T-cell subpopulations express a different pattern of dopaminergic markers in intra- and extra-thymic compartments.

An involvement of dopamine in regulation of the immune function has been assessed and dopaminergic system has been found widely represented in thymus. Nevertheless detail on the characterization of dopaminergic system in assisting thymocytes development and lymphocytes mature physiology are still lacking. The present study was designed to characterize dopamine plasma membrane transporter (DAT), vesicular dopamine transporters (VMAT)-1 and -2, and dopamine D1-like and D2-like receptors in rat thymocytes, splenocytes and peripheral blood mononuclear cells. Western blot and RT-PCR analyses, performed on these cells, showed an expression of dopamine transporters and receptors during thymocyte development (when of CD4 and CD8 markers are differently expressed). Furthermore FACS analysis, indicates that DAT and dopamine D1-like receptors are expressed at high levels in thymocytes, splenocytes, and peripheral lymphocytes. The percentage of CD4+ CD8+ (double-positive) thymocytes expressing dopaminergic markers was significantly higher compared to the percentage of double-negative ones. The percentage of CD8+ single positive cells expressing dopaminergic markers was significantly higher than that of CD4+ cells. The results suggest that the dopaminergic system plays a role in the thymus microenvironment during T-cell development. The more pronounced expression of dopaminergic markers in CD8+ subsets suggests that dopamine plays a role in development of cytotoxic T-cells. Our findings indicate dopaminergic system to have a role during the maturation and selection of lymphocytes, and support its involvement in the active phases of immune response.

Single dose bioavailability and pharmacokinetic study of a innovative formulation of α-lipoic acid (ALA600) in healthy volunteers.

AIM: α-Lipoic acid is an important micronutrient with several pharmacological as well as antioxidant properties. The present study was aimed to examine the human bioavailability, pharmacokinetics (PK) and tolerability of an innovative oral formulation (ALA600) containing racemic α-lipoic acid 600 mg. METHODS: After a single 600-mg oral administration in healthy volunteers, blood samples were collected up to 8 hours post dosing, and plasma α-lipoic acid concentrations were determined by Liquid Chromatography-Mass Spectrometry (LC-MS) detection. RESULTS: The PK data revealed a short time to reach plasma peak oncentrations (50.8± 4.2 min) with a C(max) of 6.86±1.29 µg/mL. The C(max) implying that the new pharmaceutical form positively influences absorption and absorption time. The AUC value of 5.65±0.79 µg/mL*h is the more reliable measure of new formulation bioavailability. The half-life and MRT values further show that new formulation is absorbed consistently and rapidly and is eliminated efficiently. These PK data appear to promote further refinement of present formulation. Should the authors compare the obtained data with the recent published data, the new formulation of α-lipoic acid tends to show an improvement of C(max) value (2.5-5.4 times) and AUC (1.8 times). CONCLUSION: ALA600 formulation is characterized by rapid absorption, high bioavailability, brief half-life and low toxicity. These PK parameters could significantly increase clinical use of lipoic acid with improvement of the therapeutic effects at the cellular level and might also prove to be the most suitable formulation for chronic administration such as peripheral neuropathies.

Ultrastructure and lectin cytochemistry of secretory cells in lingual glands of the Japanese quail (Coturnix coturnix japonica).

In the present study, as continuation of our previous research, Japanese quail (Coturnix coturnix japonica) lingual glands were investigated by means of transmission electron microscopy (TEM) to understand the cytoarchitecture and the subcellular sugar distribution within the different secretory structures. Indeed, glycosidic residues were visualized by applying an indirect technique of binding and the terminal sialoglycoconjugate sequences were characterized by employing sialidase digestion combined with lectin affinity. The ultrastructural analysis revealed an unusual cytoarchitecture of the caudal portion of anterior lingual gland that was composed of both secretory cells, filled with granules, and non-secretory cells, filled with mitochondria. Conversely, the posterior lingual gland was composed of secretory units of lingual glands only containing mucous cells filled with secretory granules with a variable morphology, including bipartite features characterized by an electron-lucent matrix and one or more electron-dense areas. Actual findings further supported that the quail lingual glands produce sialoglycoconjugates characterized by a heterogeneous composition. In conclusion, the cytological characteristics and the carbohydrate composition of quail lingual glands suggest that, analogously to mammal salivary glands, avian lingual glands could also be involved in several functions that can be correlated with the occurrence of sialic acids.

Phthalate esters immunolocalized in the gastrointestinal tract of shi drum Umbrina cirrosa (L.) and rainbow trout, Oncorhynchus mykiss (W.).

The occurrence of phthalate esters in freshwater and marine aquacultural species like rainbow trout Oncorhynchus mykiss and shi drum Umbrina cirrosa, respectively, were determined by immunohistochemical approach. The results showed a similar distribution in the gastrointestinal tract of both species. In particular, intense immunoreactivity was found at gastric gland level. In the intestinal tract, goblet cells failed to stain, whereas enterocytes showed the highest binding of phthalates restricted to the apical cytoplasm. This distribution of phthalate esters at gastric gland and enterocyte level may have implications for the physiology of the digestive process and intestinal biotransformation. Phthalates are confirmed to be widely diffused contaminants, absorbed via the alimentary canal; thus a multidisciplinary approach could be useful to examine sea and freshwater environments.