Serum levels of leptin and adiponectin in patients with autoimmune Hashimoto's thyroiditis.

INTRODUCTION: Adipose tissue is immunologically and hormonally active, and these effects are mediated largely by adipocytokines. Thyroid hormones regulate metabolism and organ function, and Hashimoto's thyroiditis (HT) is the most common autoimmune disease affecting thyroid function. AIM: To evaluate the levels of the adipocytokines leptin and adiponectin in patients with autoimmune HT, and to perform a comparative intragroup analysis in patients with different stages of gland functional activity, and in a control group. MATERIALS AND METHODS: Ninety-five patients with HT and 21 healthy controls were enrolled in the study. Venous blood was taken without anticoagulants after at least 12 hours of fasting, and serum samples were frozen at -70°C until analysis. Serum levels of leptin and adiponectin were determined by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Serum levels of leptin in HT patients were higher than those in the control group (4.5±5.2 ng/mL vs. 1.9±1.3 ng/mL). The hypothyroid patient's group showed significantly higher levels of leptin than those of the healthy controls (5.1±5.2 ng/mL vs. 1.9±1.3 ng/mL), (p=0.031). Leptin levels correlated positively with body mass index (r=0.533, p.

Formulation and performance evaluation of betahistine dihydrochloride microspheres as sustained release systems.

UNLABELLED: Betahistine dihydrochloride is a histamine-like drug widely used in relieving the symptoms associated with Ménière's syndrome. Pharmacokinetic studies of betahistine have demonstrated that it has a short plasma half-life of 3-4 hours. In such cases frequent administration of the drug is required in order to keep plasma concentration within the therapeutic range. However, this may lead to noncompliance and aggravate patients' comfort. An advanced approach for achieving sustained release of drugs is their incorporation in microparticulate carriers. AIM: To design a sustained release microsphere formulation of betahistine providing reduced dose frequency and lower risk of side effects occurrence. MATERIALS AND METHODS: Betahistine-loaded chitosan microspheres were obtained via W/O emulsion solvent evaporation technique and were characterized for particle size, drug loading and entrapment efficiency. Drug release into phosphate buffer saline pH 7.4 was performed and dissolution profiles of the formulations were obtained. To study the mechanism of drug release from the microspheres the dissolution data was fitted to various mathematic models. RESULTS: Betahistine-loaded microspheres were produced with a high drug loading and entrapment efficiency. The microcarriers were spherical in shape with mean particle size of 3.82 µm to 7.69 µm. Betahistine release studies from the microspheres showed similar and slightly increasing dissolution profiles. The drug release proceeded in a controlled manner following Fickian diffusion. CONCLUSION: The obtained results suggest that betahistine-loaded chitosan microspheres prepared by solvent evaporation method are capable of sustained release of drugs and therefore can be used as drug delivery systems in the treatment of Ménière's syndrome.