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Favreau M, Menu E, Gaublomme D, Vanderkerken K, Faict S, Maes K, De Bruyne E, Govindarajan S, Drennan M, Van Calenbergh S, Leleu X, Zabeau L, Tavernier J, Venken K, Elewaut D. Leptin receptor antagonism of iNKT cell function: a novel strategy to combat multiple myeloma. Leukemia 2017; 31:2678-2685. [PMID: 28490813 DOI: 10.1038/leu.2017.146] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 04/27/2017] [Accepted: 05/03/2017] [Indexed: 12/28/2022]
Abstract
A hallmark of bone marrow changes with aging is the increase in adipocyte composition, but how this impacts development of multiple myeloma (MM) is unknown. Here, we report the role of the adipokine leptin as master regulator of anti-myeloma tumor immunity by modulating the invariant natural killer T (iNKT) cell function. A marked increase in serum leptin levels and leptin receptor (LR) expression on iNKT cells in MM patients and the 5T33 murine MM model was observed. MM cells and leptin synergistically counteracted anti-tumor functionality of both murine and human iNKT cells. In vivo blockade of LR signaling combined with iNKT stimulation resulted in superior anti-tumor protection. This was linked to persistent IFN-γ secretion upon repeated iNKT cell stimulation and a restoration of the dynamic antigen-induced motility arrest as observed by intravital microscopy, thereby showing alleviation of iNKT cell anergy. Overall our data reveal the LR axis as novel therapeutic target for checkpoint inhibition to treat MM.
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Affiliation(s)
- M Favreau
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - E Menu
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - D Gaublomme
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - K Vanderkerken
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - S Faict
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - K Maes
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - E De Bruyne
- Department of Hematology and Immunology, Myeloma Center Brussels, Vrije Universiteit Brussel, Brussels, Belgium
| | - S Govindarajan
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - M Drennan
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - S Van Calenbergh
- Laboratory for Medicinal Chemistry, Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - X Leleu
- Service d'Hématologie et Thérapie Cellulaire, Pôle Régional de Cancérologie, Hospital de la Miléterie, Poitiers, France
| | - L Zabeau
- Department of Biochemistry, VIB Medical Biotechnology Center, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - J Tavernier
- Department of Biochemistry, VIB Medical Biotechnology Center, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - K Venken
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
| | - D Elewaut
- Department of Rheumatology, Ghent University Hospital, Ghent, Belgium.,Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent, Belgium
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Venken K, Melis L, Jacques P, Van Praet L, De Bock W, Piette Y, van den Bosch F, Verbruggen G, Elewaut D. AB0190 Synovial fluid derived invariant natural killer T cells in chronic arthritides show an increased programmed death-1 expression and anergic phenotype. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2012-eular.190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Szabad J, Venken K, Bellen H, Soós I. P-1 Detection and quantitative evaluation of chromosome loss induced in Drosophila wing primordial cells. Reprod Biomed Online 2013. [DOI: 10.1016/s1472-6483(13)60064-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Aspeslagh S, Li Y, Yu ED, Pauwels N, Trappeniers M, Girardi E, Decruy T, Van Beneden K, Venken K, Drennan M, Leybaert L, Wang J, Van Calenbergh S, Zajonc DM, Elewaut D. Galactose modified iNKT cell agonists stabilised by a novel structural modification of CD1d lead to marked Th1 polarisation in vivo. Ann Rheum Dis 2011. [DOI: 10.1136/ard.2010.148981.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Vanderschueren D, Pye SR, Venken K, Borghs H, Gaytant J, Huhtaniemi IT, Adams JE, Ward KA, Bartfai G, Casanueva FF, Finn JD, Forti G, Giwercman A, Han TS, Kula K, Labrie F, Lean MEJ, Pendleton N, Punab M, Silman AJ, Wu FCW, O'Neill TW, Boonen S. Gonadal sex steroid status and bone health in middle-aged and elderly European men. Osteoporos Int 2010; 21:1331-9. [PMID: 20012940 DOI: 10.1007/s00198-009-1144-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Accepted: 09/03/2009] [Indexed: 10/20/2022]
Abstract
SUMMARY The influence of sex steroids on calcaneal quantitative ultrasound (QUS) parameters was assessed in a population sample of middle-aged and elderly European men. Higher free and total E(2) though not testosterone, were independently associated with higher QUS parameters. INTRODUCTION The aim of this study was to investigate the association between QUS parameters and sex steroids in middle-aged and elderly European men. METHODS Three thousand one hundred forty-one men aged between 40 and 79 years were recruited from eight European centres for participation in a study of male ageing: the European Male Ageing Study. Subjects were invited by letter to attend for an interviewer-administered questionnaire, blood sample and QUS of the calcaneus (Hologic-SAHARA). Blood was assessed for sex steroids including oestradiol (E(2)), testosterone (T), free and bio-available E(2) and T and sex hormone binding globulin (SHBG). RESULTS Serum total T was not associated with any of the QUS parameters. Free T and both free and total E(2) were positively related to all QUS readings, while SHBG concentrations were negatively associated. These relationships were observed in both older and younger (<60 years) men. In a multivariate model, after adjustment for age, centre, height, weight, physical activity levels and smoking, free E(2) and SHBG, though not free T, remained independently associated with the QUS parameters. After further adjustment for IGF-1, however, the association with SHBG became non-significant. CONCLUSION Higher free and total E(2) are associated with bone health not only among the elderly but also middle-aged European men.
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Affiliation(s)
- D Vanderschueren
- Department of Andrology and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium.
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Ophoff J, Venken K, Callewaert F, Boonen S, Bouillon R, Vanderschueren D. Sex steroids during bone growth: a comparative study between mouse models for hypogonadal and senile osteoporosis. Osteoporos Int 2009; 20:1749-57. [PMID: 19238307 DOI: 10.1007/s00198-009-0851-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Accepted: 01/23/2009] [Indexed: 11/28/2022]
Abstract
SUMMARY In this study, the role of disturbed bone mineral acquisition during puberty in the pathogenesis of osteoporosis was studied. To this end, a mouse model for senile and hypogonadal osteoporosis was used. Longitudinal follow-up showed that bone fragility in both models results from deficient bone build-up during early puberty. INTRODUCTION Male osteoporosis may result from impaired bone growth. This study characterizes the mechanisms of deficient peak bone mass acquisition in models for senile (SAMP6) and hypogonadal (orchidectomized SAMR1) osteoporosis. METHODS Bone mineral acquisition was investigated longitudinally in SAMP6 and orchidectomized SAMR1 mice (eight to ten animals per group) using peripheral quantitative computed tomography and histomorphometry. Additionally, the effects of long-term 5alpha-dihydrotestosterone (DHT) and 17beta-estradiol (E2) replacement were studied. Statistical analysis was performed using ANOVA and Student's t test. RESULTS SAMP6 mice showed an early (4 weeks) medullary expansion of the cortex due to impaired endocortical bone formation (-43%). Despite compensatory periosteal bone formation (+47%), cortical thickness was severely reduced in 20-week-old SAMP6 versus SAMR1. Orchidectomy reduced periosteal apposition between 4 and 8 weeks of age and resulted in high bone turnover and less trabecular bone gain in SAMP6 and SAMR1. DHT and E2 stimulated periosteal expansion and trabecular bone in orchidectomized SAMP6 and SAMR1. E2 stimulated endocortical apposition in SAMP6. Moreover, sex steroid action occurred between 4 and 8 weeks of age. CONCLUSION Bone fragility in both models resulted from deficient bone build-up during early puberty. DHT and E2 improved bone mass acquisition in orchidectomized animals, suggesting a role for AR and ER in male skeletal development.
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Affiliation(s)
- J Ophoff
- Bone Research Unit, Laboratory for Experimental Medicine and Endocrinology, Department of Experimental Medicine, Katholieke Universiteit Leuven, Herestraat 49, 3000, Leuven, Belgium.
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Abstract
Sex steroids regulate skeletal maturation and preservation in both men and women, as already recognized in the 1940s by Albright and Reifenstein. The impact of gonadal insufficiency on skeletal integrity has been widely recognized in adult men and women ever since. In the context of their skeletal actions, androgens and estrogens are no longer considered as just male and female hormones, respectively. Androgens can be converted into estrogens within the gonads and peripheral tissues and both are present in men and women, albeit in different concentrations. In the late 1980s, sex steroid receptors were discovered in bone cells. However, the understanding of sex steroid receptor activation and translation into biological skeletal actions is still incomplete. Due to the complex metabolism, sex steroids may have not only endocrine but also paracrine and/or autocrine actions. Also, circulating sex steroid concentrations do not necessarily reflect their biological activity due to strong binding to sex hormone binding globulin (SHBG). Finally, sex steroid signaling may include genomic and non-genomic effects in bone and non-bone cells. This review will focus on our current understanding of gonadal steroid metabolism, receptor activation, and their most relevant cellular and biological actions on bone.
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Affiliation(s)
- K Venken
- Bone Research Unit, Laboratory for Experimental Medicine and Endocrinology, Department of Experimental Medicine, Katholieke Universiteit Leuven, Herestraat 49, Box 902, B-3000, Leuven, Belgium
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Boonen S, Vanderschueren D, Venken K, Milisen K, Delforge M, Haentjens P. Recent developments in the management of postmenopausal osteoporosis with bisphosphonates: enhanced efficacy by enhanced compliance. J Intern Med 2008; 264:315-32. [PMID: 18823505 DOI: 10.1111/j.1365-2796.2008.02010.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bisphosphonates are the current mainstay of treatment for postmenopausal osteoporosis. Although daily oral dosing is effective, it is associated with poor compliance, partly because of the pre and postdose fasting and posture requirements. This negatively impacts treatment outcomes, leading to a reduced clinical benefit. Improved, yet still suboptimal adherence has been noticed with less frequent bisphosphonate dosing e.g. once-weekly and once-monthly oral regimens. The recently approved quarterly intravenous (i.v.) injection regimen of ibandronate and yearly i.v. infusion of zoledronic acid are attractive options in the management of postmenopausal osteoporosis. These regimens may assure quarterly and year long compliance.
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Affiliation(s)
- S Boonen
- Leuven University, Department of Experimental Medicine, Leuven, Belgium.
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Haentjens P, Autier P, Barette M, Venken K, Vanderschueren D, Boonen S. Survival and functional outcome according to hip fracture type: a one-year prospective cohort study in elderly women with an intertrochanteric or femoral neck fracture. Bone 2007; 41:958-64. [PMID: 17913614 DOI: 10.1016/j.bone.2007.08.026] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 07/10/2007] [Accepted: 08/21/2007] [Indexed: 11/22/2022]
Abstract
We conducted a prospective study among elderly women with a first hip fracture to document survival and functional outcome and to determine whether outcomes differ by fracture type. The design was a one-year prospective cohort study in the context of standard day-to-day clinical practice. The main outcome measures were survival and functional outcome, both at hospital discharge and 1 year later. Functional outcome was assessed using the Rapid Disability Rating Scale version-2. Of the 170 women originally enrolled, 86 (51%) had an intertrochanteric and 84 (49%) a femoral neck fracture. There were no significant differences between the two groups with respect to median age (80 and 78 years, respectively), type and number of comorbidities and prefracture residence at the time of injury. At hospital discharge, intertrochanteric hip fracture patients had a higher mortality (p=0.006) and were functionally more impaired (p=0.005). One year later, mortality was still significantly higher after intertrochanteric fracture (relative risk 2.5; 95% confidence interval: 1.3 to 5.1; p=0.008), but functional outcome among surviving patients was similar in both groups. We conclude that intertrochanteric fractures are associated with increased mortality compared to femoral neck fractures. Functional outcome differs according to fracture type at hospital discharge, but these differences do not persist over time. These differences cannot be explained by differences in age or comorbidity. To address the mechanism(s) by which intertrochanteric fractures carry excess mortality compared to femoral neck fractures, future studies in hip fracture patients should include a comprehensive assessment of the degree of frailty, vitamin D status, and fall dynamics.
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Affiliation(s)
- P Haentjens
- Department of Orthopaedics and Traumatology, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Laarbeeklaan 101, B-1090 Brussels, Belgium.
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Lindberg MK, Svensson J, Venken K, Chavoshi T, Andersson N, Movérare Skrtic S, Isaksson O, Vanderschueren D, Carlsten H, Ohlsson C. Liver-derived IGF-I is permissive for ovariectomy-induced trabecular bone loss. Bone 2006; 38:85-92. [PMID: 16257281 DOI: 10.1016/j.bone.2005.07.027] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Revised: 05/26/2005] [Accepted: 07/08/2005] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Estrogen deficiency results in trabecular bone loss, associated with T-cell proliferation in the bone marrow. Insulin-like growth factor I (IGF-I) is involved in the regulation of both bone metabolism and lymphopoiesis. A major part of serum IGF-I is derived from the liver. The aim of the present study was to investigate the role of liver-derived IGF-I for ovariectomy (ovx)-induced trabecular bone loss. MATERIALS AND METHODS Mice with adult liver-specific IGF-I inactivation (LI-IGF-I-/-) and wild type mice (WT) were either ovx or sham operated. After 5 weeks, the skeletal phenotype was analyzed by pQCT and microCT. The bone marrow cellularity was analyzed using FACS technique, and mRNA levels were quantified using real-time PCR. RESULTS Ovx resulted in a pronounced reduction in trabecular bone mineral density (-52%, P < 0.001), number (-45%, P < 0.01) and thickness (-13%, P < 0.01) in WT mice while these bone parameters were unaffected by ovx in LI-IGF-I-/- mice. Furthermore, ovx increased the number of T-cells in the bone marrow of the femur in WT but not in LI-IGF-I-/- mice. Interleukin 7 (IL-7) has been reported to stimulate the formation and function of osteoclasts by inducing the expression of receptor activator of NF-kappaB ligand (RANKL) on T-cells. IL-7 mRNA levels and the RANKL/osteoprotegerin ratio in bone were increased by ovx in WT but not in LI-IGF-I-/- mice. CONCLUSIONS Liver-derived IGF-I is permissive for ovx-induced trabecular bone loss. Our studies indicate that IGF-I might exert this permissive action by modulation of the number of T-cells and the expression of IL-7, which in turn is of importance for the RANKL/OPG ratio and consequently osteoclastogenesis in the bone marrow.
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Affiliation(s)
- M K Lindberg
- Center for Bone Research, Department of Internal Medicine, Div. of Endocrinology, Sahlgrenska Academy, Göteborg University, Bruna Stråket 16, 41345 Gothenburg, Sweden.
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Boonen S, Vanderschueren D, Venken K, Geusens P, Haentjens P, Mohan S, Baylink D, Bouillon R. Differences in exposure to stimulatory and inhibitory components of the insulin-like growth factor (IGF) system in patients with femoral neck versus trochanteric fracture. Age Ageing 2005; 34:175-8. [PMID: 15713863 PMCID: PMC2903003 DOI: 10.1093/ageing/afi013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- S. Boonen
- Leuven University Center for Metabolic Bone Diseases, Katholieke Universiteit Leuven, Leuven, Belgium
- Leuven University Division of Geriatric Medicine, Katholieke Universiteit Leuven, Leuven, Belgium
- Leuven University Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
- To whom correspondence should be addressed at: Leuven University Center for Metabolic Bone Diseases and Division of Geriatric Medicine, Universitaire Ziekenhuizen K.U.Leuven, Herestraat 49, B-3000 Leuven, Belgium Fax: (+32) 16 34 26 41
| | - D. Vanderschueren
- Leuven University Center for Metabolic Bone Diseases, Katholieke Universiteit Leuven, Leuven, Belgium
- Leuven University Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - K. Venken
- Leuven University Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - P. Geusens
- Limburg University Center, Diepenbeek, Belgium
- Maastricht University Hospital, Maastricht, The Netherlands
| | - P. Haentjens
- Brussels University Department of Traumatology and Emergency Surgery, Vrije Universiteit Brussel, Brussels, Belgium
| | - S. Mohan
- Musculoskeletal Disease Center, Jerry L Pettis VA Medical Center, Loma Linda, CA, USA
- Loma Linda University Departments of Medicine and Biochemistry, Loma Linda, CA, USA
| | - D.J. Baylink
- Musculoskeletal Disease Center, Jerry L Pettis VA Medical Center, Loma Linda, CA, USA
- Loma Linda University Departments of Medicine and Biochemistry, Loma Linda, CA, USA
| | - R. Bouillon
- Leuven University Center for Metabolic Bone Diseases, Katholieke Universiteit Leuven, Leuven, Belgium
- Leuven University Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
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Reyns GE, Venken K, Morreale de Escobar G, Kühn ER, Darras VM. Dynamics and regulation of intracellular thyroid hormone concentrations in embryonic chicken liver, kidney, brain, and blood. Gen Comp Endocrinol 2003; 134:80-7. [PMID: 13129506 DOI: 10.1016/s0016-6480(03)00220-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The intracellular thyroid hormone (TH) availability is influenced by different metabolic pathways. We investigated the relationship between tissue and plasma TH levels as well as the correlation with changes of deiodination and sulfation during chicken embryonic development. From day 14 until day 19, T3 remains unchanged in liver and kidney in spite of increasing plasma T4 and T3 levels and a slightly increased T4 availability in these tissues. During this period, the T3 breakdown capacity by type III deiodinase (D3) is high in liver but low in kidney. The TH inactivation capacity of type I deiodinase (D1), with production of inactive rT3 instead of T3, in kidney seems to be potentiated by the sulfation pathway. A sharp rise in T3 and T4 is detected in all tissues examined when the embryo switches to lung respiration. The same day, T4 content in liver is sharply enhanced and sulfation activity is decreased. So, T4 availability in liver is increased while a declined D3 activity allows for the accumulation of hepatic T3. The increase in renal T3 and T4 are more closely related to plasma TH profiles and a lack of correlation with the changes in renal D1 and D3 activity suggests that T4 and T3 content in this organ is strongly dependent on direct uptake from the blood. Despite much lower T4 levels, T3 levels in brain are in the same range as in liver and kidney and intracellular T3 even exceeds the T4 levels towards the end of development. The rise in TH content coincides with a drop in D3 activity, low sulfation activity and an increased T3 production capacity via type II deiodinase (D2). In conclusion, the current study describes the dynamics of intracellular TH concentrations in liver, kidney, and brain during chicken development and investigates their relationship with circulating TH levels and changes of deiodinases and sulfotransferases. The clear differences in intracellular TH profiles among the different tissues demonstrate that circulating levels are not necessarily representative for the local TH changes. Some of the changes in intracellular TH availability can be linked to changes in local deiodination and sulfation capacities, but the importance of these enzyme systems in relation to other factors, such as hormone uptake, differs between liver, kidney, and brain.
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Affiliation(s)
- G E Reyns
- Laboratory of Comparative Endocrinology, Zoological Instistute, K.U. Leuven, Naamsestraat 61, Leuven B-3000, Belgium.
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Irobi J, Nelis E, Meuleman J, Venken K, De Jonghe P, Van Broeckhoven C, Timmerman V. Exclusion of 5 functional candidate genes for distal hereditary motor neuropathy type II (distal HMN II) linked to 12q24.3. Ann Hum Genet 2001; 65:517-29. [PMID: 11851982 DOI: 10.1017/s0003480001008910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Distal hereditary motor neuropathies (distal HMNs) are characterised by degeneration of anterior horn cells of the spinal cord resulting in muscle weakness and atrophy. Distal HMN type II is genetically linked to chromosome 12q24.3 and located within a 13 cM region flanked by markers D12S86 and D12S340. We previously excluded the human phospholipase A2 group 1B gene (PLA2G1B) as the disease causing gene. Here, we report the mutation analysis of five other candidate genes localised within the distal HMN II region: the cytoskeletal proteins paxillin (PXN) and restin (RSN); the acidic ribosomal phosphoprotein, large P0 subunit (RPLP0); a nucleoside diphosphate kinase (NME2B); and the beta 3 subunit of the voltage-gated calcium channel (CACNB3). DNA sequencing of the coding regions was performed but no disease causing mutations could be identified, hence excluding these five genes for distal HMN type II.
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Affiliation(s)
- J Irobi
- Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, Born-Bunge Foundation, University of Antwerp, Belgium
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Venken K, Meuleman J, Irobi J, Ceuterick C, Martini R, De Jonghe P, Timmerman V. Caspr1/Paranodin/Neurexin IV is most likely not a common disease-causing gene for inherited peripheral neuropathies. Neuroreport 2001; 12:2609-14. [PMID: 11496158 DOI: 10.1097/00001756-200108080-00063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Contactin associated protein 1 (Caspr1/Paranodin/Neurexin IV) is an axonal transmembrane molecule mainly localised at the paranodal junction. Since molecular alterations in septate-like junctions at the paranodes might have important consequences for the function of the nerve fiber, we considered that Caspr1 could be involved in the pathogenesis of inherited peripheral neuropathies. In this study, we physically mapped the Caspr1 gene on chromosome 17q21.1 and determined its genomic structure. We performed a mutation analysis of the Caspr1 gene in a cohort of 64 unrelated patients afflicted with distinct inherited peripheral neuropathies. Since no disease causing mutations were found, we suggest that Caspr1 is probably not a common cause of inherited peripheral neuropathies.
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Affiliation(s)
- K Venken
- Peripheral Neuropathy Group, Molecular Genetics Department, Flanders Interuniversity Institute for Biotechnology (VIB), B-2610 Antwerpen, Belgium
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