scholarly journals IGF-I-induced enhancement of contractile response in organ-cultured aortae from diabetic rats is mediated by sustained thromboxane A2 release from endothelial cells

2005 ◽  
Vol 186 (2) ◽  
pp. 367-376 ◽  
Author(s):  
Tsuneo Kobayashi ◽  
Takayuki Matsumoto ◽  
Katsuo Kamata
Keyword(s):  
Endothelial Cells ◽  
Organ Culture ◽  
Contractile Response ◽  
Diabetic Rats ◽  
Receptor Expression ◽  
Diabetic Rat ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free ◽  
Igf I

We have investigated the mechanisms underlying the changes in vascular contractile responsiveness induced by insulin and IGF-I in established streptozotocin-induced diabetic rats. The contractile response to noradrenaline (NA) in organ-cultured diabetic rat aortae cultured with insulin or IGF-I was significantly greater than the corresponding responses in (a) diabetic rat aortae cultured in serum-free medium and (b) control rat aortae cultured with insulin or IGF-I. In aortae from which the endothelium was removed after organ culture the contractile response to NA was greater in those cultured with insulin or IGF-I than in those cultured in serum-free medium. This was not true of aortae endothelium denuded before organ culture. The IGF-I-induced enhancement was prevented by treatment with indomethacin (cyclo-oxygenase inhibitor), SQ29548 (thromboxane (TX) A2 receptor antagonist) or fregrelate (TXA2 synthase inhibitor). IGF-I-induced production of TXB2, a metabolite of TXA2, was greater in diabetic than in control aortae and was attenuated by endothelium denudation, indomethacin or AG1024 (IGF-I receptor inhibitor). The expression of the protein and mRNA for the IGF-I receptor (as assessed by RT-PCR and immunohistochemistry) was markedly increased within endothelial cells in diabetic aortae but only slightly increased within smooth muscle cells (versus control rat aortae). Thus, the NA-induced contractile response in aortae from diabetic rats was enhanced by both insulin and IGF-I and this enhancement may be mediated by sustained cyclo-oxygenase-dependent TXA2 production from endothelial cells. The observed enhancement of IGF-I receptor expression within endothelial cells may be causally related to the potentiation of vascular contractility and the increase in TXA2 production.

Hemoglobin Enhances the Binding of Bacterial Endotoxin to Human Endothelial Cells

1996 ◽  
Vol 76 (02) ◽  
pp. 258-262 ◽  
Author(s):  
Robert I Roth
Keyword(s):  
Endothelial Cells ◽  
Binding Protein ◽  
Bacterial Endotoxin ◽  
Dependent Manner ◽  
Serum Free Medium ◽  
Free Medium ◽  
Human Endothelial Cells ◽  
Serum Factors ◽  
Serum Free ◽  
Lps Binding

SummaryHuman endothelial cells, when incubated with bacterial endotoxin (lipopolysaccharide, LPS), modify their surface in association with prominent production of procoagulant tissue factor (TF) activity. This deleterious biological effect of LPS has been shown previously to be enhanced approximately 10-fold by the presence of hemoglobin (Hb), a recently recognized LPS binding protein that causes disaggregation of LPS and increases the biological activity of LPS in a number of in vitro assays. The present study was performed to test the hypothesis that Hb enhances the LPS-induced procoagulant activity of human umbilical vein endothelial cells (HUVEC) by increasing LPS binding to the cells. The binding of 3H-LPS to HUVEC was determined in the absence or presence of Hb or two other known LPS-binding proteins, human serum albumin (HSA) and IgG. LPS binding was substantially increased in the presence of Hb, in a Hb concentration-dependent manner, but was not increased by HSA or IgG. Hb enhancement of LPS binding was observed in serum-free medium, indicating that there was no additional requirement for any of the serum factors known to participate in the interaction of LPS with cells (e.g., lipopolysaccharide (LPS)-binding protein (LBP) and soluble CD14 (sCD14)). Hb enhancement of LPS binding also was observed in the more physiologic condition of 100% plasma. LPS-induced TF activity was stimulated by Hb, but not by HSA or IgG. In serum-free medium, TF activity was not stimulated under any of the conditions tested. Ultrafiltration of LPS was dramatically increased after incubation with Hb but not with HSA or IgG, suggesting that LPS disaggregation by Hb was responsible for the enhanced binding of LPS to HUVEC and the subsequent stimulation of TF activity.

THE INFLUENCE OF SERUM ON THE UPTAKE, CONVERSION AND ACTION OF DIHYDROTESTOSTERONE IN RAT PROSTATE GLANDS IN ORGAN CULTURE

1975 ◽  
Vol 64 (2) ◽  
pp. 289-297 ◽  
Author(s):  
ILSE LASNITZKI ◽  
HILARY R. FRANKLIN
Keyword(s):  
Organ Culture ◽  
Horse Serum ◽  
Target Tissue ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free ◽  
Human Pregnancy ◽  
Human Male ◽  
Columnar Cells

SUMMARY The influence of serum on the uptake, conversion and action of dihydrotestosterone in relation to the sex steroid binding protein, TeBG, has been investigated in rat ventral prostates in organ culture. The organs were incubated with [1,2-3H]dihydrotestosterone in: (1) serum-free medium, (2) horse serum, foetal and newborn bovine serum or (3) human male and human pregnancy serum. With all sera the uptake of dihydrotestosterone fell with rising serum concentration, at first steeply and then more gradually. At the same concentration, the uptake was significantly lower in explants incubated with human pregnancy serum than in those kept with human male serum. The conversion of dihydrotestosterone to androstanediol followed the same pattern and less androstanediol was formed in the presence of pregnancy serum. Since pregnancy serum contains higher amounts of TeBG than male serum, the lowered uptake suggests that only the free hormone was available to the target organ. Addition of unlabelled dihydrotestosterone resulted in a higher uptake than that measured in explants incubated with the labelled steroid only. The effect of the human sera on uptake and conversion was correlated with the androgenic activity of dihydrotestosterone applied at physiological concentrations and expressed as the percentage of secretory columnar cells present. The degree of maintenance closely corresponded to the uptake of the hormone. In serum-free medium, the number of columnar cells approached the values found in vivo, with male serum their number, though reduced, was still substantial, with pregnancy serum it was extremely low. It is concluded that the amounts of TeBG present in serum regulate the supply of the hormone to the target tissue and thus control its biological action.

Adrenergic differentiation and SSR2(a) receptor expression in CAD-cells cultured in serum-free medium

2003 ◽  
Vol 42 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Sayed Hossein Hashemi ◽  
Jia-Yi Li ◽  
Roland Faigle ◽  
Annica Dahlström
Keyword(s):  
Receptor Expression ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free ◽  
Cad Cells ◽  
Cells Cultured

scholarly journals Isolated porcine ovarian follicles as a model for the study of hormone and growth factor action on ovarian secretory activity

1998 ◽  
Vol 159 (2) ◽  
pp. 313-321 ◽  
Author(s):  
AV Sirotkin ◽  
AV Makarevich ◽  
J Kotwica ◽  
PG Marnet ◽  
HB Kwon ◽  
...  
Keyword(s):  
Growth Factor ◽  
Ovarian Follicles ◽  
Serum Free Medium ◽  
Free Medium ◽  
Ovarian Steroid ◽  
Serum Free ◽  
Factor Binding ◽  
Estradiol Secretion ◽  
Igf I ◽  
Igfbp 3

The aim of our in vitro experiments with isolated porcine ovarian follicles was to study the effects of gonadotropins, GH, IGF-I and oxytocin (OT) on release of ovarian steroid, OT, IGF-I, insulin-like growth factor-binding protein-3 (IGFBP-3), prostaglandin F (PGF), prostaglandin E (PGE) and cAMP. It was found that quarters of ovarian follicles cultured for 8 days produced significant amounts of progesterone, estradiol-17 beta, OT and IGFBP-3 with peaks of accumulation from the 3rd to the 8th day of culture. Addition of serum promoted progesterone, estradiol and OT release, whilst accumulation of IGFBP-3 was maintained to a greater extent in serum-free medium. GH (10 ng/ml or above) was able to inhibit androstenedione, OT, PGF and IGFBP-3, to stimulate IGF-I and cAMP, and to alter testosterone and PGE release by follicles cultured in serum-supplemented and/or serum-free medium. IGF-I (10 ng/ml or more) inhibited androstenedione and PGF secretion, stimulated testosterone, estradiol, OT and cAMP production, but did not influence progesterone, IGFBP-3 or PGE output in these conditions. OT (100 ng/ml) was able to inhibit androstenedione and to stimulate testosterone, IGF-I, PGF and PGE, but not estradiol or IGFBP-3 release. A stimulatory effect of LH on progesterone and OT and an inhibitory influence of LH on estradiol secretion in the serum-supplemented medium were observed. FSH in these conditions stimulated OT, but not progesterone or estradiol secretion. The use of this experimental model suggests the involvement of gonadotropins, OT, GH and IGF-I in the control of ovarian steroid and nonapeptide hormone, growth factor, growth factor-binding protein, prostaglandin and cyclic nucleotide production. The stimulatory effect of GH on IGF-I, and the stimulatory influence of IGF-I on OT, as well as coincidence of the majority of effects of IGF-I and OT, suggest the existence of a GH-IGF-I-OT axis. On the other hand, the different patterns of action of GH and IGF-I on OT, estrogen and IGFBP-3 suggest that part of the GH effect on ovarian cells is IGF-I independent.

High density lipoproteins and the growth of vascular endothelial cells in serum-free medium

In Vitro ◽  
1981 ◽  
Vol 17 (6) ◽  
pp. 519-530 ◽  
Author(s):  
J.-P. -P. Tauber ◽  
J. Cheng ◽  
S. Massoglia ◽  
D. Gospodarowicz
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
High Density ◽  
High Density Lipoproteins ◽  
Vascular Endothelial ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free
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