The Opposite Effect of L-kynurenine and Ahr Inhibitor Ch223191 on Apoptotic Protein Expression in Pancreatic Carcinoma Cells (Panc-1).

BACKGROUND: L-kynurenine, derivate of L-tryptophan, is synthetized by indoleamine 2,3-dioxygenase (IDO). The effects of L-kynurenine depend on its binding to an aryl hydrocarbon receptor (AhR). OBJECTIVE: The aim of this study was to investigate the changes within the apoptotic pathway in PANC-1 cells subjected to L-kynurenine or L-tryptophan considering the production of anti-apoptotic proteins from the IAPs and Bcl-2 family, as well as the regulation of NF-κB signaling. METHODS: The investigated substances were added alone or in combination with the AhR inhibitor (CH223191) to cultures of PANC-1 cells. Cytoplasmic and nuclear proteins were analyzed by immunoblotting and cells were incubated with the investigated substances to determine cytotoxicity and proliferative effects. RESULTS: Incubation of PANC-1 cells with L-kynurenine or L-tryptophan resulted in the increase in antiapoptotic cIAP-1, cIAP-2, XIAP and Bcl-2 expression and a decrease in pro-apoptotic Bax. These changes were accompanied by the reduction of active caspases -9, -3 and PARP-1. The treatment leads to translocation and enhanced production of nuclear NF-κB p50 and Bcl-3. Incubation of the cells with AhR blocker either alone or together with L-kynurenine or L-tryptophan resulted in the opposite effect, leading to the downregulation of IAPs and Bcl-2, upregulation of Bax and caspases expression. CONCLUSION: 1) L-kynurenine and its precursor promote anti-apoptotic effects through the modulation of IDOdependent pathway and regulation of IAPs, Bcl-2 and NF-κB family members in pancreatic carcinoma cells 2) inhibition of AhR by CH223191 exerts an apoptosis-promoting effect, and this observation might suggest the potential use of this compound in pancreatic cancer therapy.

[Effect of free fatty acids on CYP19A1 (aromatase) gene expression in human adipose tissue stromal vascular fraction cells].

Aromatase plays an important role in the estrogen biosynthesis. Its gen (CYP19A1) is expressed in preadipocytes (stromal vascular fraction, SVF) of adipose tissue. Estrogens are found to be protective for metabolism homeostasis, and cardiovascular system. Disturbed dietary and endogenous fatty acids (FAs) turnover is responsible for development of metabolic syndrome and it complications. Aim of the work was to investigate the effect of physiological concentrations of acids: arachidonic (AA), oleic (OA), palmitynoic (PA) and eikozapentaenoic (EPA) on CYP19A1 expression in differentiating human SVF, able to form adipocytes as well as endothelial cells. Material and Methods: Human (n=38 healthy woman) SVF cells were isolated from subcutaneous adipose tissue harvested intrasurgery. SVF cells were incubated in proadipogenic or angiogenic media to obtain adipocytes (Adipo-SVF) or endothelial (Angio-SVF) cells (confirmed by microarray). Changes in the CYP19A1 expression induced by 24hs incubation in the presence of FAs (10 ­ 30 µM )were monitored by the Real time PCR (qRT -PCR). Results: The aromatase gene expression correlated positively with BMI of patients, but only in group of obese or overweight women. The negative correlation was found in the group of young, slim women. The highest expression of aromatase was found in the fresh, not differentiated SVF. In differentiating to endothelial cells (Angio - SVF) OA inhibited (p=0.008), when n-3 polyunsaturated AA activated (p=0.003) the CYP19A1 gene expression. In differentiating to preadipocytes (Adipo-SVF) AA significantly (p=0.031) inhibited CYP19A1 expression. Conclusion: The changes in the aromatase gene expression in differentiating SVF has been confirmed. The different effect of the dietary FA (OA vs. AA) on the aromatase gene expression argue for the role of the locally formed proangiogenic estrogens.

Bilateral vagotomy attenuates the severity of secretagogue-induced acute pancreatitis in the rat.

PURPOSE: We assessed the effect of bilateral vagotomy (BV) on the course of acute caerulein-induced pancreatitis (AP) in the rat. MATERIAL/METHODS: The study was performed on Wistar rats surgically prepared by subdiaphragmatic BV. Control group underwent sham operation. Four days later, AP was induced by subcutaneous injection of caerulein (25 µg/kg/5h) to the conscious animals with or without BV. After administration of caerulein the blood samples were taken for determination of serum lipase activity and interleukin-10 (IL-10) concentration. Pancreatic tissue samples were subjected to histological examinations and to the measurement of lipid peroxidation products (MDA+4-HNE) concentration and the activity of an antioxidant enzyme - glutathione peroxidase (GPx). After application of caerulein pancreatic blood flow was measured by laser Doppler flowmetry. RESULTS: AP was manifested by oedema and neutrophil infiltration of the pancreatic tissue and accompanied by significant increases of serum lipase activity, serum concentration of IL-10 and pancreatic concentration of MDA+4HNE (ca. 50×, 2× and 4× respectively p ≥ 0.05). Pancreatic activity of GPx and pancreatic blood flow were decreased (both by 60%). In vagotomised rats with AP serum lipase activity and pancreatic concentration of MDA+4-HNE were lower whereas Il-10 concentration and pancreatic activity of GPx, as well as pancreatic blood flow were significantly higher as compared to AP rats with intact vagal nerves. In AP rats with vagotomy all histological signs of pancreatitis were significantly reduced. CONCLUSIONS: Bilateral vagotomy resulted in the significant attenuation of caerulein-induced pancreatitis in the rat.

Metabolic effects of the HIV protease inhibitor--saquinavir in differentiating human preadipocytes.

BACKGROUND: The iatrogenic, HIV-related lipodystrophy is associated with development of the significant metabolic and cardiovascular complications. The underlying mechanisms of antiretroviral (ARV) drugs are not completely explored. METHODS: The aim of the study was to characterize effects of the protease inhibitor (PI)--saquinavir (SQV) on metabolic functions, and gene expression during differentiation in cells (Chub-S7) culture. RESULTS: SQV in concentrations observed during antiretroviral therapy (ART) significantly decreased mitochondrial membrane potential (MMP), oxygen consumption and ATP generation. The effects were greater in already differentiated cells. This was accompanied by characteristic changes in the expression of the genes involved in endoplasmic reticulum (ER) stress, and differentiation (lipid droplet formation) process such as: WNT10a, C/EBPa, AFT4, CIDEC, ADIPOQ, LPIN1. CONCLUSIONS: The results indicate that SQV affects not only metabolic (mitochondrial) activity of adipocytes, but affects the expression of genes related to differentiation and to a lesser extent to cell apoptosis.

Influence of fatty acids on mitochondrial metabolism of adipocyte progenitors and endothelial cells.

CONTEXT: In obesity, the cells are exposed to excessive amounts of nutrients, especially free fatty acids (FFAs) that induce a variety of metabolic changes. OBJECTIVE: We investigated the effect of FFAs on the mitochondrial function in different cell populations under stress conditions. METHODS: Human adipose tissue progenitor cells (SVF) or endothelial cells (HUVECs) were incubated with 30µM of selected saturated or unsaturated FFA for 24 h, at times supplemented with 5ng/mL tumour necrosis factor alpha (TNFα) for the last 4 h. Changes in oxygen respiration rate, mitochondrial membrane potential (mitoMP) and total ATP content were monitored. RESULTS: Saturated palmitic acid demonstrated no effect, while a selection of unsaturated FFAs ameliorated metabolism of the progenitor SVF cells. TNFα either did not affect or nullified some of the favourable FFA-induced effects. CONCLUSIONS: The mitoMP was the most sensitive parameter reflecting positive impact of the unsaturated FFA on the adipose SVF cells' metabolism.

Modulation of the human preadipocyte mitochondrial activity by beta-carotene.

Increased ROS generation by the overload by metabolic substrates mitochondria paralleled by decrease of antioxidant activity are typical events found in metabolic syndrome and diabetes type 2. Metabolites of beta-carotene (BC) such as retinoic acid (RA), as well as low concentration of reactive oxygen species (ROS) modify the mitochondrial bioenergetic function. The aim of the study was to investigate the effect of beta-carotene on mitochondrial activity in human preadipocytes. BC used in concentrations, 10 or 30 µM, decreased mitochondrial membrane potential, inhibited mitochondrial respiration and decreased cellular ATP content. We conclude, that BC, the known antioxidant may decrease oxidative phosphorylation capacity of mitochondria.

Connexin 43 and metabolic effect of fatty acids in stressed endothelial cells.

Changes in the inner mitochondrial membrane potential (∆ψ) may lead either to apoptosis or to protective autophagy. Connexin 43 (Cx43), a gap junction protein, is suggested to affect mitochondrial membrane permeability. The aim of our study was to analyze Cx43 gene expression, Cx43 protein localization and mitochondrial function in the human endothelial cells stressed by dietary-free fatty acids (FFA) and TNFα. Human endothelial cells (HUVECs) were incubated with (10-30 uM) palmitic (PA), oleic (OA), eicosapentaenoic (EPA) or arachidonic (AA) acids for 24 h. TNFα (5 ng/ml) was added at the last 4 h of incubation. The Cx43 gene expression was analyzed by the quantitative real-time PCR. The Cx43 protein concentrations in whole cells and in the isolated mitochondria were measured. Changes in ∆ψ and Cx43 localization were analyzed by flow cytometry or fluorescence microscopy. Generated ATP was measured by a luminescence assay. TNFα, PA and OA significantly decreased ∆ψ, while AA (P = 0.047) and EPA (P = 0.004) increased ∆ψ value. Preincubation with EPA or AA partially prevented the TNFα-induced decrease of ∆ψ. Incubation with AA resulted in up-regulation of the Cx43 gene expression. AA or PA significantly increased Cx43 protein content; however, presence of TNFα in general aggravated the negative effect of FFA. Only EPA was found to increase ATP generation in HUVECs. The fatty acid-specific induction of changes in Cx43 expression and protein concentration as well as the normalization of ∆ψ and increase of ATP generation seem to be the separate, independent mechanisms of FFA-mediated modulatory effect in the human endothelial cells pathology.

[Growth factors and cytokines (TGFBeta, bFGF and IGF-1) and cardiac left ventricular hypertrophy in hypertension]. / Czynniki wzrostu i cytokiny (TGFBeta, bFGF i IGF-1) a przerost miesnia lewej komory serca w nadcisnieniu t tetniczym.

One of the most frequent types of organ damage developing in the course of hypertension is left ventricular hypertrophy (LVH). The percentage of hypertensive patients with LVH, assessed with echocardiographic method, amounts to 20-60%, depending on blood pressure level and duration of hypertension. This review includes current opinions on the role of transforming growth factor Beta1 (TGFP31), basic fibroblast growth factor (bFGF, FGF2), and insulin-like growth factor-1 (IGF-1) in the development of LVH in the course of hypertension. TGFBeta1 is a cytokine involved in the regulation of proliferation and cell differentiation. Its action is mainly directed towards the connective tissue cells, which it stimulates into production of collagen I and III. Increased levels of TGFbeta1 have been found both in animal models and in patients with hypertension and LVH. Growth factors bFGF and IGF-1 activate cell proliferation and have anti-apoptotic action. The role of bFGF and IGF-1 has been demonstrated in animal models; however, results of observations in subjects with hypertension and LVH are inconsistent. Discussed growth factors and cytokines and cell signalling pathways related to them might in future appear as targets for therapeutic intervention.

Changes in germ cell population in young and adult female mice from two inbred strains: CBA/Kw and KE.

Female mice from two inbred strains CBA/Kw and KE differ markedly in fertility. The gametes of females from KE strain are of poorer quality than those of CBA/Kw. We analyzed the number of oocytes per ovary in KE and CBA/Kw mice aged 5, 25, 90, 180 and 360 days. The ovaries were dissected and processed according to the routine histological methods. In case of five-day-old females we used a modified distributed point counting method while in order to examine the gonads of older females, the nucleoli counting method was applied. In general, we observed gradual decrease in germ cell number throughout the whole life of females from both strains. The noticeable wave of oocyte loss occurs between 5th and 25th days of life. The mice from KE inbred strain on day 25th (1650 +/- 322 vs. 1140 +/- 210) and 90(th) (1040 +/- 211 vs. 692 +/- 89) days have significantly (p<0.005) more germ cells than the females from CBA/Kw strain. In older females the differences were not statistically significant. Interestingly, CBA/Kw females were found to have more rapid loss of primordial follicles throughout their lives. This can explain their shortened reproductive lifespan which was observed earlier.