Stabilization of ornithine decarboxylase and N1-spermidine acetyltransferase in rat liver by methylglyoxal bis(guanylhydrazone)

Karvonen, Eira; Pösö, Hannu

doi:10.1016/0167-4838(84)90014-1

Cited by 25 publications

(6 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fact that putrescine increases by a greater amount than spermidine and spermine decrease (Tables 1 and 3), leading to a net increase in total diamine plus polyamine content in the cell, shows that putrescine is much less effective in decreasing ODC activity than are the polyamines spermine and spermidine. These results are in agreement with early studies which showed that MGBG treatment led to an increase in ODC activity in rat liver [35][36][37], but in these experiments the direct effects of MGBG itself cannot be ruled out, since this compound is a polyamine analogue and has numerous other effects in addition to its inhibition of AdoMetDC [2,4,16]. It should be emphasized that, although putrescine does not appear to regulate ODC, it does play an important role in the control ofmammalian polyamine concentrations.…”

Section: Odc Activity (In 1 /Mand 4 /Tm-discussionsupporting

confidence: 93%

Effect of inhibitors of S-adenosylmethionine decarboxylase on the contents of ornithine decarboxylase and S-adenosylmethionine decarboxylase in L1210 cells

Madhubala

Secrist

Pegg

1988

Biochemical Journal

View full text Add to dashboard Cite

Treatment of L1210 cells with either of two inhibitors of S-adenosylmethionine decarboxylase (AdoMetDC), namely 5'-deoxy-5'-[N-methyl-N-[2-(amino-oxy)ethyl])aminoadenosine or 5'-deoxy-5'-[N-methyl-N-(3-hydrazinopropyl)]aminoadenosine, produced a large increase in the amount of ornithine decarboxylase (ODC) protein. The increased enzyme content was due to a decreased rate of degradation of the protein and to an increased rate of synthesis, but there was no change in its mRNA content. The inhibitors led to a substantial decline in the amounts of intracellular spermidine and spermine, but to a big increase in the amount of putrescine. These results indicate that the content of ODC is negatively regulated by spermidine and spermine at the levels of protein translation and turnover, but that putrescine is much less effective in bringing about this repression. Addition of either spermidine or spermine to the cells treated with the AdoMetDC inhibitors led to a decrease in ODC activity, indicating that either polyamine can bring about this effect, but spermidine produced effects at concentrations similar to those found in the control cells and appears to be the physiologically important regulator. The content of AdoMetDC protein (measured by radioimmunoassay) was also increased by these inhibitors, and a small increase in its mRNA content was observed, but this was insufficient to account for the increase in protein. A substantial stabilization of AdoMetDC occurred in these cells, contributing to the increased enzyme content, but an increase in the rate of translation cannot be ruled out.

show abstract

Section: Odc Activity (In 1 /Mand 4 /Tm-discussionsupporting

confidence: 93%

Effect of inhibitors of S-adenosylmethionine decarboxylase on the contents of ornithine decarboxylase and S-adenosylmethionine decarboxylase in L1210 cells

Madhubala

Secrist

Pegg

1988

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…These cells, which were isolated by McCann, Mamont and colleagues because of their resistance to ornithine decarboxylase inhibitors, have an elevated level of ODC due to a substantial increase in its half-life (Pritchard et al, 1982. A human cell line resistant to DFMO containing elevated levels of ODC with a greatly increased half-life has also been reported (Poso et al, 1984). Such cell variants provide a useful system in which the critical factors for the degradation of ODC may be studied.…”

Section: Inhibitors Of Ornithine Decarboxylasementioning

confidence: 99%

Recent advances in the biochemistry of polyamines in eukaryotes

Pegg¹

1986

Biochemical Journal

1,545

780

View full text Add to dashboard Cite

“…Stabilization of ODC is involved in various types of ODC induction, such as that in the kidney of androgen-treated female mice [37][38][39] and that in cells treated with amino acids such as asparagine or glutamine [40][41][42], hypotonic medium [41,[43][44][45], or inhibitors of polyamine synthesis [46][47][48][49][50]. Conversely, ODC is rapidly destabilized by removal of stabilizing amino acids [40], reversal to isotonicity [40,45], or addition of polyamines [51][52][53].…”

Section: Historical Background Rapid Turnover Of Odcmentioning

confidence: 99%