Genetics of Cd36 and the clustering of multiple cardiovascular risk factors in spontaneous hypertension

Disorders of carbohydrate and lipid metabolism have been reported to cluster in patients with essential hypertension and in spontaneously hypertensive rats (SHRs). A deletion in the Cd36 gene on chromosome 4 has recently been implicated in defective carbohydrate and lipid metabolism in isolated adipocytes from SHRs. However, the role of Cd36 and chromosome 4 in the control of blood pressure and systemic cardiovascular risk factors in SHRs is unknown. In the SHR. BN-Il6/Npy congenic strain, we have found that transfer of a segment of chromosome 4 (including Cd36) from the Brown Norway (BN) rat onto the SHR background induces reductions in blood pressure and ameliorates dietary-induced glucose intolerance, hyperinsulinemia, and hypertriglyceridemia. These results demonstrate that a single chromosome region can influence a broad spectrum of cardiovascular risk factors involved in the hypertension metabolic syndrome. However, analysis of Cd36 genotypes in the SHR and stroke-prone SHR strains indicates that the deletion variant of Cd36 was not critical to the initial selection for hypertension in the SHR model. Thus, the ability of chromosome 4 to influence multiple cardiovascular risk factors, including hypertension, may depend on linkage of Cd36 to other genes trapped within the differential segment of the SHR. BN-Il6/Npy strain.     

THE PERIPHERAL BLOOD LEUKOCYTE PHENOTYPE IN PATIENTS WITH BREAST CANCER: EFFECT OF DOXORUBICIN/PACLITAXEL COMBINATION CHEMOTHERAPY

Presence of functional immune system is critical for any attempt aimed at improving survival of breast cancer patients by strategies based on immune system manipulation. We evaluated by flow cytometry the phenotype of peripheral blood leukocyte of 43 breast cancer patients. In 11 patients, the phenotype was evaluated before and during the chemotherapy by combination of doxorubicin and paclitaxel (AT). Compared with controls breast cancer patients had significantly higher relative and absolute numbers of CD3^-HLADR⁺, CD3^-CD69⁺ and CD14⁺CD16^-, and significantly lower percentages of CD3^- and CD8^-CD28⁺ cells. After one cycle of AT, the absolute numbers of CD3⁺, CD3^-CD4^-, CD3⁺CD8⁺ and CD8^-CD28⁺ cells increased significantly. Present data show a presence of T-cell activation in breast cancer patients. Administration of AT may lead to an increase in functional T-cells in peripheral blood, indicating a potential for combining chemotherapy with immunotherapy in the treatment of breast cancer patients.     

Loss of TP53 expression in immortalized choroid plexus epithelial cells results in increased resistance to anticancer agents

Choroid plexus carcinomas are malignant brain tumors predominantly arising in young children. Because a prognostic role of p53 alterations has been demonstrated, further research into potential underlying mechanisms is essential. Our objective was, therefore, to investigate the role of p53 in the growth-inhibitory potential of a variety of anticancer agents in the rodent choroid plexus epithelial cell line Z310. Furthermore, association of p53 alterations with proliferative activity (Ki67/MIB1) in choroid plexus carcinoma samples (N?=?20) was examined by use of immunohistochemistry. Silencing of TP53 expression did not significantly alter metabolic activity in Z310 cells and p53 protein expression status was not associated with increased proliferative activity in choroid plexus carcinomas. However, the growth-inhibitory activity of vincristine, doxorubicin, carboplatin, etoposide, and temozolomide was significantly impaired by silencing of TP53. In conclusion, these results indicate a potential predictive role of p53 in choroid plexus carcinomas. Alterations of p53 should be taken into account when evaluating the effect of anticancer agents in future clinical trials.     

Adipose tissue-derived human mesenchymal stem cells mediated prodrug cancer gene therapy

Human adipose tissue-derived mesenchymal stem cells (AT-MSC) are considered to be a promising source of autologous stem cells in personalized cell-based therapies. Tumor tracking properties of MSC provide an attractive opportunity for targeted transgene delivery into the sites of tumor formation. In the present study, we addressed whether the suicide gene introduction into human AT-MSC could produce a tumor-specific prodrug converting cellular vehicle for targeted chemotherapy. We prepared yeast fusion cytosine deaminase::uracil phosphoribosyltransferase gene-expressing cells [cytosine deaminase (CD)-expressing AT-MSC (CD-AT-MSC)] by retrovirus transduction. We explored their therapeutic potential on a model of human colon cancer in the presence of prodrug 5-fluorocytosine (5-FC). Gene manipulation of human AT-MSC did not sensitize CD-AT-MSC to 5-FC, thus overcoming the inherent disadvantage of suicide effect on cellular vehicle. CD-AT-MSC in combination with 5-FC augmented the bystander effect and selective cytotoxicity on target tumor cells HT-29 in direct coculture in vitro. We confirmed directed migration ability of AT-MSC and CD-AT-MSC toward tumor cells HT-29 in vitro. Moreover, we achieved significant inhibition of s.c. tumor xenograft growth by s.c. or i.v. administered CD-AT-MSC in immunocompromised mice treated with 5-FC. We confirmed the ability of CD-AT-MSC to deliver the CD transgene to the site of tumor formation and mediate strong antitumor effect in vivo. Taken together, these data characterize MSC derived from adipose tissue as suitable delivery vehicles for prodrug converting gene and show their utility for a personalized cell-based targeted cancer gene therapy.     

1H NMR metabolomics analysis of renal cell carcinoma cells: Effect of VHL inactivation on metabolism

Von Hippel‐Lindau (VHL) is an onco‐suppressor involved in oxygen and energy‐dependent promotion of protein ubiquitination and proteosomal degradation. Loss of function mutations of VHL (VHL‐cells) result in organ specific cancers with the best studied example in renal cell carcinomas. VHL has a well‐established role in deactivation of hypoxia‐inducible factor (HIF‐1) and in regulation of PI3K/AKT/mTOR activity. Cell culture metabolomics analysis was utilized to determined effect of VHL and HIF‐1α or HIF‐2α on metabolism of renal cell carcinomas (RCC). RCC cells were stably transfected with VHL or shRNA designed to silence HIF‐1α or HIF‐2α genes. Obtained metabolic data was analysed qualitatively, searching for overall effects on metabolism as well as quantitatively, using methods developed in our group in order to determine specific metabolic changes. Analysis of the effect of VHL and HIF silencing on cellular metabolic footprints and fingerprints provided information about the metabolic pathways affected by VHL through HIF function as well as independently of HIF. Through correlation network analysis as well as statistical analysis of significant metabolic changes we have determined effects of VHL and HIF on energy production, amino acid metabolism, choline metabolism as well as cell regulation and signaling. VHL was shown to influence cellular metabolism through its effect on HIF proteins as well as by affecting activity of other factors.     

Weekly variation of hospital admissions for stroke in Nis (Serbia)

Objectives

Weekly variability in stroke occurrence could be related to the change in behaviors of patients or medical personnel that occur during certain periods of the week. The aim of the present study was to examine the weekly variation in hospital admissions for stroke in Nis (Serbia), as well as to investigate how the demographic factors influenced these changes.

Patients and methods

The main data source for this study was the Nis Stroke Registry. During the study period (1996–2007) a total of 9675 stroke patients were registered. According to stroke subtypes, all registered patients were divided into three groups: patients with subarachnoid hemorrhage (SAH) (438 or 4.5%), patients with intracerebral hemorrhage (ICH) (1576 or 16.3%) and patients with ischemic stroke (IS) (6946 or 71.8%). Analyses were conducted separately for SAH, ICH and IS. Each stroke type was stratified by gender, age group and education level.

Results

We have showed that there is a significant weekly variability in the number of SAH (p = 0.028) and IS (p < 0.001) admissions, with the minimum number of admissions on Sundays (39.27 and 14.04% less than expected), and the maximum one on Tuesdays (21.46% more than expected) and Wednesdays (10.96% more than expected), respectively. We have also registered more SAH (p = 0.015) and IS (p < 0.001) admissions on weekdays than on weekend days.

Conclusion

Results of this hospital-based study confirm that there is a pattern in the variation of the number of stroke admissions on the weekly level. Reasons for the weekly variation of hospital admissions for stroke cannot be determined from the present study.     

Distribution of normal and pathological OGTTs among pregnant population and non-pregnant women with PCOS – the cross-sectional study

Both pregnancy, as physiological, and polycystic ovary syndrome (PCOS), as a pathological condition, carry the risk for developing glucose metabolism abnormalities. In this retrospective cross-sectional study, we hypothesized that pregnancy as a physiological condition carries a higher likelihood for abnormal oral glucose tolerance test (OGTT) results than PCOS as a pathological condition.We have compared the prevalence and likelihood ratios for abnormal OGTT results between non-pregnant women with PCOS (Group A) and pregnant women at 24 to 28 weeks of gestation (Group B). Participants of both study groups underwent glucose tolerance testing with 75 g glucose OGTT. During the study period, 7411 women were tested, 3932 women encompassed Group A, and 3479 women comprised Group B.The numbers of yearly tested pregnant women and the corresponding proportion of tested women among all study participants have decreased during the study period, from 766 to 131 and 89.1% to 20.5%, respectively. Group A had a significantly lower prevalence (4.4%) of pathological OGTT results compared to Group B (8.1%). This has resulted in a 45.427 likelihood ratio (P < .001) for abnormal OGTT results in pregnant women compared to non-pregnant women with PCOS.We might conclude that pregnancy could have a more challenging influence on glucose metabolism and that carries higher risks for abnormal glucose metabolism than PCOS. The awareness of obstetricians regarding physiological changes during pregnancy that predisposes abnormal glucose metabolism is decreasing over time and the compliance concerning OGTT testing of pregnant women is decreasing too.     

Cyanobacteria Microcystis aeruginosa Contributes to the Severity of Fish Diseases: A Study on Spring Viraemia of Carp

Fish are exposed to numerous stressors in the environment including pollution, bacterial and viral agents, and toxic substances. Our study with common carps leveraged an integrated approach (i.e., histology, biochemical and hematological measurements, and analytical chemistry) to understand how cyanobacteria interfere with the impact of a model viral agent, Carp sprivivirus (SVCV), on fish. In addition to the specific effects of a single stressor (SVCV or cyanobacteria), the combination of both stressors worsens markers related to the immune system and liver health. Solely combined exposure resulted in the rise in the production of immunoglobulins, changes in glucose and cholesterol levels, and an elevated marker of impaired liver, alanine aminotransferase (ALT). Analytical determination of the cyanobacterial toxin microcystin-LR (MC-LR) and its structurally similar congener MC-RR and their conjugates showed that SVCV affects neither the levels of MC in the liver nor the detoxification capacity of the liver. MC-LR and MC-RR were depurated from liver mostly in the form of cysteine conjugates (MC-LR-Cys, MC-RR-Cys) in comparison to glutathione conjugates (LR-GSH, RR-GSH). Our study brought new evidence that cyanobacteria worsen the effect of viral agents. Such inclusion of multiple stressor concept helps us to understand how and to what extent the relevant environmental stressors co-influence the health of the fish population.