title: Influence of methionine oxidation on the aggregation of recombinant human growth hormone.
abstract: Oxidation of methionine (Met) residues is one of the major chemical degradations of therapeutic proteins. This chemical degradation can occur at various stages during production and storage of a biotherapeutic drug. During the oxidation process, the side chain of methionine residue undergoes a chemical modification, with the thioether group substituted by a sulfoxide group. In previous papers, we showed that oxidation of the two most accessible methionine residues of recombinant human growth hormone (r-hGH), Met¹⁴ and Met¹²⁵, has no influence on the conformation of the protein [1]. However, the oxidized r-hGH is less thermally stable than the native protein [2]. In the current work, the consequences of the oxidation of these two methionine residues on the aggregation of r-hGH were investigated. The aggregation properties and kinetics of the native and oxidized r-hGH were measured in different buffers with both spectroscopic and chromatographic methods. Stabilities of oxidized and non-oxidized r-hGH were studied after storage at 37°C and freeze/thawing cycles. Methionine oxidation influenced the aggregation properties of r-hGH. In accelerated stability studies at 37°C, oxidized hormone aggregated more and faster than non-oxidized hormone. In freezing/thawing stability studies, it was found that oxidized r-hGH was less stable than its non-oxidized counterpart. In case of hGH, we have shown that chemical degradations such as oxidation can affect its physical stability and can induce aggregation.
authors: School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland.
authors: Filippo
authors: F
authors: Mulinacci
authors: Emilie
authors: E
authors: Poirier
authors: Martinus A H
authors: MA
authors: Capelle
authors: Robert
authors: R
authors: Gurny
authors: Tudor
authors: T
authors: Arvinte
mesh_terms: D003080:Cold Temperature / Q000009:adverse effects; D004355:Drug Stability; D004356:Drug Storage; D006358:Hot Temperature / Q000009:adverse effects; D019382:Human Growth Hormone / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008715:Methionine / Q000737:chemistry* / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008970:Molecular Weight; D009391:Nephelometry and Turbidimetry; D010084:Oxidation-Reduction; D010316:Particle Size; D011487:Protein Conformation; D011489:Protein Denaturation; D055550:Protein Stability; D011994:Recombinant Proteins / Q000737:chemistry* / Q000378:metabolism; D012995:Solubility; D013050:Spectrometry, Fluorescence
chemical_list: D011994:Recombinant Proteins; D019382:Human Growth Hormone; D008715:Methionine
keywords: 1,8-ANS; 1-anilinonaphthalene-8-sulfonic acid; Aggregation; Freeze/thawing; Human growth hormone; Methionine oxidation; RP-HPLC; RT; SEC; Stability; UV–Vis; r-hGH; recombinant human growth hormone; reverse phase high pressure liquid chromatography; room temperature; size exclusion chromatography; ultraviolet–visible