OBJECTIVE The aim of this study was to examine the effects of ovariectomy and ovariectomy followed by estradiol benzoate administration on the ultrastructure of pinealocytes in female rat. DESIGN For this purpose 15 female Wistar rats were used. Animals were divided into three groups. Group I and II were designated as sham-ovariectomized (control) and ovariectomized, respectively. Group III w...

The leptin hormone is important to satiety and an important link between the nutritional status and reproductive processes. Owing to the contradictory effects of leptin on the ovary and the failure to clarify the precise mechanism by which leptin affects the ovary, our aim was to contribute to evaluation if leptin can directly regulate the gene expression of leptin itself and its receptors, and...

Circulating concentrations of leptin and IGF-I, leptin gene expression, and serum binding of [126I]ovine leptin in cattle during pubertal development, as well as leptin gene expression and circulating concentrations of leptin during the estrous cycle and different calendar seasons, were investigated. Multivariate regression analysis was utilized to evaluate temporal changes in BW, leptin mRNA, ...

OBJECTIVE Adverse metabolic changes associated with loss of ovarian function increase the risk of developing metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) in postmenopausal women. Naringenin improves metabolic disturbances in vitro and in vivo. In the present study, we tested the effects of naringenin on metabolic disturbances resulting from estrogen deficiency in ovariectomi...

Leptin is an adipocyte-derived cytokine coded by the obese gene, not only regulates metabolism, but also participates in hematopoiesis. Aberrant leptin levels in patients with hematologic malignancies were observed and associates with clinical characters, such as body mass index (BMI), gender, blast cell percentage. Leptin concentrations alter while diseases progress or remission. Leptin recept...

Leptin inhibits feeding and decreases body weight. It may act partly by inhibiting hypothalamic neurons that express neuropeptide Y, a powerful inducer of feeding and obesity. These neuropeptide Y neurons express the Ob-Rb leptin receptor and are overactive in the fatty (fa/fa) Zucker rat. The fa mutation affects the extracellular domain of the leptin receptor, but its impact on leptin action a...

The obesity gene (ob) in mice encodes a protein produced by adipose tissue, leptin, which regulates body weight (3). Under experimental conditions, leptin affects the central nervous system and tends to reduce appetite and increase energy expenditure. Numerous studies have shown an increased expression of the ob gene (mRNA-leptin) in adipocytes or a marked increase in serum leptin concentration...

Leptin regulates energy homoeostasis through central and peripheral mechanisms. Initial steps in leptin action include signalling through a cytokine-like receptor which activates the JAK/STAT pathway. We investigated whether the metabolic effects of leptin in muscle could be mediated by the AMP-activated protein kinase (AMP kinase). Through studies involving leptin injection intrahypothalamical...

T he Lepr/Lepr mouse is an autosomal recessive model of extreme obesity that phenotypically appears very similar to the Lepr/Lepr mouse, in which the leptin protein is absent (1). However, in the Lepr/Lepr mouse, the leptin protein is structurally normal (1). Leptin is ineffectual when injected into Lepr/Lepr mice, indicating that they are resistant to the action of this hormone (1). Recently, ...