Direct and indirect effects of kisspeptin on liver oxidant and antioxidant systems in young male rats

Kisspeptin is a recently discovered hypothalamic peptide which plays an important role in the central control of reproductive functions. We have investigated direct and indirect effects of kisspeptin on the liver oxidative stress in young male rats. Twenty‐four rats were divided into four groups (n = 6/group). First group served as control and received saline. Kisspeptin‐10 was administered to the animals in the second group (20 nmol/rat/day), for a period of 7 days. Rats were given only one dose gosereline (0.9 mg/rat), a GnRH agonist in the third group. The last group received kisspeptin‐10 with gosereline. The activities of catalase, superoxide dismutase (SOD), xanthine oxidase (XO), adenosine deaminase (AD) and level of malondialdehyde were studied in liver tissue. Serum samples were separated for total antioxidant capacity (TAC), total oxidant status (TOS), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, blood urea nitrogen (BUN), colesterol, high‐density lipoprotein (HDL) and triglyceride. Kisspeptin increased the activities of SOD and catalase (p < 0.05). When compared to the control group, the levels of malondialdehyde, TOS and AST were lower, but levels of BUN, cholesterole, HDL and AD were higher in the other three groups (p < 0.05). In conclusion, our findings suggest that kisspeptin may have antioxidant and thus protective effects on the liver tissue. Copyright © 2010 John Wiley & Sons, Ltd.     

Plasma Trace Elements, Vitamin B12, Folate, and Homocysteine Levels in Cirrhotic Patients Compared to Healthy Controls

Increased serum homocysteine (Hcy) can induce liver diseases and can play a remarkable role in hepatic disorders. The purpose of the present study therefore was to investigate the relationship between serum vitamin B(12), folate, zinc and copper, cysteine, and Hcy level differences between cirrhotic patients and healthy subjects. We studied 32 cirrhotic patients (12 females and 20 males) aged 45 +/- 11 years and 32 control subjects (12 females and 20 males) aged 39 +/- 9 years. There was an inverse correlation between Hcy and vitamin B(12) in controls (r = -0.442, p < 0.011) but not in cirrhotic patients (r = -0.147, not significant). Also, mean plasma folate was decreased in cirrhotic patients compared to controls (p < 0.001). Copper increased whereas zinc decreased significantly in cirrhotic patients. A positive correlation was seen between the Cu/Zn ratio and Cu in controls (r = 0.690, p < 0.01), but the correlation between the Cu/Zn ratio and Cu was not significant in the cirrhotic group. Negative correlations were seen between plasma concentration of zinc and the Cu/Zn ratio in controls and cirrhotic patients (r = -0.618, p < 0.01 and r = -0.670, p < 0.01, respectively). Cirrhotic patients displayed multiple abnormalities, including changes in cysteine metabolism and in zinc and copper levels. Although hyperhomocysteinemia is known as an atherogenic and thrombogenic risk factor for cardiovascular disease, it might also be a risk factor for cirrhotic patients. Plasma Hcy, vitamin B(12), and folic acid measurement may be useful in the evaluation of cirrhotic patients.     

In vivo and in vitro regulation of Akt activation in human endometrial cells is estrogen dependent

Estrogen-bound estrogen receptors (ER) alpha and beta classically activate gene expression after binding to the estrogen response element in the promoter regions of target genes. Estrogen also has rapid, nongenomic effects. It activates several membranous or cytoplasmic kinase cascades, including the phosphatidylinositol 3-phosphate (PI3K/Akt) cascade, a signaling pathway that plays a key role in cell survival and apoptosis. Normal human endometrium is exposed to variable levels of steroid hormones throughout the menstrual cycle. We hypothesized that Akt phosphorylation in human endometrium may vary with the menstrual cycle and in early pregnancy and that fluctuations in estrogen level may play a role in Akt activation in endometrial cells. We analyzed Akt phosphorylation using in vivo and in vitro techniques, including Western blot, immunohistochemistry, and immunocytochemistry. Estradiol significantly increased Akt phosphorylation in endometrial cells. Rapid stimulation of Akt activation in cultured stromal cells was observed. Akt phosphorylation by estradiol was inhibited by the PI3K inhibitor, wortmannin, but not by the ER antagonist, ICI 182 780. The maximal effect on Akt activity was observed following 5-15 min of estradiol treatment. Our results suggest that estradiol may directly affect PI3K-related signaling pathway by increasing the phosphorylation of Akt in endometrial cells. Thus, estradiol may exert part of its proliferative and antiapoptotic effects by a nongenomic manner through the Akt signaling pathway.     

Zinc and copper status in acute pancreatitis: an experimental study

Metal ions are required as active components of several proteins, including pancreatic enzymes, and they can play important roles in the etiopathogenesis of acute pancreatitis. In the present study, we measured the concentrations of zinc (Zn) and copper (Cu) in both serum and pancreatic tissue, as markers of trace element status in an experimental acute pancreatitis model. Twenty-four male Wistar rats were divided into two groups: the experimental group (N=24) and the control group (N=10). Acute pancreatitis was induced by injection of 48% ethyl alcohol into the common biliary duct. The animals were sacrificed 24 h later to detect the concentrations of Zn and Cu. There was no significant difference in tissue Zn and Cu concentrations between control and experimental groups (p<0.05). However, in the acute pancreatitis group, serum Zn and Culevels were very significantly lower (p<0.001 and p<0.0001, respectively). In conclusuion, these findings suggested that altered mineral metabolism in serum and pancreatic tissue may have contributed to the pathophysiology of acute pancreatitis.     

Col IV and Fn distribution in prostatic adenocarcinoma and correlation of 67LR, MMP-9 and TIMP-1 expression with Gleason score

OBJECTIVE: To assess the immunoreactivity of 5 proteins related to basement membrane (BM) and extracellular matrix in order to investigate whether any of them correlates with differentiation of prostatic adenocarcinoma (PAc). Two of these markers are collagen type IV (Col IV), the collagenous component of basement membrane, and fibronectin (Fn), an adhesion protein in extracellular matrix. Others are matrix metalloproteinase-9 (MMP-9), a type IV collagenase, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), which has a high affinity for MMP-9, and 67-kd laminin receptor (67LR), which belongs to the non-integrin laminin binding receptor family. STUDY DESIGN: Forty-three PAc cases with Gleason scores ranging between 5 and 10 and 10 benign prostatic hyperplasia (BPH) cases, the control group, were included in the study. Formalin-fixed and paraffin-embedded tissue slides from each case were immunostained with the avidin-biotin-peroxidase method. Immunoreactivity was determined by means of a scoring system similar to the Gleason scoring system. RESULTS: Overexpression of Col IV, Fn, 67LR and MMP-9 was detected in PAc as compared with BPH, whereas no difference was determined in TIMP-1 expression. Among these, only 67LR correlated statistically with Gleason score. CONCLUSION: Expression of 67LR in tumor cells was significantly increased in parallel to tumor grade. This may be useful in microscopic evaluation of PAc.     

Effects of dietary chromium chloride supplementation on performance,some serum parameters,and immune response in broilers

This study was conducted to investigate the effect of increasing dietary levels of inorganic chromium (CrCl₃·6H₂O) on the performance, blood chemistry, and immune response of broilers. Eighty newly hatched Ross PM3 broiler chicks were evenly distributed to five groups of 16 chicks each. Two groups (control and only sheep red blood cell inoculated) were fed the basal diet containing 2.2 and 4.5 mg Cr/kg and the remaining groups were fed 20, 40, or 80 mg/kg Cr-supplemented diets for 44 d. Chicks in all groups, except in the control, at 3 and 5 wk of age, were injected intraperitonally with sheep red blood cell for determining the primary and secondary antibody responses, respectively. When the chicks were 4 wk of age, a delayed-type hypersensitivity test was performed. White blood cells were differentiated. Blood samples were collected for the determination of serum proteins, glucose, cholesterol, cortisol, minerals, and alkaline phosphatase activity and for antibody response. Chromium had no effect on weight gain, but 20 mg/kg supplemental Cr resulted in 18.57% reduction in feed consumption and improved feed efficiency by 16.77%. Chromium did not affect serum cholesterol and P levels but reduced serum glucose and increased serum protein, Cr, Ca, and Mg levels, and ALP activity. A slight reduction was observed with Cr supplementation in cortisol levels. Slight but not significant increases were observed with Cr in serum Zn and Cu. Chromium increased the ratio of bursa of Fabricius and liver to body weight. Heterophil and monocyte counts and heterophil/lymphocyte ratio were reduced and lymphocyte counts, total antibody, IgG, and IgM titers were increased by supplemental Cr. All levels of Cr increased the cell-mediated response to phytohemagglutinin. No alterations in tissues were observed by histopathological examinations.     

Insulin-like growth factor-I and insulin-like growth factor binding protein-3 levels of children living in an iodine- and selenium-deficient endemic goiter area

Serum insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) levels were investigated in 31 children living in an endemic goiter area and 33 healthy subjects living in an nonendemic area. Serum IGF-I and IGFBP-3 levels of iodine- and selenium-deficient children were found to be lower than those of control subjects (p<0.001). There was a positive correlation between the IGF-I with chronological age and body mass index. There was also positive correlation between the IGF-I and IGFBP-3. No significant difference was found between the goitrous and nongoitrous children. These results suggest that IGF-I and IGFBP-3 levels are affected by thyroid dysfunction as a result of iodine and selenium deficiency. However, IGF-I and IGFBP-3 levels are not associated with goiter.     

Assessment of DNA damage in women using oral contraceptives

The effect of the use of an oral contraceptive (OC) on the frequency of sister chromatid exchanges (SCEs) and on the response in the alkaline comet assay (single-cell gel electrophoresis (SCGE)) was investigated in 18 women taking contraceptive pills daily for 24 months. As controls, fertile women were included with regular menstrual cycles who received no OC drugs. A significant increase in the number of lymphocytes with DNA migration and an increased frequency of SCE per metaphase were observed in OC users as compared with their age-matched untreated controls (P<0.005). As higher incidences of spontaneous SCEs in peripheral blood lymphocytes have been reported to occur in females during pregnancy due to profound changes in the levels of certain sex hormones such as progesterone and estrogen, particularly during the last trimester, 17 pregnant women served as positive controls in this study in order to test the rate of genetic damage due to those changes. Higher frequencies of SCEs and comet responses were observed in pregnant women than in their matched controls. However, no statistically significant difference in DNA damage was observed between OC users and pregnant women (P>0.05). This study underscores the fact that prolonged and extensive use of these drugs in our daily life may be hazardous and also, that OC users should be aware of multifactorial risk factors (environmental, genetic and life style patterns) that may be responsible for additional DNA damage.     

Chromosomal aberrations under basal conditions and after treatment with X-ray in human lymphocytes as related to the GSTM1 genotype

The frequency of chromosomal aberrations (CAs) was evaluated in blood lymphocytes from 18 healthy subjects. Basal CA frequencies were not significantly different in GSTM1 positive and GSTM1 null subjects (P>0.05), whereas they were considerably higher in smokers than in non-smokers. After 1 Gy dose of X-ray challenge of blood samples, CA frequencies were significantly higher in GSTM1 null subjects, compared to GSTM1 positive subjects (P<0.005), and in smokers, compared to non-smokers. These effects are ascribed to the influence of GSTM1 genotype and of smoking status on DNA repair capacities. As the induction of CAs are associated with carcinogenesis, the challenge assay is able to detect enhanced susceptibility for CA caused by genetic predisposition of DNA repair deficiency.