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Höybye C. Comparing treatment with daily and long-acting growth hormone formulations in adults with growth hormone deficiency: Challenging issues, benefits, and risks. Best Pract Res Clin Endocrinol Metab 2023; 37:101788. [PMID: 37308376 DOI: 10.1016/j.beem.2023.101788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Daily administration of growth hormone (GH) treatment has been in clinical use for treatment for GH deficiency (GHD) in adults for more than 30 years. Numerous studies have demonstrated evidence that GH treatment improves body composition, cardiovascular risk factors and quality of life with few side effects. Less frequent GH injections are hypothesized to improve adherence and several long-acting GH (LAGH) formulations have been developed and a few have been approved and marketed. Different pharmacological modifications have been applied and the pharmacokinetics and pharmacodynamics of LAGH are different to each other and to those of daily injections and require different dosing and monitoring specific for each LAGH. Studies have shown improved adherence with LAGH, and short-term efficacy and side effects are comparable between daily GH injections and LAGHs. Long-term treatment with daily GH injections is effective and safe, while long-term studies for LAGHs are awaited. In this review challenges, benefits, and risks of treatment with daily and long-acting GH preparations will be compared.
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Affiliation(s)
- Charlotte Höybye
- Department of Endocrinology and Department of Molecular Medicine and Surgery, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
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2
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Mastromauro C, Giannini C, Chiarelli F. Short stature related to Growth Hormone Insensitivity (GHI) in childhood. Front Endocrinol (Lausanne) 2023; 14:1141039. [PMID: 37008935 PMCID: PMC10050683 DOI: 10.3389/fendo.2023.1141039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/20/2023] [Indexed: 03/17/2023] Open
Abstract
Linear growth during childhood is the result of the synergic contribution of different factors. The best growth determinant system during each period of life is represented by the growth hormone-insulin-like growth factor axis (GH-IGF), even if several other factors are involved in normal growth. Within the broad spectrum of growth disorders, an increased importance has been placed on growth hormone insensitivity (GHI). GHI was reported for the first time by Laron as a syndrome characterized by short stature due to GH receptor (GHR) mutation. To date, it is recognized that GHI represents a wide diagnostic category, including a broad spectrum of defects. The peculiar characteristic of GHI is the low IGF-1 levels associated with normal or elevated GH levels and the lack of IGF-1 response after GH administration. Recombinant IGF-1 preparations may be used in the treatment of these patients.
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Affiliation(s)
| | - Cosimo Giannini
- Department of Pediatrics, University of Chieti, Chieti, Italy
- Center of Advanced Studies and Technology – CAST (ex CesSI-MeT), University of Chieti, Chieti, Italy
| | - Francesco Chiarelli
- Department of Pediatrics, University of Chieti, Chieti, Italy
- Center of Advanced Studies and Technology – CAST (ex CesSI-MeT), University of Chieti, Chieti, Italy
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3
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Rigi G, Rostami A, Ghomi H, Ahmadian G, Mirbagheri VS, Jeiranikhameneh M, Vahed M, Rahimi S. Optimization of expression, purification and secretion of functional recombinant human growth hormone in Escherichia coli using modified staphylococcal protein a signal peptide. BMC Biotechnol 2021; 21:51. [PMID: 34399745 PMCID: PMC8369807 DOI: 10.1186/s12896-021-00701-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/10/2021] [Indexed: 11/10/2022] Open
Abstract
Background Human Growth Hormone (hGH) is a glycoprotein released from the pituitary gland. Due to the wide range of effects in humans, any disruption in hGH secretion could have serious consequences. This highlights the clinical importance of hGH production in the treatment of different diseases associated with a deficiency of this hormone. The production of recombinant mature hormone in suitable hosts and secretion of this therapeutic protein into the extracellular space can be considered as one of the best cost-effective approaches not only to obtain the active form of the protein but also endotoxin-free preparation. Since the natural growth hormone signal peptide is of eukaryotic origin and is not detectable by any of the Escherichia coli secretory systems, including Sec and Tat, and is therefore unable to secrete hGH in the prokaryotic systems, designing a new and efficient signal peptide is essential to direct hGh to the extracellular space. Results In this study, using a combination of the bioinformatics design and molecular genetics, the protein A signal peptide from Staphylococcus aureus was modified, redesigned and then fused to the mature hGH coding region. The recombinant hGH was then expressed in E. coli and successfully secreted to the medium through the Sec pathway. Secretion of the hGH into the medium was verified using SDS-PAGE and western blot analysis. Recombinant hGH was then expressed in E. coli and successfully secreted into cell culture medium via the Sec pathway. The secretion of hGH into the extracellular medium was confirmed by SDS-PAGE and Western blot analysis. Furthermore, the addition of glycine was shown to improve hGH secretion onto the culture medium. Equations for determining the optimal conditions were also determined. Functional hGH analysis using an ELISA-based method confirmed that the ratio of the active form of secreted hGH to the inactive form in the periplasm is higher than this ratio in the cytoplasm. Conclusions Since the native signal protein peptide of S. aureus protein A was not able to deliver hGH to the extracellular space, it was modified using bioinformatics tools and fused to the n-terminal region of hGh to show that the redesigned signal peptide was functional. Supplementary Information The online version contains supplementary material available at 10.1186/s12896-021-00701-x.
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Affiliation(s)
- Garshasb Rigi
- Department of Genetics, Faculty of Basic Science, Shahrekord University, P. O. Box 115, Shahrekord, 881 863 4141, Iran.,Department of Industrial Biotechnology, Research Institute of Biotechnology, Shahrekord University, Shahrekord, Iran
| | - Amin Rostami
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Habib Ghomi
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Gholamreza Ahmadian
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
| | - Vasiqe Sadat Mirbagheri
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.,Fisheries products processing group, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
| | - Meisam Jeiranikhameneh
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Majid Vahed
- Pharmaceutical Sciences Research Center, Shahid Beheshti University of Medical Sciences, Niayesh Highway, Valiasr Ave, Tehran, Iran.,Department of Toxico/Pharmacology, School of Pharmacy, Shahid Beheshti, University of Medical Sciences, Niayesh Highway, Valiasr Ave, Tehran, Iran
| | - Sahel Rahimi
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
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4
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Yuen KCJ, Miller BS, Boguszewski CL, Hoffman AR. Usefulness and Potential Pitfalls of Long-Acting Growth Hormone Analogs. Front Endocrinol (Lausanne) 2021; 12:637209. [PMID: 33716988 PMCID: PMC7943875 DOI: 10.3389/fendo.2021.637209] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 01/11/2021] [Indexed: 11/18/2022] Open
Abstract
Daily recombinant human GH (rhGH) is currently approved for use in children and adults with GH deficiency (GHD) in many countries with relatively few side-effects. Nevertheless, daily injections can be painful and distressing for some patients, often resulting in non-adherence and reduction of treatment outcomes. This has prompted the development of numerous long-acting GH (LAGH) analogs that allow for decreased injection frequency, ranging from weekly, bi-weekly to monthly. These LAGH analogs are attractive as they may theoretically offer increased patient acceptance, tolerability, and therapeutic flexibility. Conversely, there may also be pitfalls to these LAGH analogs, including an unphysiological GH profile and differing molecular structures that pose potential clinical issues in terms of dose initiation, therapeutic monitoring, incidence and duration of side-effects, and long-term safety. Furthermore, fluctuations of peak and trough serum GH and IGF-I levels and variations in therapeutic efficacy may depend on the technology used to prolong GH action. Previous studies of some LAGH analogs have demonstrated non-inferiority compared to daily rhGH in terms of increased growth velocity and improved body composition in children and adults with GHD, respectively, with no significant unanticipated adverse events. Currently, two LAGH analogs are marketed in Asia, one recently approved in the United States, another previously approved but not marketed in Europe, and several others proceeding through various stages of clinical development. Nevertheless, several practical questions still remain, including possible differences in dose initiation between naïve and switch-over patients, methodology of dose adjustment/s, timing of measuring serum IGF-I levels, safety, durability of efficacy and cost-effectiveness. Long-term surveillance of safety and efficacy of LAGH analogs are needed to answer these important questions.
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Affiliation(s)
- Kevin C. J. Yuen
- Barrow Pituitary Center, Barrow Neurological Institute, Departments of Neuroendocrinology and Neurosurgery, University of Arizona College of Medicine and Creighton School of Medicine, Phoenix, AZ, United States
- *Correspondence: Kevin C. J. Yuen,
| | - Bradley S. Miller
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States
| | - Cesar L. Boguszewski
- SEMPR, Serviço de Endocrinologia e Metabologia, Departamento de Clínica Médica, Hospital de Clínicas da Universidade Federal do Paraná, Curitiba, Brazil
| | - Andrew R. Hoffman
- Department of Medicine, VA Palo Alto Health Care System and Stanford University School of Medicine, Palo Alto, CA, United States
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Miller BS, Velazquez E, Yuen KCJ. Long-Acting Growth Hormone Preparations - Current Status and Future Considerations. J Clin Endocrinol Metab 2020; 105:5611083. [PMID: 31676901 PMCID: PMC7755139 DOI: 10.1210/clinem/dgz149] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/30/2019] [Indexed: 12/30/2022]
Abstract
CONTEXT Long-acting GH (LAGH) preparations are currently being developed in an attempt to improve adherence. The profile of GH action following administration of LAGH raises practical questions about clinical monitoring and long-term safety and efficacy of these new therapeutic agents. METHODS Recent literature and meeting proceedings regarding LAGH preparations are reviewed. RESULTS Multiple LAGH preparations are currently at various stages of development, allowing for decreased GH injection frequency from daily to weekly, biweekly, or monthly. Following administration of LAGH, the serum peak and trough GH and IGF-I levels vary depending upon the mechanism used to prolong GH action. Randomized, controlled clinical trials of some LAGH preparations have reported non-inferiority compared with daily recombinant human GH (rhGH) for improved growth velocity and body composition in children and adults with GH deficiency (GHD), respectively. No significant LAGH-related adverse events have been reported during short-term therapy. CONCLUSION Multiple LAGH preparations are proceeding through clinical development with some showing promising evidence of short-term clinical efficacy and safety in children and adults with GHD. The relationship of transient elevations of GH and IGF-I following administration of LAGH to efficacy and safety remain to be elucidated. For LAGH to replace daily rhGH in the treatment of individuals with GHD, a number of practical questions need to be addressed including methods of dose adjustment, timing of monitoring of IGF-I, safety, efficacy, and cost-effectiveness. Long-term surveillance of efficacy and safety of LAGH preparations will be needed to answer these clinically relevant questions.
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Affiliation(s)
- Bradley S Miller
- Division of Endocrinology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
- Correspondence and Reprint Requests: Bradley S. Miller, MD, PhD, 8952D, MB671 East Bldg, Division of Endocrinology, Department of Pediatrics, University of Minnesota, 2450 Riverside Avenue, Minneapolis, MN 55454. E-mail:
| | - Eric Velazquez
- Division of Endocrinology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
| | - Kevin C J Yuen
- Departments of Neuroendocrinology and Neurosurgery, Barrow Pituitary Center, Barrow Neurological Institute, University of Arizona College of Medicine, Phoenix, Arizona
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6
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Binder G, Heidenreich L, Schnabel D, Dunstheimer D, Oeverink R, Kiess W, Körner A, Kratzsch J. Biological Significance of Anti-GH Antibodies in Children Treated with rhGH. Horm Res Paediatr 2019; 91:17-24. [PMID: 30947197 DOI: 10.1159/000497409] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/31/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The occurrence of antidrug antibodies is common in children treated with recombinant human growth hormone (rhGH). However, their clinical significance is unclear. OBJECTIVE This study aimed to examine the clinical significance of anti-GH antibodies by analyzing the phenotype of patients who tested positive in relation to the quantity of anti-GH antibodies. METHOD In this laboratory-based retrospective study encompassing a time span of 6 years, all positive samples were identified, and senders were contacted. Anti-GH antibodies were measured using a radioprecipitation assay; positive samples underwent a confirmatory assay. RESULTS Out of a total of 104 samples from 66 patients, positive test results were found in 28 samples from 13 patients. Clinical data were available from all but one. The group with positive test results comprised 6 patients with a normal response to GH provocative tests (group A) and 6 with an insufficient response or with isolated GH deficiency (IGHD) type 1A (group B). Diagnoses in group A were neurosecretory dysfunction, bioinactive GH syndrome and constitutional delay of growth and puberty. Diagnoses in group B were IGHD type 1A, septo-optic dysplasia, and cerebral midline defect with multiple pituitary hormone deficiency. Insufficient growth response to rhGH was absent except in one sibling pair with IGHD type 1A and a patient with cerebral midline defect. These patients had the highest concentrations of anti-GH antibodies. CONCLUSIONS The biological significance of anti-GH antibodies seems to be limited to patients with high concentrations of anti-GH antibodies. For all other patients, we recommend a careful "wait and see" strategy and monitoring antibody titers.
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Affiliation(s)
- Gerhard Binder
- Pediatric Endocrinology, University Children's Hospital, Tübingen, Germany,
| | - Laura Heidenreich
- Pediatric Endocrinology, University Children's Hospital, Tübingen, Germany
| | - Dirk Schnabel
- Pediatric Endocrinology, Charité, University Medicine, Berlin, Germany
| | | | | | - Wieland Kiess
- University Hospital for Children and Adolescents, Leipzig, Germany
| | - Antje Körner
- University Hospital for Children and Adolescents, Leipzig, Germany
| | - Jürgen Kratzsch
- Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University of Leipzig, Leipzig, Germany
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7
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Abstract
Recombinant human growth hormone (rhGH) has been in clinical use for more than 30 years. With the expiration of patent exclusivity for the first wave of rhGH products and other biopharmaceuticals, the opportunity emerged for the development of biosimilar medicines. A biosimilar is defined by the European Medicines Agency (EMA) as a biological medicine that is similar to another biological medicine that has already been authorized for use. The EMA led the way (well ahead of the Food and Drug Administration in the US) in developing the biosimilar concept, and the type of science-based regulatory framework required to ensure high-quality, safe, and effective biosimilar medicines; the provisions for approval of biosimilars have been in place in Europe since 2005. Under these provisions, Omnitrope® was approved by the EMA in 2006 as the world's first biosimilar medicine; 2016 therefore marks the 10th anniversary of its approval in Europe. A substantial data set, based on clinical development studies and 10 years of postapproval use, has now accumulated for biosimilar rhGH; this data set shows that the product is an effective treatment option for children who require rhGH treatment, and has a safety profile that is consistent with the rhGH class. The decade since the EMA approved biosimilar rhGH has seen the successful approval and clinical use of 20 biosimilar medicines, confirming the integrity of the scientific basis for the biosimilar concept, as well as the quality of regulatory decision-making.
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Affiliation(s)
- Paul Saenger
- Division of Pediatric Endocrinology, Department of Pediatrics, Winthrop University Hospital, Mineola, NY, USA
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8
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Borrás Pérez MV, Kriström B, Romer T, Walczak M, Höbel N, Zabransky M. Ten years of clinical experience with biosimilar human growth hormone: a review of safety data. DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:1497-1503. [PMID: 28553080 PMCID: PMC5439985 DOI: 10.2147/dddt.s130909] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Safety concerns for recombinant human growth hormone (rhGH) treatments include impact on cancer risk, impact on glucose homeostasis, and the formation of antibodies to endogenous/exogenous GH. Omnitrope® (biosimilar rhGH) was approved by the European Medicines Agency in 2006, with approval granted on the basis of comparable quality, safety, and efficacy to the reference medicine (Genotropin®). Additional concerns that may exist in relation to biosimilar rhGH include safety in indications granted on the basis of extrapolation and the impact of changing to biosimilar rhGH from other rhGH treatments. A substantial data set is available to fully understand the safety profile of biosimilar rhGH, which includes data from its clinical development studies and 10 years of post-approval experience. As of June 2016, 106,941,419 patient days (292,790 patient-years) experience has been gathered for biosimilar rhGH. Based on the available data, there have been no unexpected or unique adverse events related to biosimilar rhGH treatment. There is no increased risk of cancer, adverse glucose homeostasis, or immunogenic response with biosimilar rhGH compared with the reference medicine and other rhGH products. The immunogenicity of biosimilar rhGH is also similar to that of the reference and other rhGH products. Physicians should be reassured that rhGH products have a good safety record when used for approved indications and at recommended doses, and that the safety profile of biosimilar rhGH is in keeping with that of other rhGH products.
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Affiliation(s)
| | - Berit Kriström
- Department of Clinical Sciences, Pediatrics, Umeå University, Umeå, Sweden
| | - Tomasz Romer
- Department of Endocrinology, Children's Health Research Institute, Warsaw
| | - Mieczyslaw Walczak
- Department of Paediatric Endocrinology and Diabetology, Pomeranian Medical University, Szczecin, Poland
| | - Nadja Höbel
- Sandoz Biopharmaceuticals, Hexal AG, Holzkirchen, Germany
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9
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Chisholm CF, Baker AE, Soucie KR, Torres RM, Carpenter JF, Randolph TW. Silicone Oil Microdroplets Can Induce Antibody Responses Against Recombinant Murine Growth Hormone in Mice. J Pharm Sci 2016; 105:1623-1632. [PMID: 27020987 PMCID: PMC4846524 DOI: 10.1016/j.xphs.2016.02.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 02/18/2016] [Accepted: 02/19/2016] [Indexed: 01/09/2023]
Abstract
Therapeutic protein products can cause adverse immune responses in patients. The presence of subvisible particles is a potential contributing factor to the immunogenicity of parenterally administered therapeutic protein formulations. Silicone oil microdroplets, which derive from silicone oil used as a lubricating coating on barrels of prefilled glass syringes, are often found in formulations. In this study, we investigated the potential of silicone oil microdroplets to act as adjuvants to induce an immune response in mice against a recombinant murine protein. Antibody responses in mice to subcutaneous injections of formulations of recombinant murine growth hormone (rmGH) that contained silicone oil microdroplets were measured and compared to responses to oil-free rmGH formulations. When rmGH formulations containing silicone oil microdroplets were administered once every other week, anti-rmGH antibodies were not detected. In contrast, mice exhibited a small IgG1 response against rmGH when silicone oil-containing rmGH formulations were administered daily, and an anti-rmGH IgM response was observed at later time points. Our findings showed that silicone oil microdroplets can act as an adjuvant to promote a break in immunological tolerance and induce antibody responses against a recombinant self-protein.
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Affiliation(s)
- Carly Fleagle Chisholm
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309
| | - Abby E Baker
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309
| | - Kaitlin R Soucie
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309
| | - Raul M Torres
- Department of Immunology & Microbiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - John F Carpenter
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045
| | - Theodore W Randolph
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309.
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10
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Gan EH, MacArthur K, Mitchell AL, Joshi A, Crock P, Pearce SHS. Spontaneous and tetracosactide-induced anti-ACTH antibodies in man. Clin Endocrinol (Oxf) 2016; 84:489-95. [PMID: 25880719 PMCID: PMC4949547 DOI: 10.1111/cen.12795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 03/04/2015] [Accepted: 04/10/2015] [Indexed: 11/30/2022]
Abstract
CONTEXT During a clinical trial of regular tetracosactide depot injections, four of 13 patients with autoimmune Addison's disease (AAD) developed adverse reactions immediately following tetracosactide injections. We wished to investigate whether these adverse effects could be due to the production of circulating antitetracosactide (ACTH1-24 ) antibodies. DESIGN Anti-ACTH binding activity was investigated using immunoblotting and ELISA on sera from participants in the trial (n = 13; baseline and after tetracosactide exposure), 131 unrelated patients with AAD, 92 patients with Graves' disease (GD), 15 patients with isolated ACTH deficiency and 102 controls. Immunohistochemistry of human pituitary tissue sections was also performed using pooled sera. RESULTS Bands at approximately 4 and 6 kDa, corresponding to ACTH1-24 and full-length ACTH1-39, respectively, were found in 10 of 13 (77%) of sera from trial patients exposed to tetracosactide, including all those who had an adverse reaction. This is in contrast with healthy control sera, which showed no binding. The same 10 subjects also showed high levels of binding to tetracosactide by ELISA, along with 21% of patients with AAD, 14% of patients with GD (both P < 0·001 compared to controls) and 1 isolated ACTH deficiency patient (7% of 15). These sera also recognized native ACTH in human pituitary sections. CONCLUSION Our study demonstrates that repeated administration of depot tetracosactide can lead to anti-ACTH1-24 autoreactivity. In addition, a significant number of patients with AAD and GD also had similar, spontaneous, anti-ACTH reactivity. The presence of these antibodies could mediate some of the adverse effects or explain the well-described phenomenon of resistance to chronic ACTH therapy.
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Affiliation(s)
- Earn H. Gan
- Institute of Genetic MedicineNewcastle UniversityNewcastle upon TyneUK
- Endocrine UnitRoyal Victoria InfirmaryNewcastle upon TyneUK
| | - Katie MacArthur
- Institute of Genetic MedicineNewcastle UniversityNewcastle upon TyneUK
| | - Anna L. Mitchell
- Institute of Genetic MedicineNewcastle UniversityNewcastle upon TyneUK
- Endocrine UnitRoyal Victoria InfirmaryNewcastle upon TyneUK
| | - Abhijit Joshi
- Cellular Pathology DepartmentRoyal Victoria InfirmaryNewcastle upon TyneUK
| | - Patricia Crock
- John Hunter Children's HospitalUniversity of NewcastleNewcastleNSWAustralia
| | - Simon H. S. Pearce
- Institute of Genetic MedicineNewcastle UniversityNewcastle upon TyneUK
- Endocrine UnitRoyal Victoria InfirmaryNewcastle upon TyneUK
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Kurtoğlu S, Hatipoglu N. Growth hormone insensitivity: diagnostic and therapeutic approaches. J Endocrinol Invest 2016; 39:19-28. [PMID: 26062520 DOI: 10.1007/s40618-015-0327-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Accepted: 05/21/2015] [Indexed: 01/17/2023]
Abstract
INTRODUCTION Growth hormone resistance defines several genetic (primary) and acquired (secondary) pathologies that result in completely or partially interrupted activity of growth hormone. An archetypal disease of this group is the Laron-type dwarfism caused by mutations in growth hormone receptors. The diagnosis is based on high basal levels of growth hormone, low insulin like growth factor-I (IGF-1) level, unresponsiveness to IGF generation test and genetic testing. Recombinant IGF-1 preparations are used in the treatment CONCLUSION In this article, clinical characteristics, diagnosis and therapeutic approaches of the genetic and other diseases leading to growth hormone insensitivity are reviewed.
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Affiliation(s)
- S Kurtoğlu
- Department of Pediatric Endocrinology, Medical Faculty, Erciyes University, 38039, Kayseri, Turkey
| | - N Hatipoglu
- Department of Pediatric Endocrinology, Medical Faculty, Erciyes University, 38039, Kayseri, Turkey.
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12
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Kononova NV, Iakovlev AV, Zhuravko AM, Pankeev NN, Minaev SV, Bobruskin AI, Mart'ianov VA. [Recombinant granulocyte-colony stimulating factor (filgrastim): optimization of conditions of isolation and purification from inclusion body]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2015; 40:550-9. [PMID: 25895350 DOI: 10.1134/s1068162014050161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We developed a unified process platform for two recombinant human GCSF medicines--one with the non-prolonged and the other with prolonged action. This unified technology led to a simpler and cheaper production while introduction of the additional pegylation stage to the technological line eased obtaining of the medicines with different action and allowed to standardize technological process documenting according to GMP requirements.
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13
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Liu R, Ma D, Li Y, Hu R, Peng Y, Wang Q. The anorexic effect of Ex4/Fc through GLP-1 receptor activation in high-fat diet fed mice. Acta Biochim Biophys Sin (Shanghai) 2014; 46:675-81. [PMID: 24951724 DOI: 10.1093/abbs/gmu044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Exendin-4 (Ex4), a peptide initially found in the saliva of the Gila monster, can activate the signaling pathway of the incretin hormone glucagon-like peptide-1 (GLP-1) through the GLP-1 receptor (GLP-1R). We previously reported that a chimera protein consisting of Ex4 and mouse IgG heavy chain constant regions (Ex4/Fc) can exert biological effects of GLP-1, such as improving glycemic control and ameliorating manifestations in diabetic mice. The aim of this study was to determine whether Ex4/Fc is effective in modulating energy homeostasis in mice. Our results showed that in vivo expression of Ex4/Fc by intramuscular injection of the plasmid encoding Ex4/Fc followed by local electroporation effectively decreased food intake in the mice on high-fat diet (HFD) feeding. In addition, the reduced energy intake was associated with the decreased excrements from the Ex4/Fc-treated HFD mice but not the Fc control mice. Remarkably, the Ex4/Fctreated HFD mice displayed significantly lower triglyceride (TG) levels when compared with the control mice. Interestingly, while the leptin levels were not changed, the circulating ghrelin levels were higher in Ex4/Fc mice than those in the Fc control mice. These results suggested that Ex4/Fc can improve energy metabolism and lipid metabolism through GLP-1R in mice under excessive nutrition conditions.
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14
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Liang Y, Qiu H, Glinka Y, Lazarus AH, Ni H, Prud'homme GJ, Wang Q. Immunity against a therapeutic xenoprotein/Fc construct delivered by gene transfer is reduced through binding to the inhibitory receptor FcγRIIb. J Gene Med 2011; 13:470-7. [DOI: 10.1002/jgm.1598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Affiliation(s)
- Yaming Liang
- Division of Endocrinology and Metabolism, the Keenan Research Centre in the Li Ka Shing Knowledge Institute; St Michael's Hospital; Toronto; Ontario; Canada
| | - Hongmin Qiu
- Division of Endocrinology and Metabolism, the Keenan Research Centre in the Li Ka Shing Knowledge Institute; St Michael's Hospital; Toronto; Ontario; Canada
| | - Yelena Glinka
- Department of Laboratory Medicine & Pathobiology; University of Toronto; Toronto; Ontario; Canada
| | - Alan H. Lazarus
- Department of Laboratory Medicine & Pathobiology; University of Toronto; Toronto; Ontario; Canada
| | - Heyu Ni
- Department of Laboratory Medicine & Pathobiology; University of Toronto; Toronto; Ontario; Canada
| | - Gerald J. Prud'homme
- Department of Laboratory Medicine & Pathobiology; University of Toronto; Toronto; Ontario; Canada
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15
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Wang Q, Chen K, Liu R, Zhao F, Gupta S, Zhang N, Prud'homme GJ. Novel GLP-1 fusion chimera as potent long acting GLP-1 receptor agonist. PLoS One 2010; 5:e12734. [PMID: 20856794 PMCID: PMC2939854 DOI: 10.1371/journal.pone.0012734] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2010] [Accepted: 08/13/2010] [Indexed: 01/11/2023] Open
Abstract
GLP-1 has a variety of anti-diabetic effects. However, native GLP-1 is not suitable for therapy of diabetes due to its short half-life (t1/2<2 min). To circumvent this, we developed a long-lasting GLP-1 receptor agonist by the fusion of GLP-1 with human IgG2 Fc (GLP-1/hIgG2). ELISA-based receptor binding assay demonstrated that GLP-1/hIgG2 had high binding affinity to the GLP-1R in INS-1 cells (Kd = 13.90±1.52 nM). Upon binding, GLP-1/hIgG2 was rapidly internalized by INS-1 cells in a dynamin-dependent manner. Insulin RIA showed that GLP-1/IgG2 dose-dependently stimulated insulin secretion from INS-1 cells. Pharmacokinetic studies in CD1 mice showed that with intraperitoneal injection (i.p.), the GLP-1/hIgG2 peaked at 30 minutes in circulation and maintained a plateau for >168 h. Intraperitoneal glucose tolerance test (IPGTT) in mice showed that GLP-1/hIgG2 significantly decreased glucose excursion. Furthermore, IPGTT performed on mice one week after a single drug-injection also displayed significantly reduced glucose excursion, indicating that GLP-1/hIgG2 fusion protein has long-lasting effects on the modulation of glucose homeostasis. GLP-1/hIgG2 was found to be effective in reducing the incidence of diabetes in multiple-low-dose streptozotocin-induced type 1 diabetes in mice. Together, the long-lasting bioactive GLP-1/hIgG2 retains native GLP-1 activities and thus may serve as a potent GLP-1 receptor agonist.
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Affiliation(s)
- Qinghua Wang
- Division of Endocrinology and Metabolism, the Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.
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16
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Singh SK. Impact of product-related factors on immunogenicity of biotherapeutics. J Pharm Sci 2010; 100:354-87. [PMID: 20740683 DOI: 10.1002/jps.22276] [Citation(s) in RCA: 250] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 05/13/2010] [Accepted: 05/24/2010] [Indexed: 12/12/2022]
Abstract
All protein therapeutics have the potential to be immunogenic. Several factors, including patient characteristics, disease state, and the therapy itself, influence the generation of an immune response. Product-related factors such as the molecule design, the expression system, post-translational modifications, impurities, contaminants, formulation and excipients, container, closure, as well as degradation products are all implicated. However, a critical examination of the available data shows that clear unequivocal evidence for the impact of these latter factors on clinical immunogenicity is lacking. No report could be found that clearly deconvolutes the clinical impact of the product attributes on patient susceptibility. Aggregation carries the greatest concern as a risk factor for immunogenicity, but the impact of aggregates is likely to depend on their structure as well as on the functionality (e.g., immunostimulatory or immunomodulatory) of the therapeutic. Preclinical studies are not yet capable of assessing the clinically relevant immunogenicity potential of these product-related factors. Simply addressing these risk factors as part of product development will not eliminate immunogenicity. Minimization of immunogenicity has to begin at the molecule design stage by reducing or eliminating antigenic epitopes and building in favorable physical and chemical properties.
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Affiliation(s)
- Satish Kumar Singh
- Pfizer, Inc., BioTherapeutics Pharmaceutical Sciences, Pharmaceutical Research and Development, Chesterfield, Missouri 63017, USA.
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17
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Beltrand J, Lahlou N, Le Charpentier T, Sebag G, Leka S, Polak M, Tubiana-Rufi N, Lacombe D, de Kerdanet M, Huet F, Robert JJ, Chevenne D, Gressens P, Lévy-Marchal C. Resistance to leptin-replacement therapy in Berardinelli-Seip congenital lipodystrophy: an immunological origin. Eur J Endocrinol 2010; 162:1083-91. [PMID: 20236991 DOI: 10.1530/eje-09-1027] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
CONTEXT Recently, in a 4-month proof-of-concept trial, beneficial metabolic effects were reported in non-diabetic children with Berardinelli-Seip congenital lipodystrophy (BSCL); this information prompted us to hypothesize that long-term leptin-replacement therapy might improve or reverse the early complications of the disease in these patients. PATIENTS AND METHODS A 28-month trial was implemented in eight patients. Efficacy assessment was based on a decrease in serum triglyceride concentrations, and/or a decrease in liver volume and/or an increase in insulin sensitivity of at least 30% respectively. The response was defined as follows: total (3/3 positive criteria), partial (1 or 2/3), or negative (0/3). Anti-leptin antibodies were measured with a radiobinding assay, and a neutralizing effect was assessed in primary cultures of embryonic neurons incubated with an apoptotic agent (N-methyl-D-aspartate) and the patient serum, with or without leptin. RESULTS A negative or partial response to treatment was observed in five of eight patients even when leptin dosages were increased. A displaceable leptin binding was detectable in all patients after 2 months of treatment. At 28 months, binding was higher in the patients with a negative response than in the total responders, and it paralleled both the increase in leptin dosage and serum leptin concentrations. Co-incubation of embryonic neurons with serum from two patients with a negative response inhibited the neuroprotective effect of leptin. CONCLUSION Under leptin therapy, patients with BSCL may develop a resistance to leptin, which could be partly of immunological origin, blunting the previously reported beneficial effects.
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Affiliation(s)
- Jacques Beltrand
- Unité INSERM U690, Hôpital Robert Debré, 48 Boulevard Sérurier, Paris, France.
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18
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Ye H, Hill J, Kauffman J, Han X. Qualitative and quantitative comparison of brand name and generic protein pharmaceuticals using isotope tags for relative and absolute quantification and matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry. Anal Biochem 2010; 400:46-55. [DOI: 10.1016/j.ab.2010.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 12/07/2009] [Accepted: 01/07/2010] [Indexed: 11/30/2022]
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19
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Fradkin AH, Boand CS, Eisenberg SP, Rosendahl MS, Randolph TW. Recombinant murine growth hormone from E. coli inclusion bodies: Expression, high-pressure solubilization and refolding, and characterization of activity and structure. Biotechnol Prog 2010; 26:743-9. [DOI: 10.1002/btpr.393] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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20
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Kausaite-Minkstimiene A, Ramanaviciene A, Ramanavicius A. Surface plasmon resonance biosensor for direct detection of antibodies against human growth hormone. Analyst 2009; 134:2051-7. [DOI: 10.1039/b907315a] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Wang J, Lozier J, Johnson G, Kirshner S, Verthelyi D, Pariser A, Shores E, Rosenberg A. Neutralizing antibodies to therapeutic enzymes: considerations for testing, prevention and treatment. Nat Biotechnol 2008; 26:901-8. [PMID: 18688246 PMCID: PMC3478093 DOI: 10.1038/nbt.1484] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Lysosomal storage diseases are characterized by deficiencies in lysosomal enzymes, allowing accumulation of target substrate in cells and eventually causing cell death. Enzyme replacement therapy is the principal treatment for most of these diseases. However, these therapies are often complicated by immune responses to the enzymes, blocking efficacy and causing severe adverse outcomes by neutralizing product activity. It is thus crucial to understand the relationships between genetic mutations, endogenous residual enzyme proteins (cross-reactive immunologic material), development of neutralizing antibodies and their impact on clinical outcomes of lysosomal storage diseases. For patients in whom neutralizing antibodies may cause severe adverse clinical outcomes, it is paramount to develop tolerance inducing protocols to preclude, where predictable, or treat such life-threatening responses.
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Affiliation(s)
- Jinhai Wang
- Division of Therapeutic Proteins, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, NIH Building 29B, 8800 Rockville Pike, Bethesda, Maryland 20892, USA
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22
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Bailly-Chouriberry L, Chu-Van E, Pinel G, Garcia P, Popot MA, André-Fontaine G, Bonnaire Y, Le Bizec B. Detection of secondary biomarker of met-eGH as a strategy to screen for somatotropin misuse in horseracing. Analyst 2008; 133:270-6. [DOI: 10.1039/b713712e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Kumar M, Hunag Y, Glinka Y, Prud'homme GJ, Wang Q. Gene therapy of diabetes using a novel GLP-1/IgG1-Fc fusion construct normalizes glucose levels in db/db mice. Gene Ther 2006; 14:162-72. [PMID: 16943856 DOI: 10.1038/sj.gt.3302836] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Glucagon-like peptide (GLP-1), a major physiological incretin, plays numerous important roles in modulating blood glucose homeostasis and has been proposed for the treatment of type 2 diabetes. The major obstacles for using native GLP-1 as a therapeutic agent are that it must be delivered by a parenteral route and has a short half-life. In an attempt to develop a strategy to prolong the physiological t(1/2) and enhance the potency of GLP-1, a fusion protein consisting of active human GLP-1 and mouse IgG(1) heavy chain constant regions (GLP-1/Fc) was generated. A plasmid encoding an IgK leader peptide-driven secretable fusion protein of the active GLP-1 and IgG(1)-Fc was constructed for mammalian expression. This plasmid allows for expression of bivalent GLP-1 peptide ligands as a result of IgG-Fc homodimerization. In vitro studies employing purified GLP-1/Fc indicate that the fusion protein is functional and elevates cAMP levels in insulin-secreting INS-1 cells. In addition, it stimulates insulin secretion in a glucose concentration-dependent manner. Intramuscular gene transfer of the plasmid in db/db mice demonstrated that expression of the GLP-1/Fc peptide normalizes glucose tolerance by enhancing insulin secretion and suppressing glucagon release. This strategy of using a bivalent GLP-1/Fc fusion protein as a therapeutic agent is a novel approach for the treatment of diabetes.
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Affiliation(s)
- M Kumar
- Department of Medicine, University of Toronto, Ontario, Canada
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24
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Hepner F, Csaszar E, Roitinger E, Pollak A, Lubec G. Massspectrometrical analysis of recombinant human growth hormone Norditropin® reveals amino acid exchange at M14_V14 rhGH. Proteomics 2006; 6:775-84. [PMID: 16372270 DOI: 10.1002/pmic.200500334] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recombinant human growth hormone (rhGH) is used for the treatment of several disorders. Structural integrity of rhGH is of critical importance for its clinical use and modifications thereof may act as markers in situations such as rhGH doping, as illegal rhGH-abuse in sports is of increasing interest. In the current study we investigated homogeneity of Norditropin, a recombinant human growth hormone frequently used in medicine, expressed in E. coli, strain MC1061. The most recent proteomics technologies including 2-DE, MALDI-MS followed by MALDI-MS/MS and LC-MS followed by LC-MS/MS were used for the characterisation of rhGH. MALDI-TOF-TOF and electrospray LC-MS analysis revealed one major protein with an average molecular mass of 22 126.0 Da and some additional minor components. Electrospray LC-MS/MS of the enzymatically digested Norditropin sample showed deamidation of N(12)N(149) and N(159), oxidation of M(14), M(125) and M(170) and one amino acid exchange V(14) for M(14) present in <1% of Norditropin. While deamidation and oxidation may be due to technical reasons, the single amino acid exchange may reflect infidelity of translation rather than codon usage and copy editing by E. coli.
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Affiliation(s)
- Felix Hepner
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
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25
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Zhou C, Zhang Y, Qin P, Liu X, Zhao L, Yang S, Cai Y, Qian X. A method for rapidly confirming protein N-terminal sequences by matrix-assisted laser desorption/ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:2878-84. [PMID: 16941722 DOI: 10.1002/rcm.2674] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The N-terminal sequence is important for the identification of a protein and the confirmation of its N-terminal processing. Although mass spectrometry (MS) is a sensitive and high-throughput method to sequence and identify peptides and proteins, N-terminal peptides, diluted among most of the peptides that do not originate at the N-termini, are not easy to identify directly with MS. To develop a simple and rapid method to identify and sequence the N-terminal peptide of a protein, a new strategy based on specific sulfonation of terminal amino groups and selective monitoring of the sulfonated peptide was introduced. After a protein had been guanidinated, 2-sulfobenzoylated, and reduced, it was digested with trypsin and analyzed by MS. Because of the strong acidity of sulfonic groups and the specific sulfonation of alpha-amino groups, the sulfonated N-terminal peptide dominated as base peak in the negative mode peptide mass fingerprint (PMF) and was easy to identify. The N-terminal peptide was then selected as precursor ion for tandem mass spectrometric (MS/MS) analysis. Four proteins were tested with this method and their N-terminal peptides were successfully recognized and sequenced. The results suggest that the addition of a sulfonic acid group facilitates the identification and de novo sequencing of N-terminal peptides.
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Affiliation(s)
- Chunxi Zhou
- Department of Genomics and Proteomics, Beijing Institute of Radiation Medicine, 27 Tai-Ping Road, Beijing 100850, China
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26
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Hepner F, Cszasar E, Roitinger E, Lubec G. Mass spectrometrical analysis of recombinant human growth hormone (Genotropin(R)) reveals amino acid substitutions in 2% of the expressed protein. Proteome Sci 2005; 3:1. [PMID: 15707495 PMCID: PMC549540 DOI: 10.1186/1477-5956-3-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2004] [Accepted: 02/11/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND: The structural integrity of recombinant proteins is of critical importance to their application as clinical treatments. Recombinant growth hormone preparations have been examined by several methodologies. In this study recombinant human growth hormone (rhGH; Genotropin(R)), expressed in E. coli K12, was structurally analyzed by two-dimensional gel electrophoresis and MALDI-TOF-TOF, LC-MS and LC-MS/ MS sequencing of the resolved peptides. RESULTS: Electrospray LC-MS analysis revealed one major protein with an average molecular mass of 22126.8 Da and some additional minor components. Electrospray LC-MS/MS evaluation of the enzymatically digested Genotropin(R) sample resulted in the identification of amino acid substitutions at the residues M14, M125, and M170; di-methylation of K70 (or exchange to arginine); deamidation of N149, and N152, and oxidation of M140, M125 and M170. Peak area comparison of the modified and parental peptides indicates that these changes were present in ~2% of the recombinant preparation. CONCLUSION: Modifications of the recombinant human growth hormone may lead to structural or conformational changes, modification of antigenicity and development of antibody formation in treated subjects. Amino acid exchanges may be caused by differences between human and E. coli codon usage and/or unknown copy editing mechanisms. While deamidation and oxidation can be assigned to processing events, the mechanism for possible di-methylation of K70 remains unclear.
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Affiliation(s)
- Felix Hepner
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - Edina Cszasar
- Mass Spectrometry Unit, University of Vienna, Austria
| | | | - Gert Lubec
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
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27
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Tiboni GM, Bucciarelli T, Giampietro F, Sulpizio M, Di Ilio C. Influence of cigarette smoking on vitamin E, vitamin A, beta-carotene and lycopene concentrations in human pre-ovulatory follicular fluid. Int J Immunopathol Pharmacol 2005; 17:389-93. [PMID: 15461873 DOI: 10.1177/039463200401700319] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Increasing evidence suggests that fat soluble vitamins and micronutrients have the potential for local modulation of follicular development. Cigarette smoking has been associated with accelerated follicular depletion and derangement of reproductive functions. The present study was initiated to investigate the impact of cigarette smoking on follicular and plasma concentrations of vitamin A, vitamin E, lycopene and beta-carotene. Samples were collected from 17 smokers and 43 non-smoking women undergoing assisted reproduction techniques. Assays were carried out by a reverse-phase high-pressure liquid chromatography (HPLC) method. Smokers had significantly (P < 0.05) lower levels of follicular fluid beta-carotene in comparison to non-smokers (0.02 +/- 0.02 vs. 0.09 +/- 0.02, respectively). No other significant influences on follicular and plasma concentrations were noted. Smokers showed a significantly (P < 0.05) lower fertilization rate in comparison to non-smokers, (55.9 % vs. 71.5 % , respectively). It is postulated that follicular depletion of the antioxidant beta-carotene occurs in response to oxidative stress imposed by cigarette smoke.
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Affiliation(s)
- G M Tiboni
- Sezione di Ostetricia e Ginecologia, Dipartimento di Medicina e Scienze dell'Invecchiamento, Universitá "G. D'Annunzio", Chieti, Italy.
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