Biomaterial Database

Interleukin-1 stimulates deoxyribonucleic acid synthesis in immature rat Leydig cells in vitro. 1992

S A Khan, and S J Khan, and J H Dorrington

Banting and Best Department of Medical Research, University of Toronto, Ontario, Canada.

The number of interstitial macrophages in the testis fluctuates according to age, increasing gradually during prepubertal development to reach 15-20% in the interstitial compartment in the adult rat. These macrophages are in close morphological association with Leydig cells. Macrophage products, interleukin-1 (IL-1) and tumor necrosis factor alpha stimulate and/or inhibit steroid production in cultures of Leydig cells. We have studied the effects of macrophage products on DNA synthesis in rat Leydig cells to investigate a possible paracrine role of testicular macrophage products on the proliferation of Leydig cells. Leydig cells isolated from 10-, 20-, and 70-day-old rats were cultured for 48 h in serum-free medium, washed, and treated with different cytokines for 18 h. The medium was then removed, fresh medium containing 0.5 microCi [3H]thymidine was added, and cells were incubated for 4 h prior to determining the incorporation of [3H]thymidine into DNA. Human recombinant IL-1 beta caused a dose-dependent stimulation in the incorporation of [3H]thymidine into DNA in the Leydig cells from 10- and 20-day-old rats but had no effect on DNA synthesis in interstitial cells from adult rats. Maximum stimulation of DNA synthesis in immature Leydig cells was observed with 1-2 ng/ml IL-1 beta. Autoradiography after incubation with [3H]thymidine showed a dramatic increase in the number of labeled Leydig cells after treatment with IL-1 beta (19.27 +/- 3.77% vs. 1.44 +/- 0.52% in control cultures) indicating that IL-1 beta recruited more cells to enter the cell cycle and initiate DNA synthesis. Human recombinant IL-1 alpha and tumor necrosis factor alpha also caused significant stimulation of DNA synthesis in Leydig cells but these cytokines were much less potent (1-10%) than IL-1 beta. IL-1 beta enhanced the effects of maximally effective concentrations of growth-promoting agents previously known to stimulate DNA synthesis in immature rat Leydig cells, i.e. human CG, steroidogenesis-inducing protein, and transforming growth factor alpha plus insulin. On the basis of these results it is concluded that IL-1 may play an important role in the proliferation of Leydig cells during prepubertal development in immature rats.

UI	MeSH Term	Description	Entries
D007375	Interleukin-1	A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.	IL-1,Lymphocyte-Activating Factor,Epidermal Cell Derived Thymocyte-Activating Factor,Interleukin I,Macrophage Cell Factor,T Helper Factor,Epidermal Cell Derived Thymocyte Activating Factor,Interleukin 1,Lymphocyte Activating Factor
D007985	Leydig Cells	Steroid-producing cells in the interstitial tissue of the TESTIS. They are under the regulation of PITUITARY HORMONES; LUTEINIZING HORMONE; or interstitial cell-stimulating hormone. TESTOSTERONE is the major androgen (ANDROGENS) produced.	Interstitial Cells, Testicular,Leydig Cell,Testicular Interstitial Cell,Testicular Interstitial Cells,Cell, Leydig,Cell, Testicular Interstitial,Cells, Leydig,Cells, Testicular Interstitial,Interstitial Cell, Testicular
D008297	Male		Males
D002452	Cell Count	The number of CELLS of a specific kind, usually measured per unit volume or area of sample.	Cell Density,Cell Number,Cell Counts,Cell Densities,Cell Numbers,Count, Cell,Counts, Cell,Densities, Cell,Density, Cell,Number, Cell,Numbers, Cell
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D001345	Autoradiography	The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)	Radioautography
D014409	Tumor Necrosis Factor-alpha	Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.	Cachectin,TNF-alpha,Tumor Necrosis Factor Ligand Superfamily Member 2,Cachectin-Tumor Necrosis Factor,TNF Superfamily, Member 2,TNFalpha,Tumor Necrosis Factor,Cachectin Tumor Necrosis Factor,Tumor Necrosis Factor alpha