 0.072 Kb
(b = 20.456, p = 0.001), 0.057 (b = 20.284, p = 0.043) and 0.051
(b = 20.293, p = 0.015) in low adherence, medium and high
adherence groups respectively, showing a statistical different
telomere attrition between MDS groups (p = 0.001) along with
The independent effect of diet on telomere length and PBMC
telomerase activity variability was tested by a linear regression
analysis controlling by multiple covariates. Models including age,
gender, smoking habit and MDS showed that MDS were
independently associated with both LTL variability (b = 0.141
p = 0.024; R2 = 0.209) and telomerase activity levels (Table 2,
Model 1). A model having LTL as dependent variable and age,
gender, smoking habit, MDS and telomerase activity as
independent variables, showed that telomerase activity (b = 0.167
p = 0.007; R2 = 0.226) but not MDS (b = 0.110 p = 0.181) was
independently associated with LTL variability. In this latter model
age, gender and smoking habit were independently associated with
Mediterranean Diet, Inflammation and Telomere
Subjects with the highest adherence score (MDS $6) showed
lower plasmatic levels of CRP (0.4160.31 mg/dl vs
0.5660.46 mg/dl, p = 0.018), IL-6 (2.2760.76 pg/ml vs
2.5560.65 pg/ml, p = 0.010), TNF-a (2.3360.71 pg/ml vs
2.6260.62 pg/ml, p = 0.021) and nitrotyrosine
(0.2360.07 mmol/L vs 0.2660.07 mmol/L, p = 0.009) compared
to low adherence group respectively.
A partial correlation analysis, controlled by age, gender and
smoking habit, showed that LTL negatively correlated with
inflammation score (r = 20.244; p,0.001) as well as with
nitrotyrosine (r = 20.174; p = 0.011). PBMC telomerase activity
levels negatively correlated with both inflammation (r = 20.138;
p = 0.048) and nitrotyrosine levels (r = 20.157; p = 0.022).
Inflammation score, calculated as the sum of the z scores of the main
variable of inflammation, CRP, IL-6 and TNF-a, positively
correlated with nitrotyrosine levels (r = 0.556, p,0.001).
Testing the effect of multiple covariates on telomerase activity
levels, a linear regression analysis controlling by age, gender,
smoking habit, MDS and inflammation score showed that
inflammation but not MDS was independently associated with
telomerase activity variability (Table 2, Model 2).
Mediterranean Diet, Telomere Maintenance System and
Categorizing individuals as healthy old (Barthel score .90
and the absence of all of the following disease: hypertension,
myocardial infarction, vascular diseases, dementia, stroke,
congestive heart failure) and as unhealthy old (Barthel score ,80
and two or more of the above disease), higher frequency of healthy
subjects in the MD highest adherence group was found. Healthy
old (n = 99) showed significantly longer telomere length
(5.01 Kb60.58 Kb vs 4.79 Kb60.61 Kb, p = 0.008) compared
the unhealthy group (n = 118) as well as higher PBMC telomerase
activity (0.9260.19 vs 0.8560.20, p = 0.022). A binary logistic
regression analysis with healthy status as dependent variable and
Figure 2. LTL and Telomerase Activity according Mediterranean Diet Score subgroups. Data are means 6 standard deviation. MDS#3:
n = 70; MDS 45: n = 68; MDS$6: n = 79. p values were obtained using ANOVA followed by Bonferroni multiple testing correction. A) *p = 0.003;
MDS$6 vs MDS#3 p = 0.009 and MDS$6 vs MDS 45 p = 0.011 B) *p = 0.013; MDS$6 vs MDS#3 p = 0.028 and MDS$6 vs MDS 45 p = 0.033. LTL,
Leukocyte Telomere Length; MDS, Mediterranean Diet Score.
age, gender, smoking habit, inflammation, telomerase activity
levels, LTL and MDS as covariates showed that only telomerase
activity was independently associated with a better health status
(Odds ratio = 4.257, 95% CI = 1.01117.926, p = 0.048).
Telomere attrition occurs as the result of cellular replication and
is accelerated by various environmental factors such as
inflammation and oxidative stress . Longer LTL relates to a more
healthy diet  even if, to the best of our knowledge, the relative
effect of specific diet on LTL and telomerase activity in humans is
poorly investigated [12,14]. Mediterranean diet is one of the most
healthy dietary pattern in the world due to its relation with a low
morbidity and mortality for some chronic diseases, potentially
affecting longevity and health-span [15,16]. However, exactly how
the traditional MD may affect life expectancy remains unknown,
although evidences show that the overall dietary pattern and not
any particular food may boost longevity. It is well established that
one important effect of Mediterranean-style diet in prolonging
lifespan is associated with reduced systemic oxidative stress and
inflammation [28,29]. Therefore, we hypothesized that
Mediterranean diet would be associated with the rate of telomere
shortening and telomerase activity in a manner consistent with
reported associations between such diet and inflammation, chronic
diseases, and rate of mortality.
Using data from a population-based study of elderly subjects
from the Mediterranean area of Campania (South Italy), we found
evidence of a retrospective association between high adherence to
Mediterranean diet style and telomere maintenance system. The
major findings of our investigation are: i) higher adherence to MD
significantly correlates with telomere length, independently of
multiple confounding variables affecting telomere attrition ii)
PBMC telomerase activity is significantly and independently
associated with LTL variability iii) MD is independently associated
with LTL variability iiii) telomerase activity is associated with
healthy status independently of multiple confounding factors,
including LTL variability. So far, this is the first study aimed at
investigating the relationship between telomere length, PBMC
telomerase activity and adherence to Mediterranean diet among
elderly people. Our study show that people with the highest
adherence to this diet have longer telomere length and higher
telomerase activity levels in peripheral white blood cells,
independently of multiple confounding variables. We hypothesized
that the high adherence to Mediterranean diet, influencing PBMC
telomerase activity levels, is associated with lower telomere
attrition along with aging. In fact, we found a positive association
between telomere length and adherence to MD, independently of
multiple confounding variables known to affect telomere attrition.
Many factors such as genetic and environmental factors
modulate LTL attrition even if telomeres can remain genetically
stable if the telomere maintenance system, which includes mainly
telomerase, is fully functioning. Numerous evidences show that
various nutrients as well as changes in diet and lifestyle may
influence telomere length  through mechanisms which reflect
their role in many cellular functions including inflammation,
oxidative stress, and potentially PBMC telomerase activity .
Importantly, we found that longer LTL correlates with higher
PBMC telomerase activity, while stratifying subjects according
MDS, participants with higher adherence to MD show longer
telomeres as well as higher PBMC telomerase activity. MDS is
independently associated with both telomere length and
telomerase activity levels, but most importantly the regression model show
that the effect of MD on LTL variability is mediated by telomerase
activity levels independently of multiple confounding factors.
These findings are new and innovative supporting previous data
showing that higher telomerase activity in PBMC in response to
changes in diet and lifestyle [14,30]. Recently, Ornish et al. 
showed that diet can modulate telomerase activity in PMBC while
if such an effect translated into change in the rate of telomeres
shortening is unclear. Interestingly, here, we found that PBMC
telomerase activity is significantly and independently associated
with LTL variability. A potential explanation of such finding is
that the high adherence to Mediterranean diet may stimulate
PBMC telomerase activity, either directly by the effect of some
specific nutrients including in the diet or indirectly by the global
effect of diet on the modulation of inflammation and oxidative
status. Accordingly we found that subjects with higher adherence
to MD, have lower plasmatic level of inflammatory substrate and
oxidative stress, as shown by lower levels of CRP, IL-6, TNF-a and
nytrotirosine. The effect of diet is independent of the main
variables affecting LTL variability. Interestingly, up-regulating
telomerase in vitro promotes cell longevity and genomic stability
 and no study evaluated such an effect in vivo. Telomerase
activity is an important determinant of telomere length and may
be considered a new marker measured in very few studies in
human beings. According to previous studies , we show that
elderly with a better healthy status have longer LTL, and we first
show that the better healthy status is associated with higher PBMC
telomerase activity. We tested the relationship between telomerase
activity and healthy status and we found a significant positive
association independently of multiple confounding factors, which
suggests that telomere stability rather than LTL may be the major
determinant of healthy status.
Thus, it is possible to speculate that the higher telomerase
activity in PBMCs as a result of the quality of adherence to the
MD, might have an important clinical relevance and may
represent a new biomarkers of healthy aging. In recent studies
conducted in mouse model, it has been show that telomerase
activation inducted by gene therapy [32,33] or TA-65 stimulator
, delays physiological aging and extendslifespan. Most
importantly these studies show that the activation of telomerase
is associated to an improvement of certain health-span indicators
including glucose tolerance, osteoporosis and skin fitness, without
much increasing global cancer incidence. Again, in mouse,
telomerase activity is associated to lower LDL cholesterol 
playing an important role in the development of cardiovascular
disease . However, the significance of an increase in
telomerase activity in humans remained to be elucidated. Our
findings in an elderly population reveal a lower incidence of
chronic disease such as hypertension, myocardial infarction,
vascular diseases, dementia, stroke, congestive heart failure among
people with higher circulating telomerase activity levels. For the
first time, we show the effect among humans of Mediterranean
diet on telomerase activity modulation. Our results, showing
a higher frequency of healthy subjects with higher telomerase
activity as well as longer telomeres in the high adherence diet
subgroup, support a novel role of Mediterranean diet in promoting
health-span. It is possible to speculate that the integrity of telomere
maintenance and its related stability than individual LTL, is the
major determinant of healthy status among elderly people.
The limited number of subjects and the lack of a replication
study are potential limitations of this study. Another limitation is
the method used to estimate mean telomere length, the qPCR
assay. The assay has been reported to show a strong correlation
with mean telomere length measured by the Southern blot . In
our study the correlation is slightly weaker. This finding could be
explained by the small sample size and also because the Southern
blot measures a variable amount of non-telomeric DNA, hence the
correlation is not expected to be perfect. However, in our
population study, we found a decrease in LTL with increasing
aging as well as shorter LTL in men, which both represent a very
good quality control. The quantitative fluorescence in situ
hybridisation (qFISH) protocol , using specific acid probes to
hybridize to the telomeric repeats would be more accurate
compared with the used approach, thus, further studies will be
necessary to replicate and validate our findings.
In conclusion our results give an evidence for an association
between high adherence to the MD and a slower rate of cellular
ageing. Taken together all these data support the novel hypothesis
that a lower rate of telomere shortening and higher PBMC
telomerase activity might be involved in lifespan and most
importantly in health-span among populations consuming
traditional Mediterranean diet.
Conceived and designed the experiments: VB GP MB MRR RM.
Performed the experiments: AE VB. Analyzed the data: VB MB RM MRR
GP AE. Contributed reagents/materials/analysis tools: VB AE. Wrote the
paper: VB MB GP.
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