• Home
  • Search Results
  • Progesterone induces apoptosis of insulin-secreting cells: insights into the molecular mechanism.

Progesterone induces apoptosis of insulin-secreting cells: insights into the molecular mechanism.

The Journal of endocrinology (2014-03-07)
V A Nunes, E P Portioli-Sanches, M P Rosim, M S Araujo, P Praxedes-Garcia, M M R Valle, L P Roma, C Hahn, E Gurgul-Convey, S Lenzen, A K Azevedo-Martins
ABSTRACT

Progesterone has been associated with the development of gestational diabetes (GD) due to the enhancement of insulin resistance. As β-cell apoptosis participates in type 1 and type 2 diabetes pathophysiology, we proposed the hypothesis that progesterone might contribute to the development of GD through a mechanism that also involves β-cell death. To address this question, RINm5F insulin-producing cells were incubated with progesterone (25-100 μM), in the presence or absence of α-tocopherol (40 μM). After 24 or 48 h, membrane integrity and DNA fragmentation were analyzed by flow cytometry. Caspase activity was used to identify the mode of cell death. The involvement of endoplasmic reticulum stress in the action of progesterone was investigated by western blotting. Oxidative stress was measured by 2',7'-dichlorofluorescein diacetate (DCFDA) oxidation. Isolated rat islets were used in similar experiments in order to confirm the effect of progesterone in primary β-cells. Incubation of RINm5F cells with progesterone increased the number of cells with loss of membrane integrity and DNA fragmentation. Progesterone induced generation of reactive species. Pre-incubation with α-tocopherol attenuated progesterone-induced apoptosis. Western blot analyses revealed increased expression of CREB2 and CHOP in progesterone-treated cells. Progesterone caused apoptotic death of rat islet cells and enhanced generation of reactive species. Our results show that progesterone can be toxic to pancreatic β-cells through an oxidative-stress-dependent mechanism that induces apoptosis. This effect may contribute to the development of GD during pregnancy, particularly under conditions that require administration of pharmacological doses of this hormone.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
HEPES, ≥99.5% (titration)
Sigma-Aldrich
HEPES, BioPerformance Certified, ≥99.5% (titration), suitable for cell culture
Sigma-Aldrich
Propidium iodide, ≥94.0% (HPLC)
Sigma-Aldrich
HEPES buffer solution, 1 M in H2O
Sigma-Aldrich
Propidium iodide solution, solution (1.0 mg/ml in water)
Sigma-Aldrich
Thapsigargin, ≥98% (HPLC), solid film
Sigma-Aldrich
Progesterone, ≥99%
SAFC
HEPES
Supelco
Sodium Citrate, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Progesterone, powder, BioReagent, suitable for cell culture
Sigma-Aldrich
HEPES, BioUltra, for molecular biology, ≥99.5% (T)
Sigma-Aldrich
Propidium iodide, ≥94% (HPLC)
SAFC
HEPES
Sigma-Aldrich
HEPES, BioXtra, pH 5.0-6.5 (1 M in H2O), ≥99.5% (titration)
Sigma-Aldrich
Estriol, ≥97%
Supelco
Progesterone, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
HEPES, BioXtra, suitable for mouse embryo cell culture, ≥99.5% (titration)
Sigma-Aldrich
Citrate Concentrated Solution, BioReagent, suitable for coagulation assays, 4 % (w/v)
Supelco
Progesterone solution, 1.0 mg/mL in acetonitrile, ampule of 1 mL, certified reference material, Cerilliant®
Sigma-Aldrich
HEPES, anhydrous, free-flowing, Redi-Dri, ≥99.5%
Sigma-Aldrich
Progesterone, γ-irradiated, BioXtra, suitable for cell culture
Sigma-Aldrich
Progesterone, meets USP testing specifications
Sigma-Aldrich
Citrate Concentrated Solution, BioUltra, for molecular biology, 1 M in H2O
Supelco
Estriol solution, 1.0 mg/mL in methanol, ampule of 1 mL, certified reference material, Cerilliant®
Supelco
Estriol, VETRANAL®, analytical standard
Supelco
HEPES, Pharmaceutical Secondary Standard; Certified Reference Material
USP
Progesterone, United States Pharmacopeia (USP) Reference Standard
Supelco
Progesterone, VETRANAL®, analytical standard
Sigma-Aldrich
Estriol, meets USP testing specifications
Progesterone for system suitability, European Pharmacopoeia (EP) Reference Standard