Magnesium yields opposite effects on the nuclear and cytosolic cascades of apoptosis in different rat brain regions.

OBJECTIVE: Magnesium is considered as potential neuroprotective and therapeutic agent, but certain studies have provided evidence of its apoptotic effectiveness in neurons. We aimed to evaluate the possible apoptotic effects of long-term magnesium use in healthy adult rat brains. MATERIALS AND METHODS: Magnesium citrate and magnesium glycinate compounds were administered orally to rats for 8 weeks (36 mg/kg). Expression levels of Bcl-2, Bax and Cyt-C genes were analyzed by real-time polymerase chain reactions (RT-PCR) in the prefrontal cortex, hippocampus and striatum regions. Bcl-2, Bax and CytC protein levels were measured using ELISA kits. Tissue sections were evaluated histopathologically with hematoxylin-eosin staining. RESULTS: Compared to the control group, the magnesium-administered groups indicated gene expression reductions in almost all brain regions; pro-apoptotic Bax, anti-apoptotic Bcl-2 and Cyt-C gene expression levels were reduced. With magnesium, the Bcl-2 and Bax protein levels were increased. Bax/Bcl-2 gene and protein ratio were also increased in the striatum and hippocampus, whereas Cyt-C protein levels were decreased or did not change in the magnesium treated groups. There was no pathological finding in histological evaluation. CONCLUSIONS: Long-term magnesium usage can promote apoptotic cascade in brain tissue by increasing Bax/Bcl-2 ratio. Cyt-C, a prominent factor processing caspase pathway, was decreased or unchanged. In addition, taking into account the histological evaluation, we supposed that the absence of Cyt-C in the cytosol can prevent the subsequent apoptotic pathway. Consequently, we obtained the findings of apoptotic initiation with magnesium in brain, but this cascade seems to be arrested at later stages.

Association Between Vitamin D Receptor Polymorphism and Familial Mediterranean Fever Disease in Turkish Children.

Familial Mediterranean fever (FMF) is an autosomal recessive, inherited autoinflammatory disease characterized by recurrent, self-limited attacks of fever, and inflammation of serosal surfaces. The aim of our study was to determine a possible relationship between Vitamin D receptor (VDR) gene polymorphisms and the risk of children with FMF. We investigated VDR FokI (rs10735810), TaqI (rs731236), BsmI (rs1544410), and ApaI (rs7975232) polymorphisms in 50 children with FMF and 150 age-matched healthy control subjects. This study was performed by polymerase chain reaction-based restriction fragment length polymorphism. There was no significant difference between patients and controls for VDR FokI, TaqI, BsmI, and ApaI genotypes and alleles (p > 0.05). Results need to be supported by further investigations that define haplotype patterns for VDR gene polymorphisms in a larger group and different ethnic groups of FMF patients.

A novel angiogenesis inhibitor bevacizumab induces apoptosis in the rat endometriosis model.

Our aim was to investigate the effects of anti-vascular endothelial growth factor (anti-VEGF) antibody Bevacizumab on endometrial explants and on apoptotic gene expression levels in the rat endometriosis model. Endometriotic implants were surgically formed, and rats treated with (i) 1 mg/kg single subcutaneous injection of depot leuprolide acetate; (ii) 2.5 mg/kg of single intaperitoneal injection of bevacizumab; (iii) intraperitoneal injection of saline. Histopathologic scores and adhesion scores of endometriotic foci and levels of Bcl-2-associated X protein (Bax), Cytochrome c (Cyt-c), B-cell lymphoma/leukemia 2 (Bcl-2) and B-cell lymphoma-extra large (Bcl-xl) mRNA gene expressions of endometriotic foci. Bevacizumab treatment decreased the endometriotic explant size compared with control. Bevacizumab-treated rats had lower total adhesion scores when compared with the control group. Semi-quantitative evaluation of the persistence of endometrial epithelial cells in the explants showed a lower score in gonadotropin-releasing hormone (GnRH) agonist-treated rats compared with control rats. In Bevacizumab increased expression of Bax 3.1-fold, Cyt-c 1.3-fold and decreased expression of Bcl-2 0.4-fold, Bcl-xl 0.8-fold compared with the control group. The GnRH agonist increased expression of Bax 3.0 fold, Cyt-c 1.3 fold and decreased expression of Bcl-2 0.4-fold, Bcl-xl 0.8-fold, compared with the control group. This study suggests that a novel angiogenesis inhibitor, anti-VEGF antibody bevacizumab is as effective as GnRH agonist in the regression of the endometriotic lesions in rat endometriosis model. One possible mechanism of this effect is the induction of apoptosis.

Vitamin D receptor gene polymorphisms and male breast cancer risk in Turkish population.

PURPOSE: Male breast cancer (MBC) is a rare disease. However, as global populace ages, there is a trend for MBC increase. Although its etiology is still unclear, constitutional, environmental, hormonal (abnormalities in estrogen/androgen balance) and genetic (positive family history, Klinefelter syndrome, mutations in BRCA1 and BRCA2) risk factors are already known. One potential target is the vitamin D receptor (VDR). We have investigated whether polymorphisms in the VDR gene are associated with altered MBC risk in a Turkish population. METHODS: We recruited 25 men with known breast cancer and 96 men selected from blood donations. Polymorphic sites in VDR gene ApaI (rs7975232), TaqI (rs731236) and FokI (rs10735810) were determined by polymerase chain reaction-restriction fragment length polymorphism (PCRRFLP) analysis. RESULTS: The unconditional logistic regression analysis demonstrated no significant association for the VDR ApaI (p=0.70), TaqI polymorphism (p=0.88) and FokI polymorphism (p=0.075). CONCLUSION: Our results do not support potential effects of VDR polymorphisms on MBC risk and possible differential effects of receptor status of the tumor. However, further studies focusing on the influence of polymorphisms and haplotypes on VDR functionality, activity and concentration are needed.

beta-catenin gene mutation in invasive ductal breast cancer.

PURPOSE: Aberrant accumulation of beta-catenin plays an important role in a variety of human neoplasms. In this study we analyzed the somatic mutations of the beta-catenin gene and the immunohistochemical localization of beta-catenin and cyclin D1 in invasive ductal breast cancer. MATERIALS AND METHODS: We investigated 65 human invasive ductal breast cancer samples for somatic mutations in the exons 3, 4, 5 and 6 of beta-catenin gene (N-terminal region) by the combined use of polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP) and sequencing. Sample tissues were also analyzed using beta-catenin and cyclin D1 immunocytochemistry staining. RESULTS: No beta-catenin mutation was detected in any of the tumor samples. Accumulation of aberrant beta-catenin protein in cellular compartments in the same breast cancer samples was confirmed with a related experiment by immunocytochemical methods. CONCLUSION: Our results suggest that genetic defects in beta-catenin is not common in invasive ductal breast cancers, whereas mutations in other components of the Wnt signaling pathway should be considered.

Ischemic preconditioning attenuates the lipid peroxidation and remote lung injury in the rat model of unilateral lower limb ischemia reperfusion.

BACKGROUND: Ischemia and reperfusion of the skeletal muscle tissue may cause remote lung injury. We aimed to evaluate the protective effect of ischemic preconditioning (IP) on the lung during unilateral lower limb ischemia reperfusion (IR). METHODS: Four groups of rats were used in this study: (i) the sham group (sham, n = 6) served as time controls, they remained anesthetized for the whole duration of the study; (ii) the ischemia and reperfusion group (IR, n = 10) underwent 4 h of left lower limb ischemia followed by 2 h of reperfusion; (iii) the ischemic preconditioning group (IP, n = 10), the left lower limbs of rats were exposed to three cycles of IP (10 min of ischemia followed by 10 min of reperfusion); and (iv) the ischemic preconditioning plus ischemia reperfusion group (IP/IR, n = 10) underwent IP followed by IR as in the IP and IR groups. Plasma and tissue samples were taken at the end of the study period for determination of lung tissue myeloperoxidase activity (MPO) and polymorphonuclear leukocyte count (PMNL), histological lung injury score and plasma thiobarbituric acid reactive substances (TBARS) level. RESULTS: PMNL count and MPO activity in the lung tissue, and plasma TBARS level were higher in the IR group compared with other groups while there were no differences between the sham and the IP and between the sham and the IP/IR groups. Histological lung injury score was higher in the IR group than in the IP/IR and sham groups. The plasma TBARS level in the IP group was significantly lower than in the IP/IR group. CONCLUSION: IP pretreatment reduces lipid peroxidation and lung injury caused by lower limb IR.

Consistent loss of heterozygosity at 14Q32 in lymphoid blast crisis of chronic myeloid leukemia.

Little is understood about the basic biological mechanisms that underlie the reasons for acute transformation in chronic myeloid leukemia (CML). Progression of disease may include inactivation of one or more tumor suppressor genes (TSGs). A widely used methodology for indirectly detecting somatic inactivation of TSGs is searching loss of heterozygosity (LOH) for polymorphic loci located in or near the gene(s) of interest. We aimed to analyze DNA of chronic phase and blastic phase archive material of 15 CML patients for LOH using D1S430, D2S123, D3S1611, D11S29, D14S65, D17S520, BAT 40 markers, the dinucleotide repeat located in the ABL gene and the trinucleotide repeat located in the BCR gene (amplification of the trinucleotide in the BCR gene could not be succeeded). LOH was identified by a %50 lost of one of the alleles intensity. LOH was detected with the ABL dinucleotide repeat and D2S123 marker in two patients and with the D14S65 marker in three patients. The three patients exhibiting LOH at the D14S65 locus, all proceeded through lymphoid blast crisis. The D14S65 marker is located at the 14q32 locus which contains the immunoglobulin heavy chain gene and the TCL1 oncogene. 14q32 abnormalities at the molecular level, may be predictive for lymphoid blast crisis, whether or not they are detectable cytogenetically.

Full-length cDNA sequence and genomic organization of human NKX3A - alternative forms and regulation by both androgens and estrogens.

NKX3A (NKX3.1) is a recently identified androgen-regulated gene that is largely specific to prostate for expression and likely to code for a homeobox protein. Here we report the full-length mRNA and genomic organization of human NKX3.1. There are at least five different splice variants of NKX3.1 mRNA that result in different open reading frames (ORFs). There is extensive similarity between the human and the mouse NKX3.1 cDNA sequences outside of the ORFs (greater than 60% overall identity), which may be involved in modulating NKX3.1 expression. In addition to its androgen regulation in the prostate cancer cell line LNCaP, we show that NKX3.1 expression is androgen-dependent in the CWR22 prostate cancer xenograft model. Interestingly, NKX3.1 is highly expressed in the androgen-independent derivative CWR22R in the absence of androgens, indicating that it may be deregulated in advanced prostate cancer. Using a Green Fluorescent Protein fusion construct, we show that NKX3.1 is a nuclear protein consistent with its proposed function as a homeobox transcription factor. Furthermore, in addition to androgens, NKX3.1 expression is up-regulated by 17beta-estradiol, but not by progesterone, dexamethasone, or 3,5,3'-triiodothyronine in LNCaP cells. Regulation of NKX3.1 by androgens and 17beta-estradiol in prostate cancer cells and its deregulation in androgen-independent prostate cancer suggest that it may have important regulatory roles during prostate cancer progression.