Dietary Copper Affects Azoxymethane-Induced Intestinal Tumor Formation and Protein Kinase C Isozyme Protein and mRNA Expression in Colon of Rats

Abstract Background Several lines of evidence suggest the abnormalities of protein kinase C (PKC) signaling system in mood disorders and suicide based primarily on the studies of PKC and its isozymes in the platelets and postmortem brain of depressed and suicidal subjects. In this study we examined the role of PKC isozymes in depression and suicide. Methods We determined the protein and mRNA expression of various PKC isozymes in the prefrontal cortical region [Brodmann area 9 (BA9)] in 24 normal control (NC) subjects, 24 depressed suicide (DS) subjects and 12 depressed non-suicide (DNS) subjects. The levels of mRNA in the prefrontal cortex (PFC) were determined by qRT-PCR and the protein expression was determined by Western blotting. Results We observed a significant decrease in mRNA expression of PKCα, PKCβI, PKCδ and PKCε and decreased protein expression either in the membrane or the cytosol fraction of PKC isozymes - PKCα, PKCβI, PKCβII and PKCδ in DS and DNS subjects compared with NC subjects. Conclusions The current study provides detailed evidence of specific dysregulation of certain PKC isozymes in the postmortem brain of DS and DNS subjects and further supports earlier evidence for the role of PKC in the platelets and brain of adult and teenage depressed and suicidal population. This comprehensive study may lead to further knowledge of the involvement of PKC in the pathophysiology of depression and suicide.

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Regulation of arginine vasopressin mRNA in rat fetal hypothalamic cell culture. Role of protein kinases and glucocorticoids

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0100051 ◽

1993 ◽

Vol 10 (1) ◽

pp. 51-57 ◽

Cited By ~ 8

Author(s):

S-B Hu ◽

L A Tannahill ◽

S L Lightman

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Mrna Expression ◽

Protein Kinase A ◽

Arginine Vasopressin ◽

In Situ Hybridization Histochemistry ◽

Kinase C ◽

Kinase A

ABSTRACT Studies have been performed to investigate the regulation of arginine vasopressin (AVP) mRNA expression in fetal hypothalamic cultures. AVP mRNA-positive neurones were identified by in-situ hybridization histochemistry, and changes in mRNA expression were quantitated by nuclease protection assay. Both protein kinase C and protein kinase A activators increased the expression of AVP mRNA, in contrast to dexamethasone, which inhibited the responses to both protein kinase C and protein kinase A activation.

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A possible role for protein kinase C in CO2/H+-induced c-fos mRNA expression in PC12 cells

Respiration Physiology ◽

10.1016/s0034-5687(97)00115-1 ◽

1998 ◽

Vol 111 (2) ◽

pp. 127-135 ◽

Cited By ~ 13

Author(s):

N.T Kuo ◽

F.H Agani ◽

M.A Haxhiu ◽

C.H Chang

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Mrna Expression ◽

Pc12 Cells ◽

Kinase C

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Coordinate changes in gene expression which mark the spinous to granular cell transition in epidermis are regulated by protein kinase C.

The Journal of Cell Biology ◽

10.1083/jcb.120.1.217 ◽

1993 ◽

Vol 120 (1) ◽

pp. 217-225 ◽

Cited By ~ 180

Author(s):

A A Dlugosz ◽

S H Yuspa

Keyword(s):

Gene Expression ◽

Protein Kinase C ◽

Protein Kinase ◽

Mrna Expression ◽

Granular Cell ◽

Cell Markers ◽

Kinase C ◽

Coordinate Changes ◽

Cell Transition ◽

In Cells

The protective function of skin depends on successful completion of a tightly regulated multi-step differentiation program, during which the induction of markers for a specific stage in epidermal differentiation is coupled to repression of markers expressed at the preceding stage. We have explored the role of protein kinase C (PKC) in this process using an in vitro model system, in which cultures of primary mouse epidermal keratinocytes are induced to terminally differentiate by raising the Ca2+ concentration in the medium from 0.05 to 0.12 mM. At doses which activate PKC, 12-O-tetradecanoylphorbol-13-acetate (TPA) and 1-oleoyl-2-acetylglycerol block Ca(2+)-mediated induction of the spinous cell markers keratins K1 and K10 at both the protein and mRNA level. TPA and 1-oleoyl-2-acetylglycerol also rapidly repress K1 and K10 mRNA expression when added to differentiating keratinocyte cultures already expressing these markers. The inhibition of K1 mRNA expression by TPA is blocked in cells where PKC has been inactivated with bryostatin. TPA-mediated loss of K1 mRNA is also blocked in cells exposed to cycloheximide or actinomycin D implicating a PKC-induced protein factor in this process. The loss of K1 mRNA in TPA-treated cultures is the result of both a selective destabilization of K1 transcripts and a rapid inhibition of K1 gene transcription. In contrast to the dramatic repression of mRNAs typical for spinous cell differentiation, activation of PKC concurrently enhances expression of mRNAs and proteins for the granular cell markers loricrin and filaggrin. This response does not occur in cells pre-treated with bryostatin to inactivate PKC. Our results suggest that PKC is a fundamental regulator of the coordinate changes in keratinocyte gene expression that occur during the spinous to granular cell transition in epidermis.

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Calcitonin Induces 25-Hydroxyvitamin D31α-Hydroxylase mRNA Expression via Protein Kinase C Pathway in LLC-PK1Cells

Journal of the American Society of Nephrology ◽

10.1681/asn.v10122474 ◽

1999 ◽

Vol 10 (12) ◽

pp. 2474-2479

Author(s):

NORIKO YOSHIDA ◽

TADASHI YOSHIDA ◽

AKIRA NAKAMURA ◽

TOSHIAKI MONKAWA ◽

MATSUHIKO HAYASHI ◽

...

Keyword(s):

Vitamin D ◽

Protein Kinase C ◽

Protein Kinase ◽

Mrna Expression ◽

Protein Kinase A ◽

Mrna Levels ◽

Hydroxyvitamin D ◽

Kinase C ◽

25 Hydroxyvitamin D ◽

Kinase A

Abstract. The biosynthesis of 1α, 25-dihydroxyvitamin D3from 25-hydroxyvitamin D3is catalyzed by 25-hydroxyvitamin D31α-hydroxylase (CYP27B1) in renal proximal tubules. It was recently demonstrated that LLC-PK1cells express CYP27B1 mRNA, which is regulated by intracellular cAMP but not vitamin D3. To clarify the effect of calcitonin on vitamin D3metabolismin vitro, LLC-PK1cells were incubated with hormonal factors, and expression of CYP27B1 mRNA was measured by quantitative reverse transcription-PCR. Calcitonin at 100 nmol/L significantly increased CYP27B1 mRNA expression by 24 h (271 ± 21% of control). Incubation with calcitonin over a range of 1 μmol/L to 1 pmol/L resulted in a concentration-dependent increase in CYP27B1 mRNA levels. It is known that the calcitonin receptor has dual intracellular signaling pathways, via protein kinases A and C. Both 500 μmol/L 8-bromo-cAMP, a protein kinase A activator, and 100 nmol/L phorbol 12-myristate 13-acetate, a protein kinase C activator, increased CYP27B1 mRNA levels at 24 h (207 ± 54 and 246 ± 58% of control, respectively). However, calcitonin-induced CYP27B1 mRNA expression was only inhibited by the protein kinase C inhibitors staurosporine and calphostin C. The protein kinase A inhibitors Rp-cAMPS at 10 and 100 μmol/L and H-89 at 10 μmol/L had no effect on the action of calcitonin, in spite of cAMP-activation by calcitonin. The present data suggest that calcitonin upregulates CYP27B1 mRNA expression via the protein kinase C pathway in LLC-PK1cells.

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