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Leptin reduction after endurance races differing in duration and energy expenditure

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Marco Zaccaria at University of Padova
Marco Zaccaria
Andrea Ermolao at University of Padova
Andrea Ermolao
Giulio Sergio Roi at University of Bologna
Giulio Sergio Roi
Piera Englaro
Piera Englaro
Piera Englaro
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Abstract and Figures

Serum leptin concentrations are reduced in the presence of a negative energy balance. It has been demonstrated, however, that strenuous and prolonged exercise, which induces a marked negative energy balance, is not always followed by a reduction in serum leptin levels. We therefore analysed serum leptin concentrations before and after three endurance races, which differed in duration and energy expenditure (EE), with the aim of clarifying the relationship between the level of EE and the reduction in leptin levels. Forty-five males participated in one of three competitive endurance races, a half-marathon run [21.097 km, estimated EE 1,400 kcal (5,852 kJ)], a ski-alpinism race [about 45 km, estimated EE 5,000 kcal (20,900 kJ)], and an ultramarathon race [100 km, estimated EE 7,000 kcal (29,269 kJ)]. Blood samples for analysis of serum leptin, and plasma free fatty acids (FFA) were collected before and after the races. Pre-race leptin values were significantly correlated with both body mass index and body fat mass ( r=0.672 and r=0.699, respectively; P<0.0001). After exercise, serum leptin levels decreased significantly in the ultramarathon [from 4.15 (0.63) microg/l to 1.01 (0.15) microg/l; P<0.001] and in the ski-alpinism race [from 1.10 (0.28) microg/l to 0.62 (0.15) microg/l; P<0.01], but not in the half-marathon [from 1.38 (0.40) microg/l to 1.20 (0.36) microg/l]. Plasma FFA were found to have significantly increased in all three of the races, showing a negative correlation with the percent reduction in leptin ( r=0.369, P<0.02). Our data indicate that only a prolonged endurance exercise involving a high EE can induce a marked reduction in circulating serum leptin levels.
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ORIGINAL ARTICLE
Marco Zaccaria Æ Andrea Ermolao Æ Giulio Sergio Roi
Piera Englaro Æ Giovanna Tegon Æ Maurizio Varnier
Leptin reduction after endurance races differing in duration
and energy expenditure
Accepted: 7 February 2002 / Published online: 26 April 2002
Ó Springer-Verlag 2002
Abstract Serum leptin concentrations are reduced in the
presence of a negative energy balance. It has been
demonstrated, however, that strenuous and prolonged
exercise, which induces a marked negative energy bal-
ance, is not always followed by a reduction in serum
leptin levels. We therefore analysed serum leptin con-
centrations before and after three endurance races,
which differed in duration and energy expenditure (EE),
with the aim of clarifying the relationship between the
level of EE and the reduction in leptin levels. Forty-five
males participated in one of three competitive endurance
races, a half-marathon run [21.097 km, estimated EE
1,400 kcal (5,852 kJ)], a ski-alpinism race [about 45 km,
estimated EE 5,000 kcal (20,900 kJ)], and an ultramar-
athon race [100 km, estimated EE 7,000 kcal
(29,269 kJ)]. Blood samples for analysis of serum leptin,
and plasma free fatty acids (FFA) were collected before
and after the races. Pre-race leptin values were signifi-
cantly correlated with both body mass index and body
fat mass (r=0.672 and r=0.699, respectively;
P<0.0001). After exercise, serum leptin levels decreased
significantly in the ultramarathon [from 4.15 (0.63) lg/l
to 1.01 (0.15) lg/l; P<0.001] and in the ski-alpinism
race [from 1.10 (0.28) lg/l to 0.62 (0.15) lg/l; P<0.01],
but not in the half-marathon [from 1.38 (0.40) lg/l to
1.20 (0.36) lg/l]. Plasma FFA were found to have sig-
nificantly increased in all three of the races, showing a
negative correlation with the percent reduction in leptin
(r=0.369, P<0.02). Our data indicate that only a pro-
longed endurance exercise involving a high EE can in-
duce a marked reduction in circulating serum leptin
levels.
Keywords Endurance exercise Æ Leptin Æ Energy
expenditure Æ Free fatty acids
Introduction
Leptin, a protein that is expressed and secreted by adi-
pose tissue, regulates food intake by acting as a hypo-
thalamic signal of satiety. Under steady-state conditions
of energy balance, leptin is considered a good index of
the amount of adipose stores, while under non-steady-
state conditions, leptin is no longer a reliable marker of
body fat stores. In fact, a negative energy balance state,
such as during prolonged fasting, decreases leptin con-
centrations, whereas a positive energy balance, such as
during overfeeding, increases leptin levels (Kolaczynski
et al. 1996).
Exercise is a physiological condition that effects a
rapid increase of energy expenditure that is positively
related to the intensity and duration of the exercise itself.
Thus, a strenuous and prolonged exercise bout that in-
duces a marked negative energy balance state would be
expected to decrease leptin levels. However, reports on
the effects of prolonged exercises on serum leptin con-
centrations have yielded contradictory findings. Serum
leptin has been reported to be reduced or unchanged
both after exercises performed in the laboratory, and
after strenuous endurance races, such as marathons or
ultramarathons (Hickey et al. 1996; Koistinen et al.
1998; Landt et al. 1997; Tuominen et al. 1997). These
contradictory results may be due to differences in the
experimental procedures used in the different studies
(exercise protocols, diet before and during the exercise,
circadian rhythm of leptin). We therefore analysed se-
rum leptin concentrations before and after three com-
petition endurance races that differed in duration and
Eur J Appl Physiol (2002) 87: 108–111
DOI 10.1007/s00421-002-0606-4
M. Zaccaria (&) Æ A. Ermolao Æ P. Englaro Æ G. Tegon
M. Varnier
U.O.A. di Medicina dello Sport,
Dipartimento di Scienze Mediche e Chirurgiche,
Universita
`
di Padova,
Via Ospedale Civile, 105, 35128 Padova, Italy
E-mail: marco.zaccaria@unipd.it
Tel.: +39-49-8215650
Fax: +39-49-8215810
G.S. Roi
Casa di cura ‘‘S. Maria’’,
Viale Piemonte, 70 Castellanza, Varese, Italy
energy expenditure, with the aim of verifying the rela-
tionship between the level of energy expenditure and the
reduction in serum levels of leptin.
Methods
Forty-five Caucasian males, all runners usually engaged in com-
petitive races, voluntarily agreed to be included in the study and
gave their written informed consent to participate. Each subject
participated in one of three endurance competitive races. The en-
ergy expenditure for each race was estimated following methods
described elsewhere (di Prampero 1986).
The first race was a sea-level, flat half-marathon run
(21.097 km), starting at 9.00 a.m., with a mean exercise time of 1 h
31 min and an estimated mean energy expenditure of 1,400 kcal
(5.852 kJ).
The second race was a 45-km ski-alpinism race, alternating up-
and-downhill running and cross-country skiing. Athletes started at
8.00 a.m. from 2,080 m, reached a maximum altitude of 4,226 m,
and then went down to the finish at 1,637 m. The mean time of the
race was 7 h 21 min, and the mean estimated energy expenditure
was 5,000 kcal (20,900 kJ).
The third race was a 100-km ultramarathon race starting at
3.00 p.m., with a mean time of 15 h 27 min, and a mean estimated
energy expenditure of 7.00 kcal (29,269 kJ).
All subjects were in a post-absorptive condition, having eaten a
carbohydrate-rich meal about 2 h before the start of the race.
During the race they drank water, and energy drinks (sweet tea,
isotonic drinks), and ate energy bars ad libitum.
Before each race, in all subjects the body mass index (BMI) and
body composition were assessed by bioelectrical impedance (BIA
101 RJL/Akern, Florence, Italy). Blood samples for measurement
of serum leptin and plasma free fatty acids (FFA) were collected
immediately before and within 20 min after the race, except in the
ski-alpinism race, in which blood samples were collected from
subjects in a post-absorptive condition the day before the race, at
about the same time of day as the beginning of the race.
Serum leptin was measured using a specific double-antibody
radioimmunoassay method (Sensitivity 0.03lg/l; inter- and intra-
assay coefficient of variability lower than 7.6% and 5%, respec-
tively). Plasma FFA was determined by an enzymatic method
(NEFA Quick ‘‘BMY’’, Boehringer Mannheim Yamanouchi,
Tokyo, Japan).
Statistical analysis
Data are expressed as mean (SEM). The statistical analysis of pre-
and post-exercise values was made using the Wilcoxon test for
paired data. Pearson’s correlation coefficient was used to test the
relationship between leptin and the fat mass percentage and
between the percentage of variation of leptin and FFA. The level of
statistical significance was set at P<0.05.
Results
The characteristics of the subjects under basal condi-
tions are reported in Table 1: ski-alpinism subjects were
the youngest, while the ultramarathon subjects were the
oldest and had the highest BMI, body fat mass and
resting leptin concentrations. The overall pre-race leptin
values of subjects, were significantly correlated with
BMI and with body fat mass (r=0.672 and r=0.699,
respectively; P<0.0001).
After exercise, serum leptin levels significantly de-
creased in subjects who participated in the two ult-
raendurance races [ultramarathon: from 4.15 (0.63) lg/l
to 1.01 (0.15) lg/l, P<0.0005; ski-alpinism race: from
1.10 (0.28) lg/l to 0.62 (0.15) lg/l, P<0.01], while in the
half-marathon, no significant reduction was found [from
1.38 (0.40) lg/l to 1.20 (0.36) lg/l; P=0.065, Fig. 1].
The mean percent decrease in leptin was –71 (3)% in the
ultramarathon, –40 (7)% in the ski-alpinism, and –2.5
(10)% in the half-marathon.
Plasma FFA levels significantly increased at the end
of the races, with the absolute highest level being ob-
served in the longest race [ultramarathon: from 471.3
(92.4) lmol/l to 1,801.4 (188.6) lmol/l, P<0.001; ski-
alpinism: from 486.9 (55.0) lmol/l to 1,484.0
(221.9) lmol/l, P<0.001; half-marathon: from 733.8
(44.1) lmol/l to 1,234.8 (97.5) lmol/l, P<0.001]. The
percent variation in FFA showed a significant inverse
relationship with the percent variation in leptin
(r=0.369, P<0.02).
Discussion
The aim of our study was to investigate the effect on
serum leptin concentration of three endurance races of
different duration and energy expenditure. Two of the
races, the ski-alpinism race and the ultramarathon, were
very prolonged, medium- to high-intensity endurance
races (7 h 15 min and 15 h 27 min, respectively),
Table 1. Characteristics of
races and subjects. Please note
that energy expenditure is given
in kcal, where 1 kcal=4.19 kJ.
(BMI Body mass index)
Parameter Half-marathon Ski-alpinism Ultramarathon
Distance (km) 21.097 45 100
Mean [range] duration
(h:min)
1:30 (1:08–1:50) 7:21 min (5:16–8:08) 15:27 min (13:00–17:00)
Energy expenditure
(estimated kcal)
1,400 5,000 7,000
Number of subjects 23 11 11
Age (years) 44.3 (2.7) 34.6 (2.5)* 46.1 (3.2)
BMI (kg/m
2
) 23.2 (0.4) 22.0 (0.4) 26.4 (0.9)**
,
***
Body fat mass (%) 14.5 (0.7) 12.8 (0.9) 17.7 (0.8)**
,
***
*P<0.05 vs ultramarathon and half-marathon;
**P<0.05 vs half-marathon;
***P<0.05 vs ski-alpinism
109
involving a very high energy expenditure (5,000 kcal and
7,000 kcal, respectively). The third race, the half-mara-
thon, was a shorter, high-intensity race (1 h 31 min)
involving a lower energy expenditure (1,400 kcal). Se-
rum leptin concentration decreased significantly in the
ultramarathon (–71%) and in the ski-alpinism race
(–40%), but not in the half-marathon (–2.5%). Thus, the
major finding of our study was that only prolonged
strenuous endurance exercises involving elevated energy
expenditure reduced serum leptin concentrations.
Previous reports on the effect of exercise on serum
leptin concentrations are contradictory: acute exercise
lasting 30 min, performed at different intensities and
caloric expenditure (Weltman et al. 2000), and a 20-mile
(32.2 km) treadmill run (Hickey et al. 1996) did not af-
fect serum leptin concentrations, while a 3-h cycle erg-
ometer exercise bout induced a 42% decrease in serum
leptin (Koistinen et al. 1998). Studies on marathon
runners, on the other hand, showed either no changes
(Koistinen et al. 1998) or a slight (11%), but significant
reduction (Tuominen et al. 1997) in leptin levels. In the
only report available on ultraendurance exercise
[101 miles (162.5 km) at a medium altitude], a significant
reduction (32%) in leptin levels was found (Landt et al.
1997). These contradictory or non-homogeneous find-
ings on the leptin response to different kinds of exercise
could be explained, at least partially, by differences in
the experimental procedures (i.e. exercise protocols, diet
before and during the exercise, circadian rhythm of
leptin).
Fasting causes a fall in circulating leptin levels, be-
ginning after 12 h (Kolaczynski et al. 1996). Since most
of the available studies on the effect of exercise on leptin
levels were performed in overnight-fasted subjects, the
effect of fasting could have influenced basal leptin levels
and, consequently, their response to exercise (Hickey
et al. 1996; Landt et al. 1997). To avoid any interference
from fasting, our subjects were studied in a post-ab-
sorptive condition, having eaten a carbohydrate-rich
meal about 2 h before the start of the race. This eating
pattern, which is usual for people participating in
endurance races, could have counteracted the fasting-
induced fall in leptin; in fact, it has been shown that
small amounts of glucose prevents the reduction in se-
rum leptin that usually occurs during prolonged fasting
(Kolaczynski et al. 1996). However, if a small amount of
glucose has been reported to be sufficient to prevent the
fall in leptin induced by fasting, this does not appear to
happen during prolonged exercise, because we found a
marked decrease in leptin concentrations in spite of the
consumption of energy drinks and energy bars ad libi-
tum during the races. So, from our data, it seems that
the effect of the negative energy balance induced by
exercise prevails over the effect of glucose on leptin
levels.
Variations in the circadian rhythm of leptin may also
influence leptin responses to exercise, since it has been
demonstrated that the highest concentrations of leptin
levels occur between midnight and early morning, fol-
lowed by a progressive decrease, with the lowest con-
centrations occurring at noon and in the early-afternoon
(Licinio et al. 1997). Our findings allow us to rule out
any influence of the circadian rhythm on the two ult-
raendurance races, because pre- and post-exercise ski-
alpinism race samples were collected at the same time
(3.00 p.m.) on two consecutive days, and the post-exer-
cise samples for the ultramarathon were obtained in the
early morning (6.00 a.m.), when leptin is declining but is
still at higher levels than at the time of the start of the
race (3.00 p.m.).
In agreement with other authors (Landt et al. 1997),
we found that FFA were affected markedly by pro-
longed exercise, the mean percentage increase ranging
from 50% to 500%, and showing a significant inverse
relationship with the percent variation of serum leptin.
On the other hand, in the half-marathon we found a
significant increase of FFA not related to leptin varia-
tions, showing that in man, acute variations of FFA
concentrations do not change leptin levels. Thus, the
observed inverse relationship of leptin versus FFA
during exercise seems not consequent to a cause-and-
effect relationship.
In conclusion, our findings indicate that a significant
reduction of serum leptin concentration can be observed
Fig. 1. Mean (SEM) leptin and
free fatty acid (FFA) levels
before (white bars) and after
(shaded bars) the three endur-
ance races.*P<0.01;
**P<0.001
110
only when endurance exercise is very prolonged, with an
energy expenditure by far higher than the energy ex-
pended in 24 h of normal activity. However, the physi-
ological mechanisms regulating the reduction in leptin
that occurs during exercise remain unclear, and are de-
serving of further investigation.
Acknowledgement The authors acknowledge the Federation of
Sport at Altitude for its kind cooperation.
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... Experienced runners, athletes, trained and well-trained were evaluated in 22 studies (Niess et al., 1999;Fehrenbach et al., 2000;Ostrowski et al., 2000;Suzuki et al., 2000Suzuki et al., , 2003Toft et al., 2000;Bonsignore et al., 2002;Zaccaria et al., 2002;Nieman et al., 2003Nieman et al., , 2005Nieman et al., , 2006Nieman et al., , 2007Cox et al., 2010;Abbasi et al., 2013;Chiu et al., 2013;Roupas et al., 2013;Santos et al., 2013b;Shanely et al., 2014;Bachi et al., 2015;Sansoni et al., 2017;Passos et al., 2019;Gaggini et al., 2021). Amateur, recreational runners were present in 13 studies (Drenth et al., 1995;Castell et al., 1996;Starkie et al., 2001;Bonsignore et al., 2002;Kim et al., 2007;Díaz-Castro et al., 2012;Vaisberg et al., 2012Vaisberg et al., , 2013Reihmane et al., 2013;Vuolteenaho et al., 2014;Luna Junior et al., 2016;dos Santos et al., 2020;Sliwicka et al., 2021). ...
... Mean running conclusion times were reported in 68% of the studies. In the half-marathon, the mean times varied between 1:30 and 2:12 h (Zaccaria et al., 2002;Ng et al., 2008;Cox et al., 2010;Abbasi et al., 2013;Reihmane et al., 2013;Niemelä et al., 2016;Costello et al., 2020;Gaggini et al., 2021). In marathons the mean times varied between 2:52 and 4:41 h (Castell et al., 1996;Toft et al., 2000;Pistilli et al., 2002;Henson et al., 2004;Howatson et al., 2010;Scherr et al., 2011Scherr et al., , 2012Nickel et al., 2012;Bernecker et al., 2013;Reihmane et al., 2013;Santos et al., 2013a,b;Vaisberg et al., 2013;Shanely et al., 2014;Vuolteenaho et al., 2014;Wilhelm et al., 2014;Niemelä et al., 2016;Clifford et al., 2017;Passos et al., 2019;Pugh et al., 2019;Sierra et al., 2019a;Batatinha et al., 2020;dos Santos et al., 2020;Larsen et al., 2020;Sliwicka et al., 2021;Tavares-Silva et al., 2021). ...
... In marathons the mean times varied between 2:52 and 4:41 h (Castell et al., 1996;Toft et al., 2000;Pistilli et al., 2002;Henson et al., 2004;Howatson et al., 2010;Scherr et al., 2011Scherr et al., , 2012Nickel et al., 2012;Bernecker et al., 2013;Reihmane et al., 2013;Santos et al., 2013a,b;Vaisberg et al., 2013;Shanely et al., 2014;Vuolteenaho et al., 2014;Wilhelm et al., 2014;Niemelä et al., 2016;Clifford et al., 2017;Passos et al., 2019;Pugh et al., 2019;Sierra et al., 2019a;Batatinha et al., 2020;dos Santos et al., 2020;Larsen et al., 2020;Sliwicka et al., 2021;Tavares-Silva et al., 2021). In ultra-marathons, the mean times ranged between 6:00 and 62:20 h (Drenth et al., 1995;Peters et al., 2001;Nieman et al., 2002Nieman et al., , 2003Nieman et al., , 2005Nieman et al., , 2006Nieman et al., , 2007Zaccaria et al., 2002;Mastaloudis et al., 2004;Kim et al., 2007;Donnikov et al., 2009;Chiu et al., 2013;Shin and Lee, 2013;Gill et al., 2015a;Czajkowska et al., 2020;Wołyniec et al., 2020;Benedetti et al., 2021;Skinner et al., 2021), with distances of 51-308 km. Three studies evaluated the specific distances of 35, 35.2 and 40 km, with the following mean conclusion times 5:08 (Yargic et al., 2019), 6:10 (Miles et al., 2006) and 6:50 hours (Skinner et al., 2021) respectively. ...
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... Neuropeptide Y (NPY), a common peptide neurotransmitter, is inhibited by leptin, accordingly regulating food consumption patterns. Leptin and anxiety may be related, even though the NPY-Y1 receptor and the food-regulatory receptor appear to function in quite distinct ways [82,[105][106][107][108][109][110]. ...
... If the cell proves incapable of rectifying the damage and restoring its functionality or if both exogenous and endogenous antioxidant defenses fail to counteract the ROS-induced harm, the cell may be fundamentally and irreversibly damaged [1,116] (Figure 3). receptor and the food-regulatory receptor appear to function in quite distinct ways [82,[105][106][107][108][109][110]. ...
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Full-text available
  • Dec 2022
Background: The Montane ® Yukon Arctic Ultra (YAU) is one of the longest (690 km) and coldest (+10.6°C–43.9°C) ultramarathons worldwide. Taking part in an ultramarathon is associated with great physiological and psychological stress, which can affect one’s mood, level of hormones, and peptides. The current study aimed to identify relationships between peptides, hormones, and mood states in participants during this ultramarathon. Methods: The study cohort consisted of 36 participants (19 men, 17 women, 38.64 ± 9.12 years) split into a finisher ( n = 10), non-finisher ( n = 19), and control group ( n = 7). Data were collected at four time points: baseline (PRE), during (D1 after 277 km, D2 after 383 km), and after the race (POST). Questionnaires were used to assess ratings of perceived exertion (RPE), total quality of recovery (TQR), and profile of mood states (POMS-SF). Serum NPY, leptin, adiponectin, and cortisol were measured. Results: Among non-finishers, scores for confusion, anger, depression, and tension-anxiety (PRE vs. D2, p < 0.05) increased, while vigor decreased (PRE vs. D1, p < 0.05). In contrast, finishers’ tension-anxiety scores decreased (PRE vs. D1, p < 0.05). Fatigue increased in finishers (PRE vs. POST, p < 0.05) and non-finishers (PRE vs. D1, p < 0.05). In non-finishers, depressive mood correlated positively with leptin, anger, and confusion at several time points ( p < 0.001). In finishers, NPY correlated with TQR at PRE ( p < 0.05), while leptin correlated negatively with TQR at POST ( p < 0.05). Tension-anxiety correlated highly with perceived exertion in non-finishers ( p < 0.001) and with cortisol in finishers ( p < 0.05) and non-finishers ( p < 0.001). In finishers, confusion correlated negatively with NPY ( p < 0.01). Conclusion: The study reveals an essential interplay between hormones and mood states affecting performance: Leptin was associated with anger and a depressive mood state in non-finishers and worse recovery in finishers. In contrast, NPY appeared linked to a lower confusion score and heightened recovery in finishers. A simultaneous increase in depressed mood, anger, tension-anxiety, and confusion might harm performance and lead to race failure.
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... A similar direction of change was observed by Zaccaria et al. [61] after an ultramarathon in trained runners (energy expenditure of 7000 kcal) with no change in the half marathon (expenditure of 1400 kcal), as well as by Leal-Cerro [62] in long-distance runners after a marathon (energy expenditure of approximately 2800 kcal). In Zaccari [61], leptin concentration correlated highly negatively with post-exercise FFA concentration and with body weight and resting fat content. ...
... A similar direction of change was observed by Zaccaria et al. [61] after an ultramarathon in trained runners (energy expenditure of 7000 kcal) with no change in the half marathon (expenditure of 1400 kcal), as well as by Leal-Cerro [62] in long-distance runners after a marathon (energy expenditure of approximately 2800 kcal). In Zaccari [61], leptin concentration correlated highly negatively with post-exercise FFA concentration and with body weight and resting fat content. ...
Influence of Training and Single Exercise on Leptin Level and Metabolism in Obese Overweight and Normal-Weight Women of Different Age
Article
Full-text available
Leptin is one of the important hormones secreted by adipose tissue. It participates in the regulation of energy processes in the body through central and peripheral mechanisms. The aim of this study was to analyse the anthropological and physical performance changes during 9 month training in women of different age and body mass. The additional aim was the analysis of leptin levels in the fasting stage and after a control exercise. Obese (O), overweight (OW), and normal-weight (N) women participated in the study. Additional subgroups of premenopausal (PRE) (
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... A study on the prevalence and clinical features ... [2] Occupational exposure and sensitization to ... [3] Close encounters of the microbial ... [4] Recent consensus on the classification of rhinosinusitis ... [5] Diseases of the sinuses: A comprehensive textbook of ... [6] Descriptions of medical ... [7] Scott-Brown's otorhinolaryngology and head ... [8] The role of fungi in diseases of the nose ... [9] Imaging features of invasive and noninvasive fungal ... [10] Controversies surrounding the categorization ... [15] Fungal rhinosinusitis: A retrospective microbiologic ... [16] Invasive and non-invasive fungal rhinosinusitis-a ... [17] Fungal infections of the nose and paranasal ... [18] Endoscopic surgery for mycotic and chronic ... [19] Fungal sinusitis in the immunocompetent ... [20] Incidence and presentation of fungal sinusitis ... [21] A study on the frequency of fungal rhinosinusitis and ... [22] Aerobic bacteria and fungal isolates in maxillary ... [23] Fungal rhinosinusitis: Microbiological and ... [24] Prevalence of noninvasive fungal sinusitis in South ... [25] Allergic fungal rhino-sinusitis frequency in chronic ... [26] ...
... Circulating leptin has been investigated, in man, after the different protocols of exercise that include shortand long-term exercise training [11] and following single sets of exercise (maximal, sub-maximal, short duration, and long duration) [12,13] . There are many conflicting results in the leptin response to exercise [5,[13][14][15] , but it appears that circulating leptin levels are only decreased by sets of the exercise with considerably high intensity [16] and long duration [6,[17][18][19][20] . Data from previous research suggest that altered plasma leptin concentrations are changed for energy intake and expenditure balance, as circulating leptin is influenced by exercise session which meets an energy expenditure threshold. ...
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... Furthermore, some investigators have reported that postexercise cortisol release may affect leptin concentrations. However, Zaccaria et al. [294] compared the effects of three different competitive endurance modalities in 45 trained men. In this sense, the reduction in leptin levels was only observed in the alpine ski and ultramarathon modalities, which had an approximate energy expenditure of 5000 and 7000 kcal, respectively. ...
The Role of Adipokines in Health and Disease
Article
Full-text available
  • Apr 2023
Adipokines are cell-signaling proteins secreted by adipose tissue that has been related to a low-grade state of inflammation and different pathologies. The present review aims to analyze the role of adipokines in health and disease in order to understand the important functions and effects of these cytokines. For this aim, the present review delves into the type of adipocytes and the cytokines produced, as well as their functions; the relations of adipokines in inflammation and different diseases such as cardiovascular, atherosclerosis, mental diseases, metabolic disorders, cancer, and eating behaviors; and finally, the role of microbiota, nutrition, and physical activity in adipokines is discussed. This information would allow for a better understanding of these important cytokines and their effects on body organisms.
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... 60 dakikanın üzerinde yapılan ve uzun süreli egzersiz olarak isimlendirilen bir başka süreç ise, serum leptin düzeyinde azalmaya sebebiyet vermiştir (51,(52)(53). Bu azalma serbest yağ asitlerinin artmasına sebebiyet vermekle birlikte (51,52,54,55,56), glikoz (37,46,52,57) ve insülin değerlerini azalttığı (37,52,57) veya değiştirmediği birçok araştırmacı tarafından ortaya konulmuştur. ...
Leptin ve Egzersiz
Chapter
Full-text available
  • Dec 2021
GIRIŞ Yirmi birinci yüzyılın önemli sağlık problemlerinden biri olan ve son yıllarda dün-yanın her yerinde insan sağlığını önemli düzeyde tehdit eden obezite, toplum sağ-lığı açısından olumsuz yükselişine devam etmektedir. Obezite terminolojik olarak birçok farklı bakış açısına göre tanımlanmış olsa da, kısaca vücutta anormal yağ birikmesi şeklinde ortaya çıkan aşırı kilo alma veya şişman olma şeklinde ifade etmek mümkündür. Obezite sonuçları itibari ile sadece bireyin yaşam kalitesini olumsuz etkilemek-le kalmaz aynı zamanda dünya toplumlarının sağlık harcamalarına daha fazla kaynak aramaya mahkûm eder. Ayrıca obezite ile birlikte ortaya çıkan hastalık-lar ve bu hastalıklara yakalanan insanların bir sonraki insan nesline aktaracakları sağlıksız genetik mirasının da, sağlıksız bir neslin oluşmasına sebep olacağı göz ardı edilmemelidir. Obezitenin yaygınlığı ve riski artarken Dünya Sağlık Örgütü (DSÖ) başta olmak üzere, durumun ciddiyetinin farkında olan toplumlar obezite ile mücadele etme konusunda önemli kaynaklar aramaktadırlar. Bu mücadele çalışmaları arasında önemli olduğunu düşündüğümüz ve özellikle DSÖ'nün ısrarla üzerinde durduğu bireylerin inaktif yaşamdan uzak, aktif bir yaşam tarzı benimsemeleri yönündedir. Dolayısıyla egzersiz ve spor bilimcilere göre aktif yaşam tarzının önemli olduğunu ve bireylerin ancak egzersiz ile birlikte obezite karanlığından aydınlığa doğru çıka-bileceğini, ayrıca kaybedilen sağlıklı beden mirasını yeniden kazanabileceğimizi vurgulamaktadır. Bu noktada insanoğlunun sağlığı konusunda endişe duyan bilim insanları obezitenin önce nasıl engelleneceği ve daha sonra tamamen nasıl orta-dan kaldırılacağı konusunda birçok çalışma yapmaktadırlar.
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Exploring exercise-driven exerkines: unraveling the regulation of metabolism and inflammation
Article
  • Apr 2024
Exercise has many beneficial effects that provide health and metabolic benefits. Signaling molecules are released from organs and tissues in response to exercise stimuli and are widely termed exerkines, which exert influence on a multitude of intricate multi-tissue processes, such as muscle, adipose tissue, pancreas, liver, cardiovascular tissue, kidney, and bone. For the metabolic effect, exerkines regulate the metabolic homeostasis of organisms by increasing glucose uptake and improving fat synthesis. For the anti-inflammatory effect, exerkines positively influence various chronic inflammation-related diseases, such as type 2 diabetes and atherosclerosis. This review highlights the prospective contribution of exerkines in regulating metabolism, augmenting the anti-inflammatory effects, and providing additional advantages associated with exercise. Moreover, a comprehensive overview and analysis of recent advancements are provided in this review, in addition to predicting future applications used as a potential biomarker or therapeutic target to benefit patients with chronic diseases.
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Human leptin levels are pulsatile and inversely related to pituitary - Adrenal function
Article
Full-text available
  • Jun 1997
Leptin communicates nutritional status to regulatory centers in the brain. Because peripheral leptin influences the activity of the highly pulsatile adrenal and gonadal axes, we sought to determine whether leptin levels in the blood are pulsatile. We measured circulating leptin levels every 7 minutes for 24 hours, in six healthy men, and found that total circulating leptin levels exhibited a pattern indicative of pulsatile release, with 32.0 +/- 1.5 pulses every 24 hours and a pulse duration of 32.8 +/- 1.6 minutes. We also show an inverse relation between rapid fluctuations in plasma levels of leptin and those of adrenocorticotropic hormone (ACTH) and cortisol that could not be accounted for on the basis of glucocorticoid suppression of leptin. As leptin levels are pulsatile, we propose that a key function of the CNS is regulated by a peripheral pulsatile signal. In a separate pilot study we compared leptin pulsatility in 414 plasma samples collected every 7 minutes for 24 hours from one obese woman and one normal-weight woman. We found that high leptin levels in the obese subject were due solely to increased leptin pulse height; all concentration-independent pulsatility parameters were almost identical in the two women. Leptin pulsatility therefore can be preserved in the obese.
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Responses of Leptin to Short-Term Fasting and Refeeding in Humans: A Link With Ketogenesis but Not Ketones Themselves
Article
  • Nov 1996
  • DIABETES
We investigated the response of leptin to short-term fasting and refeeding in humans. A mild decline in subcutaneous adipocyte ob gene mRNA and a marked fall in serum leptin were observed after 36 and 60 h of fasting. The dynamics of the leptin decline and rise were further substantiated in a 6-day study consisting of a 36-h baseline period, followed by 36-h fast, and a subsequent refeeding with normal diet. Leptin began a steady decline from the baseline values after 12 h of fasting, reaching a nadir at 36 h. The subsequent restoration of normal food intake was associated with a prompt leptin rise and a return to baseline values 24 h later. When responses of leptin to fasting and refeeding were compared with that of glucose, insulin, fatty acids, and ketones, a reverse relationship between leptin and β-OH-butyrate was found. Consequently, we tested whether the reciprocal responses represented a causal relationship between leptin and β-OH-butyrate. Small amounts of infused glucose equal to the estimated contribution of gluconeogenesis, which was sufficient to prevent rise in ketogenesis, also prevented a fall in leptin. The infusion of β-OH-butyrate to produce hyperketonemia of the same magnitude as after a 36-h fast had no effect on leptin. The study indicates that one of the adaptive physiological responses to fasting is a fall in serum leptin. Although the mediator that brings about this effect remains unknown, it appears to be neither insulin nor ketones.
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Human leptin levels are pulsatile and inversely related to pituitary–ardenal function
Article
  • May 1997
Leptin communicates nutritional status to regulatory centers in the brain1,2. Because peripheral leptin influences the activity of the highly pulsatile adrenal and gonadal axes3,4, we sought to determine whether leptin levels in the blood are pulsatile. We measured circulating leptin levels every 7 minutes for 24 hours, in six healthy men, and found that total circulating leptin levels exhibited a pattern indicative of pulsatile release, with 32.0 1.5 pulses every 24 hours and a pulse duration of 32.8 1.6 minutes. We also show an inverse relation between rapid fluctuations in plasma levels of leptin and those of adrenocorticotropic hormone (ACTH) and cortisol that could not be accounted for on the basis of glucocorticoid suppression of leptin. As leptin levels are pulsatile, we propose that a key function of the CNS is regulated by a peripheral pulsatile signal. In a separate pilot study we compared leptin pulsatility in 414 plasma samples collected every 7 minutes for 24 hours from one obese woman and one normal-weight woman. We found that high leptin levels in the obese subject were due solely to increased leptin pulse height; all concentration-independent pulsatility parameters were almost identical in the two women. Leptin pulsatility therefore can be preserved in the obese.
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The Energy Cost of Human Locomotion on Land and in Water*
Article
  • May 1986
The energy cost of the forms of locomotion discussed throughout this article is summarized in Table 9. This table, as well as the preceding sections of this article, are designed to provide a rather comprehensive and simple set of information for potential readers: medical doctors, who should be able to prescribe to their patients (obese, hypertensive, cardiac, etc.) the correct amount and type of exercise, thus making use of exercise as of any other drug, of which it is imperative to know posology and contraindications; athletes, trainers, and sportsmen in general, who should gear correctly their diet to the type and amount of physical exercise; physical educators, who should be aware of the specific characteristics of the exercise modes they propose to their pupils, as a function of their sex, age, and athletic capacity. However, besides these practical applications, the notions discussed throughout this article bear also a more general interest. Indeed, they allow a better understanding of the motion of man, that is, of the only machine, which besides moving about, also tries to understand how he does it.
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Responses of leptin to short-term fasting and refeeding in humans - A link with ketogenesis but not ketones themselves
Article
  • Dec 1996
  • DIABETES
We investigated the response of leptin to short-term fasting and refeeding in humans. A mild decline in subcutaneous adipocyte ob gene mRNA and a marked fall in serum leptin were observed after 36 and 60 h of fasting. The dynamics of the leptin decline and rise were further substantiated in a 6-day study consisting of a 36-h baseline period, followed by 36-h fast, and a subsequent refeeding with normal diet. Leptin began a steady decline from the baseline values after 12 h of fasting, reaching a nadir at 36 h. The subsequent restoration of normal food intake was associated with a prompt leptin rise and a return to baseline values 24 h later. When responses of leptin to fasting and refeeding were compared with that of glucose, insulin, fatty acids, and ketones, a reverse relationship between leptin and beta-OH-butyrate was found. Consequently, we tested whether the reciprocal responses represented a causal relationship between leptin and beta-OH-butyrate. Small amounts of infused glucose equal to the estimated contribution of gluconeogenesis, which was sufficient to prevent rise in ketogenesis, also prevented a fall in leptin. The infusion of beta-OH-butyrate to produce hyperketonemia of the same magnitude as after a 36-h fast had no effect on leptin. The study indicates that one of the adaptive physiological responses to fasting is a fall in serum leptin. Although the mediator that brings about this effect remains unknown, it appears to be neither insulin nor ketones.
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Serum leptin concentration and fuel homeostasis in healthy man
Article
  • Apr 1997
We studied the interrelationship between the obese gene product serum leptin, insulin and counter-regulatory hormone concentrations and glycogen synthesis in 26 healthy men. A 4-h euglycaemic insulin clamp with muscle biopsies was performed after a resting control day in 26 subjects, and in 14 of them also after heavy, glycogen-depleting (32%, P < 0.01) exercise. Serum leptin concentrations were at baseline 34% (0.67 +/- 0.18 vs. 1.03 +/- 0.13 ng L-1, P < 0.05) lower after the exercise, and rose during hyperinsulinaemia by 56% (to 1.38 +/- 0.19 ng L-1, P < 0.001) and 34% (to 1.05 +/- 0.20 ng L-1, P < 0.01) after the post-exercise and control studies respectively. Basal serum leptin concentration correlated positively with body mass index (r = 0.42, P < 0.05), serum cortisol concentration (r = 0.70, P < 0.001) and the rise in muscle glycogen content during the clamp (r = 0.43, P < 0.05) and inversely with serum growth hormone concentration (r = -0.43, P < 0.05). There was a positive correlation between serum leptin after hyperinsulinaemia and serum insulin concentration during the hyperinsulinaemia (r = 0.42, P < 0.05). After exercise, basal serum leptin level correlated with serum triglyceride concentration (r = 0.82, P < 0.001) and after hyperinsulinaemi serum leptin correlated positively with muscle glycogen content (r = 0.56, P < 0.05). It was concluded that serum leptin concentrations correlate directly with serum insulin, cortisol and triglyceride and inversely with growth hormone concentrations. They are decreased by glycogen-depleting exercise and increase during hyperinsulinaemic clamp. These data suggest that leptin is associated with factors regulating fuel homeostasis and its hormonal control in man.
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Prolonged exercise decreases serum leptin concentration
Article
  • Nov 1997
  • METABOLISM
Serum leptin and free fatty acid concentrations were determined in two groups of subjects undergoing strenuous exercise: 12 men who fasted overnight and then pedaled a stationary ergometer for 2 hours, and 14 nonfasting ultramarathon runners. Blood samples were collected before exercise, immediately after cessation of exercise, and 6 to 24 hours after the end of the exercise period. Two hours of strenuous pedaling following an overnight fast significantly reduced mean leptin levels by 8.3%; free fatty acids were highly increased and correlated well with the decrease in serum leptin (r = .737, P = .01). After 6 hours of rest and refeeding, leptin concentrations recovered to preexercise levels and free fatty acid concentrations were decreased to less than preexercise levels. A similar decrease in serum leptin levels (12.3%) occurred in subjects who fasted overnight and then for a period corresponding to the cycle exercise period. The prolonged exercise of an ultramarathon significantly reduced leptin concentrations by 32% in comparison to prerace levels; free fatty acid concentrations were highly increased, but did not correlate with the change in serum leptin concentrations (r = .366, P = .20). Leptin and free fatty acid concentrations all trended toward prerace levels in blood samples collected 18 to 24 hours after cessation of racing. The results suggest that the negative energy balance of exercise can reduce serum leptin concentrations, but that the significant decrease occurs only at extremes of severity/duration of the exercise-induced negative balance. The possible physiological role of reduced leptin concentrations in response to energy balance and the role of free fatty acids in mediating the response are discussed.
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The effect of exercise on leptin concentration in healthy men and in type 1 diabetic patients
Article
  • Jul 1998
Leptin is a recently discovered hormone that appears as a regulator of energy balance. It is important to know whether leptin concentrations are changed under conditions of altered energy homeostasis. Consequently, we examined the effects of exercise with fasting and exercise with feeding on circulating leptin concentrations in healthy men and in type 1 diabetic patients with normal body weight and well controlled diabetes. Leptin concentrations were determined with radioimmunoassay. During a 3-h cycle ergometer exercise with fasting, leptin decreased by 42% (P < 0.01) in nine healthy men and by 23% (P = 0.05) in eight male type 1 diabetic patients. Leptin fell equally by 12% (P < 0.03) both in nine healthy men and in eight male type 1 diabetic patients who were studied as a resting control group. The absolute fall in leptin in healthy men was similar in the exercise and resting control groups (0.8 +/- 0.1 microgram.L-1 vs 0.8 +/- 0.2 microgram.L-1). However, due to lower leptin concentration before the exercise, the relative decrease (42%) was greater than during the resting control study (12%, P < 0.005). This difference was not seen in the diabetic patients. Fasting leptin concentration correlated positively with BMI (r = 0.75, P < 0.001) and fasting insulin (r = 0.71, P < 0.01) in healthy men as well as with insulin level (r = 0.54, p < 0.05) in type 1 diabetic patients. When exercise was performed with feeding, and this was associated with a significant rise in serum cortisol level (marathon run, 14 healthy men and 7 type 1 diabetic patients), leptin concentration did not change significantly. 1) During morning hours, leptin decreases both in healthy men and in type 1 diabetic patients, reflecting a diurnal variation of leptin concentration and the effect of fasting on leptin concentration. 2) The fall in leptin during morning hours is augmented by physical exercise in healthy men. 3) If exercise is performed with feeding and associated with a rise in serum cortisol level, leptin concentration remains unchanged. These data suggest that although exercise may reduce circulating leptin levels, the effect is small and can be counterbalanced by feeding or a rise in serum cortisol concentration.
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Intensity of acute exercise does not affect serum leptin concentrations in young men
Article
  • Sep 2000
We examined the effects of exercise intensity on serum leptin levels. Seven men (age = 27.0 yr; height = 178.3 cm; weight = 82.2 kg) were tested on a control (C) day and on 5 exercise days (EX). Subjects exercised (30 min) at the following intensities: 25% and 75% of the difference between the lactate threshold (LT) and rest (0.25 LT, 0.75 LT), at LT, and at 25% and 75% of the difference between LT and VO2peak (1.25 LT, 1.75 LT). Kcal expended during the exercise bouts ranged from 150 +/- 11 kcal (0.25 LT) to 529 +/- 45 kcal (1.75 LT), whereas exercise + 3.5 h recovery kcal ranged from 310 +/- 14 kcal (0.25 LT) to 722 +/- 51 kcal (1.75 LT). Leptin area under the curve (AUC) (Q 10-min samples) for all six conditions (C + 5 Ex) was calculated for baseline (0700-0900 h) and for exercise + recovery (0900-1300 h). Leptin AUC for baseline ranged from 243 +/- 33 to 291 +/- 56 ng x mL(-1) x min; for exercise + recovery results ranged from 424 +/- 56 to 542 +/- 99 ng x mL(-1) x min. No differences were observed among conditions within either the baseline or exercise + recovery time frames. Regression analysis confirmed positive relationships between serum leptin concentrations and percentage body fat (r = 0.94) and fat mass (r = 0.93, P < 0.01). We conclude that 30 min of acute exercise, at varying intensity of exercise and caloric expenditure, does not affect serum leptin concentrations during exercise or for the first 3.5 hours of recovery in healthy young men.
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097 km), starting at 9.00 a.m., with a mean exercise time of 1 h 31 min and an estimated mean energy expenditure of 1
  • 39-49
  • G S Roi Casa Di Cura ''s
  • Maria
  • Viale
  • Piemonte
Fax: +39-49-8215810 G.S. Roi Casa di cura ''S. Maria'', Viale Piemonte, 70 Castellanza, Varese, Italy (21.097 km), starting at 9.00 a.m., with a mean exercise time of 1 h 31 min and an estimated mean energy expenditure of 1,400 kcal (5.852 kJ).