Acute and chronic effects of insulin, serum, phorbol ester and staurosporine on cell growth and myo-inositol transport in RPE. [Retinal pigment epithelial cells]

Conference · Mon Feb 26 04:00:00 EST 1990 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5610505

Khatami, M ^[1]

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1. Univ. of Philadelphia, PA (United States)

The presence of a Na{sup +}-dependent active process for myo-inositol (MI) uptake, sharing a common carrier system with glucose and sensitive to phlorizin has been established in cultures of retinal pigment epithelial (RPE) cells. Bovine RPE cells were grown in DMEM containing 10% of 20% fetal calf serum (FCS) or 20% newborn serum (NBS), and in the absence or presence of 0.13-130 mU/ml insulin, 0.1 to 10 {mu}M phorbol,12-myristate-13 acetate (PMA) or 0.2 to 100 {mu}M staurosporine. The rate of uptake was studied by incubating the cells in BSS with 10 {mu}M {sup 3}H-MI for 60 minutes. Cellular growth (DNA synthesis) was measured by {sup 3}H-thymidine incorporation into DNA. Cells were confluent by 8 to 10 days after seeding when media contained 10 or 20% fcs. Feeding with 20% NBS delayed confluency by 6 to 11 days. The rate of MI uptake into 15 days culture was 158{+-}14, 48{+-}7 or 37{+-}6 pmole/60 minutes multiwell plate, when cells were grown in 10% or 20% FCS, or 20% NBS, respectively. Insulin in growth media, in a dose dependent fashion, stimulated both DNA synthesis (particularly at the logarithmic phase of growth), as well as accumulation of MI, by up to 45 and 42% respectively,. Addition of PMA in growth media also increased DNA synthesis and MI uptake by up to 100 and 70%, respectively. Staurosporine (0.2 {mu}M), together with PMA, in growth media reversed phorbol-induced stimulation of DNA synthesis and MI uptake. Staurosporine alone, in growth media, reduced MI uptake by 23%. Incubating RPE cells in the presence of either insulin or PMA (acute effect) did not significantly change the rate of MI uptake. These studies indicated that in RPE cells, insulin and other growth factors present in the serum were required for cellular proliferation. Neither insulin nor protein kinase C were immediately involved in the uptake of MI in RPE cells.

• OSTI ID: 5610505
• Report Number(s): CONF-9004153--
• Conference Information: Journal Name: FASEB Journal (Federation of American Societies for Experimental Biology); (United States) Journal Volume: 4:3
• Country of Publication: United States
• Language: English

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59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL TISSUES
AZINES
BIOCHEMICAL REACTION KINETICS
BLOOD SERUM
BODY
BODY AREAS
CARBOHYDRATES
CARCINOGENS
CELL PROLIFERATION
EPITHELIUM
ESTERS
EYES
FACE
HEAD
HETEROCYCLIC COMPOUNDS
HORMONES
HYDROGEN COMPOUNDS
INOSITOL
INOSITOLS
INSULIN
ISOTOPE APPLICATIONS
KINETICS
MONOSACCHARIDES
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PEPTIDE HORMONES
PHORBOL ESTERS
PHYSIOLOGY
PROTEINS
PYRIMIDINES
REACTION KINETICS
RETINA
RIBOSIDES
SACCHARIDES
SENSE ORGANS
THYMIDINE
TISSUES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
UPTAKE