Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.11.13 (
protein kinase C
)
49,245
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Mast cells have been studied extensively for their involvement in allergic reactions, where they secrete numerous powerful mediators in response to immunoglobulin E and specific antigens. However, they are also triggered by neuropeptides, they have been found in close contact with neurons, and they are activated in diseases such as angioedema, interstitial cystitis and irritable
bowel disease
, the prevalence of which is much higher in women. When tested on purified rat peritoneal mast cells, 17 beta-estradiol augmented secretion of histamine and serotonin, starting at 1 microM and in a dose-dependent manner, whether stimulated by the mast cell secretagogue compound 48/80 or the neuropeptide substance P. However, 17 beta-estradiol did not augment mast cell secretion stimulated by immunoglobulin E and specific antiserum indicating that immunologic stimulation is under different regulation. Testosterone inhibited secretion induced by compound 48/80. Tamoxifen, an estrogen receptor antagonist used in the treatment of breast cancer, inhibited serotonin and histamine release from purified rat peritoneal mast cells triggered by compound 48/80 or substance P. Tamoxifen also inhibited the increase in intracellular free Ca2+ originating from an influx of extracellular Ca2+ in response to compound 48/80. Moreover, tamoxifen antagonized the synergistic effect of phorbol myristate and the cation ionophore A23187 on mast cell secretion, suggesting that tamoxifen's inhibition may be due to regulation of
protein kinase C
activity. Tamoxifen may, therefore, have a beneficial effect in other neuroimmunoendocrine disorders both through estrogen receptor blockade and inhibition of mast cell secretion.
...
PMID:Estradiol augments while tamoxifen inhibits rat mast cell secretion. 138 69
Celiac disease is an autoimmune
enteropathy
caused by a permanent intolerance to gliadins. In this study the effects of two gliadin-derived peptides (PA2, PQPQLPYPQPQLP and PA9, QLQPFPQPQLPY) on TNFalpha production by intestinal epithelial cells (Caco-2) and whether these effects were related to protein kinase A (PKA) and/or -C (
PKC
) activities have been evaluated. Caco-2 cell cultures were challenged with several sets of gliadin peptides solutions (0.25 mg/mL), with/without different activators of PKA or
PKC
, bradykinin (Brdkn) and pyrrolidine dithiocarbamate (PDTC). The gliadin-derived peptides assayed represent the two major immunodominant epitopes of the peptide 33-mer of alpha-gliadin (56-88) (LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF). Both peptides induced the TNFalpha production triggering the inflammatory cell responses, the PA2 being more effective. The addition of the peptides in the presence of dibutyril cyclic AMP (cAMP), Brdkn or PDTC, inhibited the TNFalpha production. The
PKC
-activator phorbol 12-myristate 13-diacetate additionally increased the PA2- and PA9-induced TNFalpha production. These results link the gliadin-derived peptides induced TNFalpha production through cAMP-dependent PKA activation, where ion channels controlling calcium influx into cells could play a protective role, and requires NF-kappaB activation.
...
PMID:Gliadins induce TNFalpha production through cAMP-dependent protein kinase A activation in intestinal cells (Caco-2). 2051 34
Radiation
enteropathy
is a common complication in cancer patients following radiation therapy. Thus, there is a need for agents that can protect the intestinal epithelium against radiation. 12-O-tetradecanoylphorbol-13-acetate (TPA) has been shown to induce differentiation and/or apoptosis in multiple cell lines and primary cells. In the current report, we studied the function of TPA in radiation induced
enteropathy
in cultured rat intestinal epithelial cell line IEC-6 after ionizing radiation (IR) and in mice after high dose total-body gamma-IR (TBI). In IEC-6 cells, there were reduced apoptosis and cell cycle arrest in TPA treated cells after IR. We detected a four-fold increase in crypt cell survival and a two-fold increase in animal survival post TBI in TPA treated mice. The beneficial effects of TPA were accompanied by upregulation of stem cells markers and higher level of proteins that are involved in
PKC
signaling pathway. In addition, TPA also decreased the TBI-augmented levels of the DNA damage indicators. The effects were only observed when TPA was given before irradiation. These results suggest that TPA has the ability to modulate intestinal crypt stem cells survival and this may represent a promising countermeasure against radiation induced
enteropathy
.
...
PMID:12-O-tetradecanoylphorbol-13-acetate (TPA) increases murine intestinal crypt stem cell survival following radiation injury. 2854 17