scholarly journals Intralipid/heparin infusion suppresses serum leptin in humans

2003 ◽  
pp. 669-676 ◽  
Author(s):  
P Garcia-Lorda ◽  
W Nash ◽  
A Roche ◽  
FX Pi-Sunyer ◽  
B Laferrere

BACKGROUND/AIM: Our previous studies showed that administration of dexamethasone plus food increased serum leptin levels 100% more than dexamethasone alone. We hypothesized that this increase in leptin from the meal could result directly from the provision of fuel metabolites rather than from the meal-induced rise in insulin. In the current study, we tested the effect of an i.v. lipid fuel source (Intralipid 20%/heparin) that would incur only a modest increase in insulin. This study was undertaken because the role of lipid in the regulation of human leptin levels has been controversial, with differing effects reported: stimulatory, inhibitory, or no effect at all. METHODS: In order to evaluate how lipids affect serum leptin in humans, we administered the following to seven lean, healthy, fasting subjects: (i) Intralipid 20% at 0.83 ml/kg.h plus heparin (800 IE/h) infused i.v. for 7 h (LIPID), (ii) LIPID with one initial pulse of insulin (0.09 U/kg) given s.c. (LIPID+INS), (iii) LIPID with dexamethasone (2 mg i.v. push) given at the start of the infusion (LIPID+DEX), and (iv) LIPID with insulin plus dexamethasone (LIPID+INS+DEX). Control trials in another 14 subjects matched hormonal conditions but lacked the LIPID infusion. Blood levels were collected over 8 h for determination of free fatty acids (FFA), glucose, insulin, and leptin under each experimental condition. RESULTS: Over the 420 min of LIPID infusion, FFA levels rose four-fold from 0.28+/-0.05 mmol/l to 0.99+/-0.05 mmol/l. Serum leptin levels were suppressed by 10-20% in the LIPID condition as compared with control (no LIPID) between 90 min (P=0.008) and 360 min (P=0.045). LIPID+DEX did not increase leptin. A pulse of insulin (INS) increased serum insulin levels to 49.9+/-6.1 U/ml at 90 min and increased serum leptin by 21.3+/-6.6% at 480 min (P=0.054). LIPID decreased leptin in the face of this insulin-induced increase (LIPID+INS), between 360 min (P=0.017) and 420 min (P=0.003), with a 23% suppressive effect at 420 min. LIPID+DEX elevated leptin levels by 112.5+/-35.8% at 480 min (P=0.037), however, the Intralipid/heparin infusion did not blunt the rise of leptin under these conditions. CONCLUSIONS: These data showed that Intralipid/heparin: (i) are not sufficient to trigger the effect of dexamethasone on leptin, (ii) have an acute inhibitory effect on both fasting and insulin-stimulated leptin levels, and (iii) that this inhibitory effect cannot reverse the strong stimulatory effect of dexamethasone and insulin on serum leptin.

2002 ◽  
pp. 181-188 ◽  
Author(s):  
A Elimam ◽  
C Marcus

BACKGROUND: In a previous study, we reported a 4-fold increase in serum leptin following total parenteral nutrition given after surgery. We hypothesised that the perioperative fasting and stress contributed to this, possibly mediated by increased serum insulin and cortisol. OBJECTIVE: To test the hypothesis that fasting, in combination with glucocorticoids, sensitises the leptin response to subsequent energy intake. DESIGN: Healthy volunteers were randomised into two groups, one group received dexamethasone (DEX), 0.1 mg twice daily for 3 days, while the other group served as a control. Each group was then subdivided into two feeding protocols. Protocol 1, where a standard meal was given at 0, 24, 36 and 48 h and protocol 2 where the same meal was given at 0 and 48 h. Blood samples were drawn before, as well as every other hour during the study period for determination of serum leptin, insulin, glucose and cortisol concentrations. RESULTS: In all groups serum leptin increased significantly following each meal (P<0.01). The rise in serum leptin in response to the standard meal was higher when the meal was taken in the evening (P<0.001) or following longer duration of fasting (P<0.02). In those fasting for 48 h, leptin decreased by 60% and showed no diurnal variation. DEX intake increased leptin concentrations in those fasting for short periods (P<0.02) but not for 48 h. CONCLUSIONS: Long durations of fasting sensitise the response of leptin to subsequent energy intake and abolish the DEX-induced upregulation of leptin. Meal timing is an important factor determining the leptin diurnal rhythm, but other factors must contribute since the leptin response to a standard meal taken in the evening was greater than to the same meal taken in the morning.


2021 ◽  
Vol 11 (15) ◽  
pp. 6948
Author(s):  
Gabriele Cervino ◽  
Sergio Sambataro ◽  
Chiara Stumpo ◽  
Salvatore Bocchieri ◽  
Fausto Murabito ◽  
...  

The aim of this study is to demonstrate the use and the effectiveness of cephalometry and golden proportions analysis of the face in planning prosthetic treatments in totally edentulous patients. In order to apply this method, latero-lateral and posterior-anterior X-rays must be performed in addition to the common procedure. Two main concerns for totally edentulous patients are the establishment of the vertical dimension and the new position of the occlusal plane. The divine proportion analysis was carried out by the use of a golden divider. The prosthetic protocol was divided into three steps and a case was selected for better understanding. Referring to the golden relations, if the distance from the chin to the wing of the nose is 1.0, the distance from the nose to eye is 0.618. This proportion is useful and effective in determining the correct prosthetic vertical dimension. The incisal margin of the lower incisor must be positioned between Point A (A) and protuberance menti (Pm) according to the gold ratio 0.618 of the total height A-Pm. Posteriorly the occlusal plane must be placed 2 mm below the divine occlusal plane (traced from the incisal margin of lower incisors to Xi point). A prosthesis made in accordance with cephalometric parameters and divine proportions of the face helps to improve the patient’s aesthetics, function and social personality.


1991 ◽  
Vol 131 (1) ◽  
pp. 87-94 ◽  
Author(s):  
A. W. Nangalama ◽  
G. P. Moberg

ABSTRACT In several species, glucocorticoids act directly on the pituitary gonadotroph to suppress the gonadotrophin-releasing hormone (GnRH)-induced secretion of the gonadotrophins, especially LH. A mechanism for this action of these adrenal steroids has not been established, but it appears that the glucocorticoids influence LH release by acting on one or more post-receptor sites. This study investigated whether glucocorticoids disrupt GnRH-induced LH release by altering the liberation of arachidonic acid from plasma membrane phospholipids, a component of GnRH-induced LH release. Using perifused ovine pituitary tissue, it was established that exposure of gonadotrophs to 1–1000 nmol cortisol/l for 4 h or longer significantly reduced GnRH-stimulated LH release with the maximal inhibitory effect being observed after 6 h of exposure to cortisol. This suppressive effect of cortisol could be reversed by administration of arachidonic acid, which in its own right could stimulate LH release from ovine pituitary tissue. Furthermore, the inhibitory effect of cortisol on GnRH-stimulated LH release could be directly correlated with decreased pituitary responsiveness to GnRH-stimulated arachidonic acid liberation, consistent with our hypothesis that glucocorticoids can suppress GnRH-induced secretion of LH by reducing the amount of arachidonic acid available for the exocytotic response of GnRH. Journal of Endocrinology (1991) 131, 87–94


1997 ◽  
Vol 272 (6) ◽  
pp. R1809-R1815 ◽  
Author(s):  
R. B. Harris

The objective of this experiment was to confirm whether changes in serum leptin and leptin expression were consistent with it being the "lipostatic" factor implicated by earlier parabiosis studies. Lean (+/?) and obese (ob/ob) female C57B1/6J-ob mice were parabiosed (lean-ob/ob) at 7 wk of age. Controls were ob/ob-ob/ob and lean-lean pairs, and single lean and ob/ob mice. Pairs were maintained for 50 days. In ob/ob members of lean-ob/ob pairs serum insulin was normalized, food intake was suppressed, and body fat was reduced by 14%. Lean partners of ob/ob mice had a reduced rectal temperature and experienced a 37% reduction in body fat. Despite loss of fat, serum leptin and adipose leptin mRNA expression were unchanged in lean partners of ob/ob mice. These results suggest that, in lean-ob/ob parabiotic pairs, the ob/ob mouse responds to leptin originating in the lean parabiont, whereas the lean partner responds to a circulating signal, originating in the ob/ob mouse, that maintains leptin expression at inappropriate levels for the degree of adiposity of the lean animal.


1970 ◽  
Vol 1 (4) ◽  
pp. 102-105 ◽  
Author(s):  
M Alam ◽  
MM Rahman ◽  
MJ Foysal ◽  
MN Hossain

The toxic effects of four disinfectants viz., copper sulfate (CuSO4), potassium permanganate (KMnO4), methylene blue and malachite green on fish and fish pathogenic bacteria Aeromonas sp., Pseudomonas fluorescens, Edwardsiella sp. and Flavobacterium sp. were investigated. Lethal concentration of the disinfectants to fingerlings of Labeo rohita was determined in aquarium by standard method. Lethal concentration of copper sulfate (CuSO4), potassium permanganate (KMnO4), methylene blue and malachite green against fish were found in 0.75ppm, 7ppm, 6ppm and 0.5ppm at 21.4hrs, 18hrs, 9.5hrs and 1.40hrs, respectively. Methylene blue at 4ppm and 5ppm concentration inhibited the growth of Pseudomonas fluorescens and 6ppm concentration suppressed the growth of Aeromonas sp. Copper sulfate (CuSO4) was effective only against Edwardsiella sp at concentration of 10ppm and 8ppm. Malachite green repressed the growth of all four tasted bacteria at a concentration of 1ppm. Potassium permanganate (KMnO4) was failed to exhibit any inhibitory effect on the bacteria even at 30ppm concentration. DOI: http://dx.doi.org/10.3329/ijns.v1i4.9738 IJNS 2011 1(4): 102-105


2013 ◽  
Vol 726-731 ◽  
pp. 1755-1759
Author(s):  
Jun Liu ◽  
Jin Xia Nie

In order to study the soil amend agent how to suppress the function of the vegetables absorb Pb, the Pb was added in the experimental soil in pakchoi pot, The lime and peanut dry cake were added to the experimental soil as modifier, and the varying concentrate of modifiers, lead effect on pakchoi biomass and lead accumulate were discussed in this paper. Through the determination of Pb content of aboveground and underground part of pakchoi by ICP, the lime and peanut dry cake can resist lead absorption were proved, and the lime achieved better inhibitory effect of the two. By analyzed the BCF of two parts of pakchoi, two types of modifiers had proved can reduce the pakchoi BCF of Pb in the soil. The lime was more efficient than the peanut dry cake on reducing BCF of Pb.


Media Wisata ◽  
2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Sri Larasati

The purpose of this research is to know wtether knowledge, skill, responsiveness and communication skill influence in job competition for graduate student from Sekolah Tinggi Pariwisata AMPTA. The population in this study are student pf Sekolah Tinggi Pariwisata SMPTA that graduated in 2013 until 2016, the total population in this studt is 702 and 200 respondents who have worked taken as samples, samples were taken with non probability sampling technique and accidental sampling approach. Sampling approach using regression equations obtained results that through test results F (regression analysis jointly) may note that the value of F = 147.104 count with the significance of 0.000 < 0.05. The test results of the test F reinforced with testing the determination of the coefficient that shows the value of 74.6%) (0.746. From Test t (partially) can result in variable knowledge with a value of t = 3,173 and significance of the value 0002 < 0.05, variable skill with a value of t = 2,949 and value the significance of 0.004 < 0.05, variable attitude with a value of t = 2,688 and value the significance of 0.008 < 0.05, variable communication skill with a value of t = value and significance of 4,497 0000 < 0.05. From the above results can be known that the hypothesis posed was not proven in other words that all of these variables can be said to have a positive and significant effect simultaneously as well as partial toward the ability of STP graduates AMPTA in the face of competition in the world of work


Sign in / Sign up

Export Citation Format

Share Document