transforming-growth-factor-beta and Ocular-Hypertension

To determine the incidence and timing of increased intraocular pressure in eyes with an idiopathic macular hole treated with bovine transforming growth factor-beta 2 (TGF-beta 2) with different intraocular gas concentrations, recombinant TGF-beta 2, or placebo.. Intraocular pressure was measured preoperatively and two days, two weeks, six weeks, and three months postoperatively in two prospective studies of the treatment of idiopathic macular hole with vitrectomy. Group 1 consisted of 95 eyes treated with bovine TGF-beta 2. Eyes in this group were treated with different concentrations of air and perfluoropropane (C3F8) intraocular gas bubbles. Fifteen eyes were treated with air, 15 eyes with 5% perfluoropropane, 15 eyes with 10% perfluoropropane, and 50 eyes with 16% perfluoropropane. Group 2 consisted of 29 eyes treated with recombinant TGF-beta 2. Twenty-six eyes were treated with placebo in a double-masked, randomized, placebo-controlled study evaluating recombinant TGF-beta 2 with a 16% perfluoropropane intraocular gas bubble.. At the two-week examination, the intraocular pressure in Group 1 eyes was > 30 mm Hg in four (26.7%) of 15 eyes treated with air, two (13.3%) of 15 eyes treated with 5% perfluoropropane, one (8.3%) of 12 eyes treated with 10% perfluoropropane, and nine (19.1%) of 47 eyes treated with 16% perfluoropropane. There was no statistically significant difference in the risk of increased intraocular pressure in eyes treated with short-, intermediate-, or long-duration gas tamponade using bovine TGF-beta 2. The intraocular pressure in Group 2 was > 30 mm Hg at the two-week examination in 11 (39.3%) of 28 eyes receiving recombinant TGF-beta 2 compared with one (4.3%) of 23 eyes receiving a placebo (P = .006).. Some eyes develop increased intraocular pressure after vitreous surgery for macular hole, and the increase occurs most frequently between two days and two weeks postoperatively. The risk of increased intraocular pressure is somewhat increased in eyes treated with bovine TGF-beta 2 but is markedly increased in eyes in which recombinant TGF-beta 2 is used as an adjunctive agent for macular hole surgery. Intraocular injection of growth factors produced by similar recombinant DNA techniques may result in potentially dangerous increased intraocular pressure several weeks after surgery. Impurities in the recombinant TGF-beta 2 may explain the relatively high risk of increased intraocular pressure.

Topics: Chemotherapy, Adjuvant; Double-Blind Method; Fluorocarbons; Humans; Incidence; Intraocular Pressure; Ocular Hypertension; Postoperative Complications; Prospective Studies; Recombinant Proteins; Retinal Perforations; Risk Factors; Time Factors; Transforming Growth Factor beta; Vitrectomy

Transforming growth factor beta 2 (TGFβ₂) is often elevated in the aqueous humor (AH) and trabecular meshwork (TM) of patients with primary open-angle glaucoma (POAG) and appears to contribute to POAG pathogenesis. To better understand TGFβ₂ signaling in the eye, TGFβ₂-induced proteomic changes were identified in cells cultured from the TM, a tissue involved in intraocular pressure (IOP) elevation in glaucoma.. Primary cultures of human TM cells from four donors were treated with or without TGFβ₂ (5 ng/mL) for 48 hours; then cellular protein was analyzed by liquid chromatography-mass spectrometry iTRAQ (isobaric tags for relative and absolute quantitation) technology.. A total of 853 proteins were quantified. TGFβ₂ treatment significantly altered the abundance of 47 proteins, 40 of which have not previously been associated with TGFβ₂ signaling in the eye. More than half the 30 elevated proteins support growing evidence that TGFβ₂ induces extracellular matrix remodeling and abnormal cytoskeletal interactions in the TM. The levels of 17 proteins were reduced, including four cytoskeletal and six regulatory proteins. Both elevated and decreased regulatory proteins implicate TGFβ₂-altered processes involving transcription, translation, and the glutamate/glutamine cycle. Altered levels of eight mitochondrial proteins support TGFβ₂-induced mitochondrial dysfunction in the TM that in POAG could contribute to oxidative damage in the AH outflow pathway, TM senescence, and elevated IOP.. The results expand the repertoire of proteins known to participate in TGFβ₂ signaling, provide new molecular insight into POAG, and establish a quantitative proteomics database for the TM that includes candidate glaucoma biomarkers for future validation studies.

Topics: Eye Proteins; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Ocular Hypertension; Peptides; Primary Cell Culture; Protein Precursors; Proteomics; Signal Transduction; Trabecular Meshwork; Transforming Growth Factor beta