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I mRNA (i + mrna)

Distribution by Scientific Domains

Medical Sciences	71%

Selected Abstracts

Expression of CRABP I mRNA in fastigial cells of the developing cerebellum

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002
Rosalba Parenti
Abstract The expression of the cellular retinoic acid binding protein type I (CRABP I) was examined in the early phase of cerebellar development in the mouse. The CRABP I was expressed from embryonic day (E) 10.5 to E15.5 in the cerebellar plate. The expression was diffused at E10.5,E11.5 and thereafter localized in a small rostrodorsal area of the cerebellar territory of both sides. By using in situ hybridization and both immunohistochemistry and carbocyanine tracing procedures, we identified the fastigial cells as the population that expresses CRABP I in the cerebellum. The results suggest that these cells play a critical role in the early development of the cerebellum. [source]

Transcription of major histocompatibility complex class I (Kb) and transporter associated with antigen processing 1 and 2 genes is up-regulated with age

IMMUNOLOGY, Issue 3 2004
Alain G. Assounga
Summary The transporter associated with antigen processing 1 and 2 (TAP1 and TAP2) genes belong to the ATP-binding cassette family of transporter genes. They provide peptides necessary for the assembly of major histocompatibility complex (MHC) class I molecules by transporting these peptides into the endoplasmic reticulum. As MHC class I protein expression increases with age, we have explored the effect of age on the transcription of MHC class I genes (Kb) and TAP1 and TAP2 genes in C57BL/6 mice. Blood and spleen lymphocytes were isolated from mice aged from 3 months to over 24 months. RNA was extracted and mRNA for Kb, TAP1, TAP2 was quantified using slot-blot hybridization followed by densitometry. There was a parallel age-related increase (1·5-fold) in blood lymphocyte mRNA of these genes from 3 months to 21 months. In mice over 24 months old there was a decrease in Kb and TAP1 mRNA, but an increase in TAP2 mRNA. In spleen lymphocytes an age-related increase in all three mRNA species occurred throughout life. While MHC class I and Tap genes underwent very similar age-related changes, MHC class I mRNA was about 50 times more abundant than either TAP1 or TAP2 mRNA. [source]

Effects of vegetable feed ingredients on bone health in Atlantic salmon

JOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010
P. G. Fjelldal
Summary The aim of the present study was to examine if dietary inclusion of vegetable lipids (VL) and proteins (VP) influenced markers of bone health in Atlantic salmon. Triplicate groups were fed one of four different diets; 100% fish protein (FP) and fish lipids (FL) (FPFL), 80% VP and 35% VL (80VP35VL), 40% VP and 70% VL (40VP70VL), or 80% VP and 70% VL (80VP70VL) for 12 months on-growth in sea water. Fish were analyzed for vertebral bone mineralization (mineral content, as % of bone dry weight), vertebral deformities (radiology), vertebral bone mRNA expression of factors involved in mineralization (bone gla protein, bgp) and growth regulation (igf-I and growth hormone receptor), as well as plasma vitamin D metabolites. The fish grew from 0.35 to 4 kg during the experimental period. At the end of the experiment, significantly lower prevalence of fish with one or more deformed vertebrae was observed in the 80VP70VL group (11%) compared to the other groups (33,43%). There was a significant higher relative expression of igf -I mRNA in vertebral bone of fish fed the 80VP70VL diet compared to control fish (FPFL), while the other genes studied were unaffected. Elevated plasma 25-hydroxyvitamin D3 recorded in the marine feed group is discussed as a predictor for later development of bone deformities. In conclusion, the present study shows that high inclusion levels of vegetable lipids and proteins may have a positive effect on bone health in Atlantic salmon postsmolts. [source]

Growth Hormone-Releasing Peptide-6 Increases Insulin-Like Growth Factor-I mRNA Levels and Activates Akt in RCA-6 Cells as a Model of Neuropeptide Y Neurones

JOURNAL OF NEUROENDOCRINOLOGY, Issue 11 2005
L. M. Frago
Abstract Chronic systemic administration of growth hormone (GH)-releasing peptide-6 (GHRP-6), an agonist for the ghrelin receptor, to normal adult rats increases insulin-like growth factor (IGF)-I mRNA and phosphorylated Akt (pAkt) levels in various brain regions, including the hypothalamus. Because neuropeptide Y (NPY) neurones of the arcuate nucleus express receptors for ghrelin, we investigated whether these neurones increase their IGF-I and p-Akt levels in response to this agonist. In control rats, immunoreactive pAkt was practically undetectable; however, GHRP-6 increased p-Akt immunoreactivity in the arcuate nucleus, with a subset of neurones also being immunoreactive for NPY. Immunoreactivity for IGF-I was detected in NPY neurones in both experimental groups. To determine if activation of this intracellular pathway is involved in modulation of NPY synthesis RCA-6 cells, an embryonic rat hypothalamic neuronal cell line that expresses NPY was used. We found that GHRP-6 stimulates NPY and IGF-I mRNA synthesis and activates Akt in this cell line. Furthermore, inhibition of Akt activation by LY294002 treatment did not inhibit GHRP-6 induction of NPY or IGF-I synthesis. These results suggest that some of the effects of GHRP-6 may involve stimulation of local IGF-I production and Akt activation in NPY neurones in the arcuate nucleus. However, GHRP-6 stimulation of NPY production does not involve this second messenger pathway. [source]

Procollagen type I gene expression and cell proliferation are increased in lipodermatosclerosis

BRITISH JOURNAL OF DERMATOLOGY, Issue 2 2005
A.M. DeGiorgio-Miller
Summary Background, Lipodermatosclerosis (LDS) is characterized by a hardening and hyperpigmentation of lower leg skin as a consequence of chronic venous insufficiency. The degree of skin hardening or fibrosis associated with LDS is proposed to relate directly to skin breakdown and venous ulcer formation as well as to a subsequent delay in ulcer healing. Objectives, To determine whether elevated procollagen type I gene expression and increased cell proliferation are responsible for the fibrotic changes associated with LDS. Methods, Skin biopsies were obtained from the legs of patients with varying degrees of chronic venous disease and were assessed for procollagen gene expression by in-situ hybridization and for cell proliferation by immunolocalization of proliferating cell nuclear antigen. Results, The number of cells expressing procollagen type I mRNA (COL1A1) was significantly higher in the dermis of LDS-affected skin compared with samples from the other patient groups. In addition, there was a significant increase in the number of dermal fibroblasts undergoing proliferation in both LDS samples and skin samples prior to LDS changes compared with control samples. However, there was no significant difference in level of inflammation in biopsy samples between patient classes. Conclusions, These results suggest that enhanced cell proliferation and procollagen gene expression are both involved in LDS development. Furthermore, fibrotic changes may occur in the absence of, or subsequent to, any significant inflammatory response, indicating that additional profibrotic factors produced in the skin as a consequence of chronic venous insufficiency may play a role in LDS formation. [source]

Inhibition of calcium-calmodulin kinase restores nitric oxide production and signaling in submandibular glands of a mouse model of salivary dysfunction

BRITISH JOURNAL OF PHARMACOLOGY, Issue 8 2004
Florencia Rosignoli
Nitric oxide is an intracellular and diffusible messenger of neurotransmitters involved in salivary secretion, as well as an inflammatory mediator in salivary gland diseases. It is synthesized by three different isoforms of nitric oxide synthase (NOS), each subject to a fine transcriptional, post-transcriptional and/or post-translational regulation. Our purpose was to study the possible mechanisms leading to NOS downregulation in submandibular glands of normal mice and in the nonobese diabetic (NOD) mouse model of salivary dysfunction with lower NOS activity. NOS activity and cGMP accumulation were determined by radioassays in submandibular glands of both mice in the presence of the protein kinase inhibitors KN-93 and bisindolylmaleimide. NOS I mRNA and protein expression and localization were assessed by RT,PCR, Western blot and immunohistochemistry. A downregulatory effect of calcium,calmodulin kinase II (CaMK II) on NOS activity in submandibular glands of both NOD and BALB/c mice was observed. Our results are consistent with a physiological regulation of NOS activity by this kinase but not by PKC in normal BALB/c mice. They are also supportive of a role for CaMK II in the lack of detectable NOS activity in submandibular glands of NOD mice. KN-93 also restored cGMP accumulation in NOD submandibular glands. The downregulation of NOS in NOD mice seems to be mainly mediated by this kinase rather than the result of a lower expression or different cellular localization of the enzyme. It was not related to different substrate or cofactors availability either. British Journal of Pharmacology (2004) 143, 1058,1065. doi:10.1038/sj.bjp.0705952 [source]

CPT-11 May Provide Therapeutic Efficacy for Esophageal Squamous Cell Cancer and the Effects Correlate with the Level of DNA Topoisomerase I Protein

CANCER SCIENCE, Issue 12 2001
Yasuaki Nakajima
CPT-11 is a potent anti-cancer drug and a specific inhibitor of DNA topoisomerase I (Topo I). In this study, we aim to evaluate the effects of CPT-11 on esophageal squamous cell cancers (ESCC) and to determine the correlation between the effects and the levels of Topo I expression. We examined the growth-inhibitory effect caused by SN-38, an active metabolite of CPT-11, in 14 human ESCC cell lines established from 10 primary and 4 metastatic lesions. CPT-11 was considered effective against 5 cell lines from primary lesions and one from metastatic lesions, and thus may show therapeutic efficacy against both primary and metastatic ESCC tumors. Although Topo I mRNA levels in these 14 ESCC cell lines, as quantitated by northern blot analysis, showed no correlation with the IC50 values, Topo I protein levels, as quantitated by western blot analysis, showed an inverse correlation with the IC50 values. Topo I protein levels could be an indicator of sensitivity to CPT-11. We also determined Topo I protein levels in 40 ESCC tumors and matched normal mucosae. Thirty-four tumors showed 1.2-22.3-fold increases in Topo I levels. Two patients receiving pre-operative chemotherapy and one receiving radiotherapy exhibited increased Topo I protein levels in their tumor lesions. It appeared that CPT-11 could provide selective therapeutic efficacy against ESCC tumors. CPT-11 may be effective for the treatment of metastatic ESCC tumors and as a second-line anti-cancer drug for ESCC. [source]