Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human cytomegalovirus (HCMV) was recently demonstrated in the pancreas of about half the patients with type 2 diabetes mellitus in the absence of mumps, rubella or Coxsackie B virus. The present study addresses the question as to whether type 2 diabetes with an HCMV-positive pancreas differs from those with HCMV-negative pancreases with respect to age, sex, treatment, duration of disease, volume densities of B-cells and D-cells, mRNA levels of insulin and somatostatin, islet amyloid peptide deposits and major histocompatibility complex (MHC) class I and class II gene transcription, and protein expression. HCMV-positive type 2 diabetic patients showed a tendency towards a shorter duration of disease and significantly increased levels of MHC class II on RNA. In addition, expression of MHC class II product (HLA-DR) was identified in duct epithelial cells and/or islet cells in 9 diabetic pancreases and in 2 non-diabetic glands. No MHC class I expression could be detected. No other clinical differences between HCMV-positive and HCMV-negative glands were found. All 10 HCMV-positive diabetics showed a strong expression of MHC class II mRNA in the pancreas. By immunocytochemistry, 4 of 10 demonstrated expression on the islets; three of ten also expressed MHC DR beta on ductal cells. This finding might be related to the viral infection, as only 2 of the 9 HCMV-negative patients were HLA-DR beta positive and none of the non-diabetic controls showed increased levels of MHC class II mRNA. These data suggest that HCMV infection in the pancreas is associated with type 2 diabetes. However, no conclusions as to a role of this virus in the aetiopathology of type 2 diabetes can be drawn at present.
 ...
PMID:Human cytomegalovirus in the pancreas of patients with type 2 diabetes: is there a relation to clinical features, mRNA and protein expression of insulin, somatostatin, and MHC class II? 136 Jul 19

After the death of a 12-year old girl with newly discovered insulin-dependent diabetes mellitus, we used monoclonal antibodies in an effort to identify the cells invading the pancreas. The majority of infiltrating lymphocytes were of the T cytotoxic/suppressor phenotype, but other T-cell subpopulations were present. Some of the T cells were "activated" (positive for HLA-DR antigen, and the interleukin-2 receptor). Immunocytes bearing IgG were scattered in the gland, and complement-fixing IgG antibodies were deposited in some islets. Increased expression of Class I (HLA-A, B, and C) molecules was observed in the affected islet cells, and in damaged islets showing scant lymphocytic infiltration, some beta cells (still producing insulin), but not glucagon or somatostatin cells, were HLA-DR positive. The capillary endothelium was markedly dilated and strongly HLA-DR positive. These findings may contribute to an understanding of the sequence of events leading to the destruction of beta cells in classic Type I diabetes mellitus.
 ...
PMID:In situ characterization of autoimmune phenomena and expression of HLA molecules in the pancreas in diabetic insulitis. 315 65

We report the case of a 62-year-old woman who was admitted to our hospital with diabetic ketoacidosis. Her urinary C-peptide was 3.5 micrograms/day, HLA typing was DR9, and serum was positive for islet cell antibodies. There was no significant increase in the major viral titer. Pancreatic head tumor was suspected, and pancreaticoduodenectomy was performed. The pathology of this tumor was polycystic adenoma. We examined the surgical specimen from around the tumor histologically. The pancreatic islets had decreased in number. The immunohistochemical staining of islets for insulin, glucagon and somatostatin showed that the number of B cells had decreased remarkably, while A and D cells were preserved. Marked lymphocytic infiltration was observed in the islets. The majority of lymphocytes were helper/inducer and suppressor/cytotoxic T cells, which did not express HLA-DR antigen or interleukin-2 receptor. No NK cells were present in the islets. The present case, which was examined histologically in detail, is consistent with the previously proposed hypothesis that autoimmunity might play an important role in the pathogenesis of insulin-dependent diabetes mellitus.
 ...
PMID:Type 1 (insulin-dependent) diabetic patient with remarkable infiltration of lymphocytes to the islets. 795 31

The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on purified peripheral blood human monocytes. Somatostatin, at concentrations thought to be physiologic (10(-10)-10(-7) M), regulated monocyte/macrophage responses to (LPS) stimulation, as reflected by interleukin production. In particular, somatostatin had direct inhibitory effects on TNF-alpha, IL-1 beta, and IL-6 secretion by LPS-activated monocytes, while the decrease on IL-8 synthesis was modulated mainly by the action of somatostatin on TNF-alpha and IL-1 beta. In fact, the addition of these two inflammatory cytokines to the monocyte culture medium was able to induce IL-8 expression, as demonstrated by mRNA analysis, also in presence of the neuropeptide. Although somatostatin affected IL-8 production in an indirect way, it suppressed directly the chemotactic response of neutrophils to IL-8. Finally, somatostatin downregulation of monocyte activation was confirmed by the decrease of HLA-DR expression on cell plasma membranes (52% versus 33%). Our results confirm that somatostatin exerts preferential effects on the suppression of immunoreactions by modulating cytokine production and activity.
 ...
PMID:Modulation of cytokine production in activated human monocytes by somatostatin. 892 6

This study presents an immunohistochemical characterization of somatostatin-positive dendritic cells in psoriatic lesions. Somatostatin is a neuropeptide with inhibitory action on several neuropeptides and hormones, but also with immunomodulating properties, and has been used in several studies as treatment for psoriasis. The number of somatostatin-positive dendritic cells was found to be larger in psoriatic lesions than in normal skin of psoriasis patients and healthy controls. Colocalization of somatostatin and HLA-DR immunoreactivity was demonstrated in a subgroup of dendritic cells of psoriatic skin, whereas double-labelled cells were not found in uninvolved skin. The somatostatin-positive cells in the epidermis and dermis did not co-express CD1a, CD35, CD45RB, CD45RO, CD68, factor XIIIa or S-100. On the basis of these findings, the somatostatin-positive cells seem to represent a specific population of dermal dendritic cells, distinct from Langerhans' cells and factor XIIIa-positive cells, which are found in elevated amounts in chronic plaque psoriasis.
 ...
PMID:Colocalization of somatostatin- and HLA-DR-like immunoreactivity in dendritic cells of psoriatic skin. 960 36

The thymus provides an optimal humoral microenvironment for the development of immunocompetent T cells. Although yolk sac derived pre-T, committed hematopoietic stem cells enter the thymus using a homing receptor, the immigration process also requires secretion of a peptide called thymotaxin by the cells of the reticulo-epithelial (RE) network of the thymic cellular microenvironment. The majority of RE cells have a round or irregular pale nucleus, which contains few, scattered, chromatin granules with a defined, spherical nucleolus, rich in basic histones. Their cytoplasm occasionally displays RNP granules, and is rich in non-histone proteins, fine phospholipid, lipid or cholesterin granules, and vacuoles filled with secreted substances. The cells of the subcapsular, endocrine RE cell layer (giant or nurse cells), characterized by PAS positive granules, express A2B5/TE4 cell surface antigens and MHC Class I (HLA A, B, C) molecules. In contrast to medullar RE cells, these subcapsular nurse cells also produce thymosins beta 3 beta 4. Thymic nurse cells (TNCs) display a neuroendocrine cell specific immunophenotype (IP): Thy-1+, A2B5+, TT+, TE4+, UJ13/A+, UJ127.11+, UJ167.11+, UJ181.4+, and presence of common leukocyte antigen (CLA+). Medullar RE cells display MHC Class II (HLA-DP, HLA-DQ, HLA-DR) molecule restriction. These cells also contain transforming growth factor-beta (TGF-beta) type II receptors and participate in the positive selection of T cells. Transmission electron-microscopic (TEM) observations have defined four functional subtypes of medullar RE cells: undifferentiated, squamous, villous, and cystic. All subtypes are connected by desmosomes. Immunocytochemical observations have shown that the secreted thymic hormones, thymosin alpha 1 and thymopoietin (and its short form, thymopentin or TP5), are produced by the same RE cells. Thymic RE cells also produce numerous cytokines including IL1, IL6, G-CSF, M-CSF, and GM-CSF that likely are important in various stages of thymocyte activation and differentiation. The co-existence of pituitary hormone and neuropeptide secretion, such as growth hormone, prolactin, adrenocorticotropic hormone, thyroid stimulating hormone, triiodothyronine, somatostatin, oxytocin, follicle stimulating hormone, luteinizing hormone, arginine vasopressin, growth hormone releasing hormone, corticotropin releasing hormone, nerve growth factor, vasoactive intestinal peptide, (pro) enkephalin, and beta-endorphin, production of a number of interleukins and growth factors, as well as the expression of receptors for all, by the same RE cell is an unique molecular biological phenomenon. These data illustrate the immensely important and diverse immuno-neuroendocrine functions of the thymic RE cellular network. Based on our systematic observations of the thymus in humans and other mammalian species, we suggest that the thymic RE cell network represents an extremely important cellular and humoral microenvironment in homeopathic regulatory mechanisms of the multicellular organism. Intrathymic T lymphocyte selection is a complex, multistep process, influenced by several functionally specialized RE cell subtypes and under constant immuno-neuroendocrine regulation, reflecting the dynamic changes of the organism.
 ...
PMID:Molecular biological ontogenesis of the thymic reticulo-epithelial cell network during the organization of the cellular microenvironment. 1045 6