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Associations of cholesterol and vitamin D metabolites with the risk for development of high grade colorectal cancer

Summary

Background

Vitamin D deficiency is repeatedly reported in colorectal cancer (CRC). Since cholesterol and vitamin D share common precursor 7-dehydrocholesterol (7-DHC), it would be important to explore the associations of key vitamin D metabolites and serum lipid parameters in patients with high and low grade CRC. The aim of this study was to analyze relationships between serum 25(OH)D3, 24,25(OH)2D3 and 7-DHC levels and serum lipids in patients with CRC, and to evaluate their potential for prediction of risk for development of high grade CRC.

Methods

We recruited 82 patients CRC and 77 controls. 7-DHC, 25(OH)D3 and 24,25(OH)2D3 were quantified by LC-MS/MS methods.

Results

7-DHC, 25(OH)D3 and vitamin D metabolic ratio (VDMR) were significantly lower in CRC patients than in control group (P<0.001, P<0.010, P<0.050 and P<0.050, respectively). 25(OH)D3 levels were higher in patients with grade I CRC when compared to grade II (P<0.050). All vitamin D metabolites positively correlated with total cholesterol (TC) concentration in CRC patients. 25(OH)D3 was significant predictor of increased CRC risk (P<0.010). After adjustment for TC concentration, 25(OH)D3 lost its predictive abilities. However, 25(OH)D3 remained significant predictor of poorly differentiated type of cancer (P<0.050).

Conclusions

We found significant positive association between vitamin D status and serum total cholesterol. Although low 25(OH)D3 was found to be a significant risk factor for CRC development, the obtained results primarily suggest profound impact of cholesterol level on vitamin D status in CRC. However, our results suggest that low 25(OH)D3 might independently contribute to development of poorly differentiated tumor.

Open access
Comparison between bone alkaline phosphatase immunoassay and electrophoresis technique in hemodialysis patients

Summary

Background

Problem of the variability between the different methods using for bone alkaline phosphatase (bALP) determination greately influences the clinical significance of bALP as direct marker of bone metabolism. The aim of this study was to compare immunoassay with electrophoresis technique for bALP determination.

Methods

We measured bALP in 71 patients on hemodialysis with agar gel electrophoresis (ISO-PAL, SEBIA) and immunoassay (OSTASE, Beckman Coulter).

Results

The analyzed methods showed significant correlation (Spearman’s rho: 0.776, P < 0.01), but we found statistically significant (P < 0.01) positive bias (27%) for the results measured by immunoassay. In support of this, using electrophoresis technique we have detected presence of the intestinal isoenzymes of alkaline phosphatase in 55% of patients with median value of 30% of the total alkaline phoshatase and presence of liver-2 alkaline phosphatase isoform in 42% of patients with median value of 16.6%. The Kendall’s W of 0.787 (P<0.0001) revealed significant concordance between two analysed methods. Cusum test showed no significant deviation from linearity (P=0.850).

Conclusions

Despite good agreement between immunoassay methods and electrophoresis technique for bALP determination, interchangeability between these two methods is questionable. Although immunoassays are increasingly used, as fully automated methods, in a large number of laboratories and become routine methods for bALP determination, it should be beared in mind, besides various interferences, also the heterogeneity of the bALP itself, especially in patients on hemodialysis.

Open access
Determination of non-cholesterol sterols in serum and HDL fraction by LC/MS-ms: Significance of matrix-related interferences

Summary

Background

Non-cholesterol sterols (NCS) are promising biomarkers for estimation of cholesterol homeostasis properties. In addition, determination of NCS in high-density lipoprotein (HDL) fraction (HDL-NCS) could provide information on cholesterol efflux. However, matrix effects interfere in liquid chromatography–mass spectrometry (LC-MS) analysis of NCS, thereby impairing the method sensitivity. The aims of this study were development, optimization and validation of LC-MS method for quantification of NCS in serum and HDL-NCS. Additionally, matrix effect interferences and methods application in individual serum samples were examined.

Methods

HDL precipitating reagent was used for HDL isolation. Matrix effect was examined by comparing different surrogates by simple regression analysis. Validation was conducted according to the FDA-ICH guideline. 20 healthy volunteers were recruited for testing of method application.

Results

The observed matrix effect was 30%, and matrix comparison showed that cholesterol was the dominant contributor to the matrix effect. Cholesterol concentration was adjusted by construction of the calibration curve for serum and HDL fraction (5 mmol/L and 2.5 mmol/L, respectively). The intra- and inter- run variabilities for NCSs were 4.7–10.3% for serum NCS and 3.6–13.6% for HDL-NCS and 4.6–9.5% for serum NCSs and 2.5–9.8% for HDL-NCS, respectively. Recovery studies showed satisfactory results for NCSs: 89.8–113.1% for serum NCS and 85.3–95.8% for HDL-NCS.

Conclusions

The method was successfully developed and optimized. The matrix interference was solved by customising calibration curves for each method and sample type. The measurement of NCS in HDL fraction was proposed for the first time as potentially useful procedure in biomedical researches.

Open access
Pentoxifylline with metformin treatment improves biochemical parameters in patients with nonalcoholic steatohepatitis

Summary

Background

The progression of the nonalcoholic fatty liver disease to nonalcoholic steatohepatitis (NASH) is multifactorial, and there is still a lack of approved medications for its treatment. The study aimed to evaluate the impact of combined treatment with Pentoxifylline and Metformin on biochemical parameters in patients with NASH. Setting: Outpatient hepatology clinic.

Methods

A prospective trial was conducted. The first cohort included patients with biopsy-proven NASH, while the second cohort consisted of patients with biopsy-confirmed NAFLD. Blood tests were checked at baseline and every three months. Pentoxifylline at a dosage of 400 mg t.i.d. and Metformin at the dosage of 500 mg t.i.d. were introduced for six months in NASH group. The impact of the treatment was assessed based on biochemical results after combined treatment with low-cost medications.

Results

All 33 NASH patients completed 24 weeks of treatment. We observed significant improvement (p<0.05) of median values after treatment for the following parameters: serum uric acid levels decreased by 51.0 micromol/L, calcium decreased for 0.27 mmoL/L, magnesium showed an increase of 0.11 mmoL/L. Insulin resistance improved as a reduction of HOMA – IR by 1.3 was detected. A significant decrease of median in liver enzymes, alanine aminotransferase, aspartate aminotransferase and gammaglutamyltransferase by 24.0 IU/L, 9.1 IU/L, 10.8 IU/L respectively, was noted.

Conclusions

Pentoxifylline and Metformin may provide possible treatment option in NASH. Some new potential benefit of the therapy in improving liver function whilst decreasing cardiovascular risk was perceived.

Open access
Analysis of expression of genes responsible for regulation of cellular proliferation and migration – microarray approach based on porcine oocyte model

Abstract

The formation of mammalian oocytes begins in the ovary during fetal development. The proper development of oocytes requires close communication with surrounding somatic cells, the substances they emit allow proper maturation of oocytes. Somatic cumulus (CC) cells and oocytes form cumulus-oocyte (COC) complexes.

In this study, the Affymetrix microarray analysis was used to investigate changes in gene expression occurring in oocytes before and after in vitro maturation (IVM). The aim of the study was to examine oocyte genes involved in two ontological groups, “regulation of cell migration” and “regulation of cell proliferation” discovered by the microarray method.

We found a reduced expression of all 28 genes tested in the ontological groups: ID2, VEGFA, BTG2, CCND2, EDNRA, TGFBR3, GJA, LAMA2, RTN4, CDK6, IHH, MAGED1, INSR, CD9, PTGES, TXNIP, ITGB1, SMAD4, MAP3K1, NOTCH2 , IGFBP7, KLF10, KIT, TPM1, PLD1, BTG3, CD47 and MITF. We chose the most regulated genes down the IVM culture, and pointed out those belonging to two ontological groups.

Increased expression of the described genes before IVM maturation may indicate the important role of these genes in the process of ovum maturation. After the maturation process, the proteins produced by them did not play such an important role. In summary, the study provides us with many genes that can serve as molecular markers of oocyte processes associated with in vitro maturation. This knowledge can be used for detailed studies on the regulation of oocyte maturation processes.

Running title: Genes regulating cellular migration and proliferation in porcine oocytes

Open access
Differential expression pattern of genes involved in oxygen metabolism in epithelial oviductal cells during primary in vitro culture

Abstract

Oxygen metabolism is crucial in establishing successful pregnancy, since excessive amount of reactive oxygen species (ROS) may exert deleterious effects on the developing embryo. There are several defense mechanisms against oxidative stress in the female reproductive tract, including production of antioxidant enzymes by oviductal epithelial cells (OECs). Undoubtedly, OECs play major part in female fertility and may also serve as an in vitro model of the oviduct. Therefore, the aim of this study was to investigate the expression of genes involved in oxygen metabolism. We have isolated OECs from oviducts of crossbred gilts (n=45) and maintained their in vitro culture for 30 days, collecting their RNA at days 1, 7, 15 and 30. The gene expression was determined with the use of Affymetrix® Porcine Gene 1.1 ST Array Strip. Our results revealed 166 differentially expressed genes belonging to four ontology groups: „cellular response to oxidative stress”, “cellular response to oxygen-containing compound”, “cellular response to oxygen levels” and “cellular response to reactive oxygen species”, most of which are also involved in other major processes in the organism. However, our findings provide a valuable insight into porcine reproductive biology and may be utilized in optimization of assisted reproduction techniques.

Running title: Genes involved in oxygen metabolism in oviductal epithelial cells

Open access
Genes encoding proteins regulating fatty acid metabolism and cellular response to lipids are differentially expressed in porcine luminal epithelium during long-term culture

Abstract

Among many factors, the epithelium lining the oviductal lumenis very important for the development of the oocyte and its subsequent fertilization. The oviductal epithelium is characterized by the presence of ciliary cells, supporting the movement of cumulus-oocyte complexes towards the uterus. By interacting with the semen, the epithelium of the fallopian tube makes the sperm acquire the ability to fertilize. So far, the exact molecular mechanisms of these changes have not been known. Hence, understanding the metabolism of oviduct epithelial cells and the level of expression of individual groups of genes seems to be a way to deepen the knowledge about the broadly understood reproduction.

In our research, we decided to culture oviductal epithelial cells (OECs) in vitro for a long period of time. After 24h, 7, 15 and 30 days, the OECs were harvested, with their RNA isolated. Transcriptomic changes were analyzed using microarrays. The “cellular response to lipid” group was represented by the following genes: MUC1, CYP24A1, KLF4, IL24, SNAI2, CXCL10, PPARD, TNC, ABCA10, while the genes belonging to the “cellular lipid metabolic processes” were: LIPG, ARSK, ACADL, FADS3, P2RX7, ACSS2, PPARD, KITLG, SPTLC3, ERBB3, KLF4, CRABP2. Additionally, PPARD and ACADL were members of the “fatty acid beta-oxidation” ontology group. Our study describes genes that are not directly related to fertility processes. However, significant changes in their expression in in vitro cultured OECs may indicate their usefulness as markers of OECs’ physiological processes.

Running title: Fatty acids changes in porcine oviductal epithelial cells in in vitro cultivation

Open access
Genes regulating biochemical pathways of oxygen metabolism in porcine oviductal epithelial cells during long-term IVC

Abstract

Oxygen metabolism has an important role in the normal functioning of reproductive system, as well as the pathogenesis of female infertility. Oxidative stress seems to be responsible for the initiation or development of reproductive organ diseases, including polycystic ovary syndrome, endometriosis, preeclampsia, etc. Given the important role of maintaining balance between the production of ROS and antioxidant defence in the proper functioning of reproductive system, in the present study we aimed to analyse the expression of genes related to oxygen metabolism in porcine oviductal epithelial cells during long-term in vitro culture. The oviducts were collected from 45 crossbred gilts at the age of approximately nine months that displayed at least two regular oestrous cycles. The oviductal endothelial cells were isolated by enzymatic digestion to establish long-term primary cultures. Gene expression changes between 7, 15 and 30 daysof culturewere analysed with the use ofwhole transcriptome profiling by Affymetrix microarrays. The most of the “cellular response to oxidative stress” genes were upregulated. However, we did not observe any main trend in changes within the “cellular response to oxygen-containing compound” ontology group, where the gene expression levels were changed in various manner.

Running title: Oxygen metabolism in porcine oviductal epithelial cells

Open access
The genes regulating maintenance of cellular protein location are differentially expressed in porcine epithelial oviductal cells during longterm in vitro cultivation

Abstract

The oviduct is a part of female reproductive tract that is essential for successful fertilization and early embryo development. It is lined with epithelium consisting of two types of cells: ciliated and secretory. The primary function of ciliated oviductal epithelial cells (OECs) is to support the transport of gametes and embryos through the ovary, whereas secretory OECs produce components of the oviductal fluid. Undoubtedly, the oviductal epithelium plays a major part in the early aspects of pregnancy development, from providing an optimal environment for gametes and embryos to supporting fertilization. Therefore, our aim was to gain a better insight into the genetic changes underlying function of these cells. We have harvested OECs from crossbred gilts (n=45), at the age of about nine months and which displayed two regular estrous cycles, and established long-term primary culture of porcine OECs. Microarray analysis was utilized to determine differentially expressed genes during day 1, 7, 15 and 30 of cultivation, with our results revealing54 differentially expressed genes belonging to three ontology groups: „maintenance of location”, „maintenance of protein location” and „maintenance of protein location in cell”. Since the biochemistry and morphology of epithelial cells may change during long term cultivation, we conclude that our results are a reflection of these changes and help to shed a light on porcine OECs properties in in vitro environment.

Running title: Maintenance of cellular protein location in porcine epithelial oviductal cells

Open access