Knowledge and awareness about osteoporosis and its related factors among rural Turkish women.

The aim of this study is to evaluate the awareness, perception, sources of information, and knowledge of osteoporosis in a sample of rural Turkish women, to examine the factors related to their knowledge, and organize effective education programs. A total of 768 women mean age 53.6 +/- 8.2 (40-70) were randomly selected and interviewed during their visits to primary care centers in three rural towns in West Anatolia. A structured questionnaire was administered by trained nurses. Chi-squared test was performed in age and educational level groups for revealing factors influencing the awareness, perception, and knowledge sources of osteoporosis. One-way analysis of variance (ANOVA) analysis was carried out in calculating the difference of knowledge scores among groups. Of the women, 60.8% had heard of and 44.9% had the correct definition for osteoporosis. Awareness and accurate definition of osteoporosis was high in younger and high educated women (p < 0.001). Television was the main source of knowledge with the rate of 55%, doctors and nurses/midwives were the second and third sources, respectively. Osteoporosis knowledge was low with a mean score of 5.52 out of 20. Younger and more educated women had higher knowledge scores. Low calcium in diet and menopause were the first two risk factors chosen for osteoporosis. Knowledge about osteoporosis among rural Turkish women is low, and majority of women are unaware of the risk factors and consequences of osteoporosis. Therefore, appropriate educational programs should be planned according to community needs, and the target of these programs should be less educated and older women.

TSH influences serum leptin levels independent of thyroid hormones in hypothyroid and hyperthyroid patients.

Leptin is considered to play a role in maintenance of energy balance and body weight by neuroendocrine mechanisms. The physiological mechanisms for thyroid hormone-induced alteration in serum leptin are not well known. In the present study, the relationship between thyroid hormones and leptin levels was investigated in patients with overt hypothyroidism and hyperthyroidism before and after successful treatment. Leptin levels were determined by radioimmunoassay and body mass index (BMI) was calculated for each subject. Serum leptin levels of 26 hypothyroid and 22 hyperthyroid patients were compared with those of 20 healthy volunteers who comprised the controls. Serum leptin levels of hypothyroid patients (28.4 +/- 4.1 ng/ml) were found to be significantly higher than the controls (19.1 +/- 3.2 ng/ml) (p<0.01), whereas hyperthyroid patients had lower levels (10.7 +/- 1.2 ng/ml) (p<0.01). In hypothyroid patients, serum leptin levels were decreased significantly to 20.6 +/- 2.1 ng/ml with thyroxin treatment (p<0.05). However, in hyperthyroid group, serum leptin levels were increased to 12.4 +/- 2.2 ng/ml by treatment (p>0.05). BMI was not changed with the treatment in either group. The serum leptin levels were correlated with BMI and thyrotropin (TSH) in both hypothyroid and hyperthyroid patients. Serum leptin levels are affected in thyroid disorders and the correlation of leptin with TSH is independent of thyroid hormones.

Beta-cell secretory dysfunction in the pathogenesis of low birth weight-associated diabetes: a murine model.

Low birth weight (LBW) is an important risk factor for type 2 diabetes. We have developed a mouse model of LBW resulting from undernutrition during pregnancy. Restriction of maternal food intake from day 12.5 to 18.5 of pregnancy results in a 23% decrease in birth weight (P < 0.001), with normalization after birth. However, offspring of undernutrition pregnancies develop progressive, severe glucose intolerance by 6 months. To identify early defects that are responsible for this phenotype, we analyzed mice of undernutrition pregnancies at age 2 months, before the onset of glucose intolerance. Fed insulin levels were 1.7-fold higher in mice of undernutrition pregnancies (P = 0.01 vs. controls). However, insulin sensitivity was normal in mice of undernutrition pregnancies, with normal insulin tolerance, insulin-stimulated glucose disposal, and isolated muscle and adipose glucose uptake. Although insulin clearance was mildly impaired in mice of undernutrition pregnancies, the major metabolic phenotype in young mice of undernutrition pregnancies was dysregulation of insulin secretion. Despite normal beta-cell mass, islets from normoglycemic mice of undernutrition pregnancies showed basal hypersecretion of insulin, complete lack of responsiveness to glucose, and a 2.5-fold increase in hexokinase activity. Taken together, these data suggest that, at least in mice, primary beta-cell dysfunction may play a significant role in the pathogenesis of LBW-associated type 2 diabetes.

Effect of thyroid function on LDL oxidation in hypothyroidism and hyperthyroidism.

Oxidized low-density lipoproteins (LDL) are highly suspected of initiating the atherosclerosis process. Hypothyroidism is frequently associated with hypercholesterolemia and carries increased risk for atherosclerosis. In contrast to hypothyroidism, hyperthyroidism is not associated with increased LDL cholesterol, but is associated with increased oxidized LDL. This study was designed to evaluate the changes in LDL oxidation in subjects with hypothyroidism or hyperthyroidism, and to reveal the effects of treatment in hypothyroidism and hyperthyroidism on LDL oxidation and lipid profiles. Thirty-two patients with hypothyroidism and 16 patients with hyperthyroidism were studied before the therapy and thereafter, when they were euthyroid with appropriate treatment. Plasma lipids and lipoproteins, and the oxidizability of LDL by determining the levels of malonaldehyde bis (dimethyacetyl) (MDA) and diene conjugation, were determined at baseline and after the patients were rendered euthyroid. The actual content of dienes in LDL particles was increased in hypothyroidism, with a decrease after T4 supplementation (p < .001). Dienes in LDL particles were increased in hyperthyroidism, with a decrease after treatment (p < .05). In hypothyroid patients, the lag phase was shorter in the pretreatment period than in the euthyroid period (p > .05). The lag phase of hyperthyroid patients was shorter in the pretreatment period than in the euthyroid period and hypothyroid state (p < .001). The Cu2+-catalyzed dienes of LDL and MDA oxidation in the hypothyroid state and the subsequent euthyroid states were decreased (p < .001). The Cu2+-catalyzed dienes of LDL (p < .01) and MDA oxidation (p < .001) in hyperthyroid patients after treatment were decreased. The enhanced LDL oxidation may play a role in the cardiac disease process in both hypothyroidism and hyperthyroidism.

The effects of estrogen and raloxifene treatment on antioxidant enzymes in brain and liver of ovarectomized female rats.

Recent studies documented that estrogen have antioxidant properties in-vitro, there are conflicting results on the effect of estrogen in vivo. We aimed to investigate the effects of estradiol and Raloxifene on the antioxidant enzyme [superoxide dismutase (SOD) and catalase (CAT)] activities and MDA levels in brain and liver homogenates of ovariectomized female rats. Twelve weeks after ovariectomy, female Sprague-Dawley rats (n = 26) were divided into three groups: (1) Ovariectomized placebo group (n = 6) was given physiologic saline. (2) Estrogen group (n = 10) was given Ethynyl estradiol, 0.1 mg/kg sc. (3) Raloxifene group (n = 10) was given raloxifene, 1 mg/kg sc during 8 weeks. Ten rats were used as naive controls without any treatment (Sham operated group, n = 10). Ovariectomy lead to an increase in the CAT activities in liver tissue samples compared to the sham group (p = 0.056, Mann-Whitney test). While estrogen treatment reversed to normal levels of CAT activities, raloxifene remained as ineffective. Superoxide dismutase activities and MDA levels in liver were remained unchanged in all groups. There was no significant change in the brain tissue SOD and CAT activities between the control ovariectomy, estrogen treated, and raloxifen treated groups. We determined an increase in MDA levels in brain of ovariectmised rat (p = 0.02). While raloxifene treatment reversed to normal levels of MDA (p = estrogen treatment failed. Our data showed that estrogen may play a role in regulation of CAT and SOD activities in liver due to its antioxidative effects. We can suggest estrogen and raloxifene exert their antioxidative effects in brain rather than liver. Since Raloxifene's effect is more clear than estradiol, raloxifene may be suggested primarily for treatment and/or prevention of diseases which can be resulted from oxidative stress in postmenopausal women.

The effects of estrogen and raloxifene treatment on the antioxidant enzymes and nitrite-nitrate levels in brain cortex of ovariectomized rats.

Number of studies indicate that the female gonadal hormone estrogen protects women against several neurodegenerative diseases and cerebral ischemia via various mechanisms. The possible protective effects of estrogen are mediated mainly by three ways; the activation of steroid receptors and/or modulation of a neurotransmitter and/or direct antioxidative action. Therefore we aimed to investigate the effects of estradiol and raloxifene on levels of nitric oxide (NO) and antioxidant enzymes in brain cortex of ovariectomized female rats. Ten Sprague-Dawley rats were used as naive controls while 32 rats were ovariectomized at 120-140 days of age. Twelve weeks after ovariectomy: (1). Ovariectomized Placebo group (n=11), was given physiologic saline. (2). Estrogen group (n=10) was given Ethynyl estradiol, 0.1 mg/kg sc. (3). Raloxifene group (n=10) was given raloxifene, 1 mg/kg sc. At the end of the treatment period (8 weeks), rats were decapitated and cortex samples were dissected. Results showed that ovariectomy caused a decrease in total nitrite-nitrate levels. The NO levels of both the estrogen and the raloxifene group were higher than the placebo group. Catalase activities did not show any significant difference between the groups, while superoxide dismutase (SOD) activities were elevated via ovariectomy. Estradiol and Raloxifene treatment had no statistically significant effect on SOD activity.

Effects of insulin and sulphonylureas on insulin-like growth factor-I levels in streptozotocin-induced diabetic rats.

OBJECTIVE: Diabetes Mellitus is associated with decreased insulin-like growth factor-I (IGF-I) levels and also, poor growth in diabetes is related with low circulating levels of IGF-I. Insulin acts via an increase of IGF-I synthesis on growth. We studied the effects of insulin and sulphonylureas on serum IGF-I levels and aimed to evaluate the restoration of IGF-I in different therapeutic strategies. DESIGN AND SETTING: Thirty male rats were used in the study and diabetes was induced by a single intraperitoneal injection of streptozotocin (35 mg/kg body weight). After confirmation of hyperglycemia, rats were divided into three groups. The first group was treated with insulin, and second group with glimepiride, third group was not treated (control group). IGF-I levels were measured at basal, after streptozotocin and at the end of the treatment period. RESULTS: Serum IGF-I levels were found to decrease from 577.2 ng/ml to 253.0 ng/ml after streptozotocin (p<0.005). After 1 month, IGF-1 levels were found 524.0 ng/ml in insulin group, 449.3 ng/ml in sulphonylurea group, and 313.1 ng/ml in control group. The increase in IGF-I was statistically significant in insulin group (p<0.005), and in sulphonylurea group (p<0.05), but it was not significant in control group (p>0.05). CONCLUSIONS: Serum IGF-I levels decrease in diabetes and insulin treatment restores IGF-I depletion significantly. And although less effective, treatment with glimepiride restores IGF-I levels significantly.