Evaluation of the chemopreventive effects of Hypericum perforatum L on DMBA-applied rat oral mucosa.

OBJECTIVE: Hypericum perforatum L also known as St. John's wort is known to have many beneficial properties for the organism including its antioxidant and anticancer activities. It is also known to have shown antiproliferative and cytotoxic effects against various cancer cell lines. The purpose of this study was to investigate the effects of Hypericum perforatum L on 7,12-dimethylbenz(a)anthracene-induced rat oral squamous cell carcinoma model. DESIGN: The in vitro antioxidant properties of Hypericum perforatum L was determined and an extract was prepared. Thirty Wistar male rats were divided randomly into 4 groups (Control group, DMBA group, HP + DMBA group, HP group). The antioxidant defense mechanisms in tissue and blood samples were evaluated biochemically and immunohistochemically, the carcinomatous changes in connective tissue were investigated immunohistochemically and epithelial changes in the tissue samples were evaluated histopathologically. RESULTS: The extract revealed inhibitory effects on some antioxidant enzymes (catalase, glutathione peroxidase). Immunohistochemical evaluations revealed no invasive changes in the connective tissue. Hypericum perforatum L demonstrated chemopreventive effects although it did not prevent carcinomatous changes altogether. CONCLUSIONS: Hypericum perforatum L is a promising chemopreventive agent and further studies are needed in order to evaluate the full potential of this plant.

Evaluation of the pathophysiological role of Fetuin A levels in adolescents with polycystic ovary syndrome.

OBJECTIVES: Polycystic ovary syndrome (PCOS) is an endocrinopathy, in which hyperandrogenism and hyperinsulinism have both occurred. Fetuin-A, a natural inhibitor of tyrosine kinase, leads to insulin resistance. The aim was to evaluate the relationship between fetuin-A and hyperandrogenism and hyperinsulinism and the role of fetuin-A in the pathophysiology of PCOS. METHODS: Thirty-eight cases with PCOS and 40 healthy adolescents were included in the study. PCOS and controls were divided into obese/non-obese subgroups. LH, FSH, total and free testosterone (TT, FT), SHBG, androstenedione, DHEAS were measured in patients with PCOS. Fasting glucose, insulin, lipid profile, AST, ALT, HsCRP, and fetuin levels of PCOS patients and healthy controls were also measured. RESULTS: Fetuin-A levels were higher in PCOS patients than in controls. In the obese-PCOS group, when compared to non-obese PCOS patients; the levels of SHBG and HDL were low while cholesterol, LDL, triglyceride, HOMA-IR, FT, FAI, and HSCRP levels were high, but Fetuin-A levels were similar. In the obese-PCOS group, fetuin-A levels were higher than in obese-controls. HOMA-IR and fetuin-A levels were higher in non-obese PCOS patients than in non-obese controls. In the PCOS group, fetuin-A was positively correlated with TT, FT, FAI and androstenedione and negatively correlated with SHBG. Regression analysis demonstrated that FT, SHBG, and androstenedione significantly predicted fetuin-A levels (R2=54%). In non-obese PCOS patients and controls, fetuin-A was positively correlated with insulin and HOMA-IR. CONCLUSIONS: These results suggest a relationship between androgen levels and fetuin-A in PCOS cases, independent of insulin resistance, and may shed light on further studies.

Serum Fetuin-A and Insulin Levels in Classic Congenital Adrenal Hyperplasia.

Androgens play a pivotal role in non-reproductive organs such as the kidney, heart, liver, and pancreas. As androgen receptors are expressed in pancreatic and liver cells, excess testosterone can result in hypersecretion of insulin and fetuin-A, a protein produced in the liver. The expression of fetuin-A, a natural inhibitor of tyrosine kinase activity in muscle and liver, leads to insulin resistance. In addition, insulin and fetuin-A levels are thought to be affected by drugs such as glucocorticoids (GCs) and fludrocortisone. However, whether fetuin-A and insulin levels are affected by androgens and GCs in patients with classic congenital adrenal hyperplasia (CAH) is unknown. This cross-sectional study included 56 CAH patients and 70 controls. Analyses were stratified by sex and prepubertal/pubertal status to control for potential changes in serum metabolic/inflammatory markers associated with the production of sex steroids. Fasting blood glucose, insulin, triglyceride, total cholesterol, high density lipoprotein-cholesterol, aspartate aminotransferase, alanine aminotransferase, fetuin-A, and high-sensitivity C-reactive protein (hs-CRP) levels were measured in blood samples. In addition, 17α-hydroxyprogesterone, androstenedione, total testosterone, free testosterone, and dehydroepiandrosterone sulfate levels were measured before medication was administered. Insulin and fetuin-A levels were significantly higher in CAH patients than in controls. The unfavourably high levels of these substances exhibited a positive correlation with total and free testosterone. Regression analysis revealed that fetuin-A and free testosterone were the only independent predictors of the insulin level, while insulin and free testosterone levels significantly predicted the fetuin-A level (R2=42.7% and 59.8%). Differences were also observed in triglyceride and hs-CRP levels between the pubertal and prepubertal groups. We conclude that serum fetuin-A and insulin levels may be associated with androgens in CAH patients.

Dipeptidyl peptidase-4 and adenosine deaminase enzyme levels in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies in reproductive age women and insulin resistance (IR) and hyperinsulinism play a critical role in the pathogenesis. Glucagon-like peptide-1 (GLP-1), promotes insulin secretion, inhibits glucagon secretion. GLP-1 is degraded by dipeptidyl peptidase-4 (DPP-4). DPP-4, also interacts with adenosine deaminase (ADA). Therefore, IR may have a significant connection with ADA activity. The aim of this study is to compare levels of DPP-4 and ADA enzymes in PCOS and infertile patients. Forty-four patients with PCOS and 44 infertile patients with normal ovarian reserve were enrolled in the study. Serum ADA, DPP-4, AMH, glucose and insulin levels were measured. HOMA-IR method was used to assess insulin sensitivity. ADA, DPP-4, AMH, HOMA-IR (p < .05) and insulin levels (p < .01) were found to be increased in PCOS patients. Considering all study participants AMH levels were found to be positively correlated with ADA (r: 0.734) and DPP-4 (r: 0.449) levels. Also ADA levels were found to be positively correlated with DPP-4 (r: 0.472), insulin (r: 0.216) and HOMA-IR (r: 0.223). Our findings about the elevation of DPP-4 levels in patients with PCOS suggest that the use of DPP-4 inhibitors may be beneficial in treatment of these patients.

Effects of garlic extract consumption on blood lipid and oxidant/antioxidant parameters in humans with high blood cholesterol.

Effects of garlic extract supplementation on blood lipid profile and oxidant/antioxidant status were investigated in volunteer subjects with high blood cholesterol. A total of 23 volunteer subjects with high blood cholesterol (>5.98 mmol/L) participated in the study. Of them, 13 patients were evaluated as a hypertensive group and the others a normotensive group. Before (first sample) and after (second sample) garlic extract consumption for 4 months, routine blood analyses including lipid parameters and liver and kidney function tests were performed. Additionally, blood oxidant (malondialdehyde [MDA], oxidation resistance [OR]), and antioxidant (antioxidant potential [AOP], nonenzymatic superoxide radical scavenger activity [NSSA]) parameters were measured. Serum total cholesterol, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterols, and triglyceride levels were found to be significantly lowered, but HDL high-density lipoprotein cholesterol level increased after the extract use. The total:HDL cholesterol ratio was also found to be significantly decreased after the extract use. There were no meaningful differences with regard to other routine biochemical parameters. Additionally, blood AOP, OR, and NSSA values were found increased and MDA level decreased in the second samples relative to the first ones. Systolic and diastolic blood pressure values were also found to be significantly lowered after extract supplementation in the hypertensive group, but no similar changes were observed in the normotensive group. We conclude that garlic extract supplementation improves blood lipid profile, strengthens blood antioxidant potential, and causes significant reductions in systolic and diastolic blood pressures. It also leads to a decrease in the level of oxidation product (MDA) in the blood samples, which demonstrates reduced oxidation reactions in the body.

Oxidative stress in patients with chronic renal failure: effects of hemodialysis.

OBJECTIVE: To investigate blood oxidative status of patients with chronic renal failure (CRF) and possible effects of hemodialysis on the development of oxidative stress in blood. MATERIALS AND METHODS: The levels of malondialdehyde (MDA) and oxidation resistance (OR) values were measured in blood plasma, erythrocyte hemolysate and erythrocyte membrane fractions of 33 patients with CRF and of 12 healthy controls. Of the 33 patients, 17 subjects were under hemodialysis treatment. RESULTS: MDA levels were found to be increased in all blood fractions of the patients. OR values were unchanged in erythrocyte hemolysates but decreased in plasma and erythrocyte membrane fractions of the CRF patients. Moreover, erythrocyte MDA levels were determined to be higher in hemodialyzed patients compared with both controls and non-hemodialyzed patients. OR values were lower in all blood fractions of the hemodialyzed patients relative to controls and non-hemodialyzed patients. CONCLUSION: Results suggest that there is a significant oxidative stress (expressed as peroxidation) in blood samples from patients with CRF, which is further exacerbated by hemodialysis.