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Mousikou M, Kyriakou A, Skordis N. Stress and Growth in Children and Adolescents. Horm Res Paediatr 2023; 96:25-33. [PMID: 34814153 DOI: 10.1159/000521074] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/19/2021] [Indexed: 11/19/2022] Open
Abstract
The infantile, childhood, and adolescent periods of growth and development also represent times of increased vulnerability to stressors. Growth velocity in each period is dependent on the interplay of genetic, environmental, dietary, socioeconomic, developmental, behavioral, nutritional, metabolic, biochemical, and hormonal factors. A stressor may impact growth directly through modulation of the growth hormone axis or indirectly through other factors. The adaptive response to stressors culminates in behavioral, physiological, and biochemical responses which together support survival and conservation of energy. The immediate response involves activation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis. The time-limited stress response is at once antigrowth, antireproductive, and catabolic with no lasting adverse consequences. However, chronic activation of the stress system and hypercortisolism have consequential negative impacts on growth, thyroid function, reproduction-puberty, and metabolism. High cortisol suppresses growth hormone-insulin-like growth factor 1, hypothalamic-pituitary-gonadal, and thyroid axes and has been reported to be responsible for an increase in visceral adiposity, a decrease in lean mass, suppression of osteoblastic activity with risk of osteoporosis, and induction of insulin resistance. Early-life adversities, emotional or physical, have been associated with long-term negative physical and mental health outcomes. Existing models of chronic stress corroborate that early-life adversities can affect growth and have consequences in other aspects of well-being throughout the lifespan. Targeted interventions to reduce stress during infancy, childhood, and adolescence can have far-reaching benefits to long-term health as well as attaining adequate growth. In this review, we describe the neuroendocrinology of the stress response, the factors influencing growth, and the impact of chronic stress on growth during critical periods of infancy, childhood, and puberty with particular reference to growth, thyroid, and gonadal axis.
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Affiliation(s)
- Maria Mousikou
- Department of Paediatric Endocrinology, Makarios Children's Hospital, Nicosia, Cyprus
| | - Andreas Kyriakou
- Department of Paediatric Endocrinology, Makarios Children's Hospital, Nicosia, Cyprus
| | - Nicos Skordis
- Division of Pediatric Endocrinology, Paedi Center for Specialized Pediatrics, Nicosia, Cyprus.,School of Medicine, University of Nicosia, Nicosia, Cyprus
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Shalitin S, Gat-Yablonski G. Associations of Obesity with Linear Growth and Puberty. Horm Res Paediatr 2022; 95:120-136. [PMID: 34130293 DOI: 10.1159/000516171] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 03/27/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The prevalence of obesity in childhood has increased dramatically in recent decades with increased risk of developing cardiometabolic and other comorbidities. Childhood adiposity may also influence processes of growth and puberty. SUMMARY Growth patterns of obesity during childhood have been shown to be associated with increased linear growth in early childhood, leading to accelerated epiphyseal growth plate (EGP) maturation. Several hormones secreted by the adipose tissue may affect linear growth in the context of obesity, both via the growth hormone IGF-1 axis and via a direct effect on the EGP. The observation that children with obesity tend to mature earlier than lean children has led to the assumption that the degree of body fatness may trigger the neuroendocrine events that lead to pubertal onset. The most probable link between obesity and puberty is leptin and its interaction with the kisspeptin system, which is an important regulator of puberty. However, peripheral action of adipose tissue could also be involved in changes in the onset of puberty. In addition, nutritional factors, epigenetics, and endocrine-disrupting chemicals are potential mediators linking pubertal onset to obesity. In this review, we focused on interactions of obesity with linear growth and pubertal processes, based on basic research and clinical data in humans. KEY MESSAGE Children with obesity are subject to accelerated linear growth with risk of impaired adult height and early puberty, with its psychological consequences. The data highlight another important objective in combatting childhood obesity, for the prevention of abnormal growth and pubertal patterns.
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Affiliation(s)
- Shlomit Shalitin
- National Center for Childhood Diabetes, Schneider Children's Medical Center of Israel, The Jesse Z and Sara Lea Shafer Institute for Endocrinology and Diabetes, Petach Tikva, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Galia Gat-Yablonski
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Felsenstein Medical Research Center, Petach Tikva, Israel
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Jin LY, Guo C, Xu S, Liu HY, Li XF. The Role of Estrogen Receptor α in Response to Longitudinal Bone Growth in ob/ob Mice. Front Endocrinol (Lausanne) 2021; 12:749449. [PMID: 34925230 PMCID: PMC8671758 DOI: 10.3389/fendo.2021.749449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/06/2021] [Indexed: 12/18/2022] Open
Abstract
The absence of leptin results in contrasting growth pattern of appendicular and axial bone growth in ob/ob mice. Endochondral bone formation is an important procedure of growth plate determining the bone growth, where this procedure is also regulated by estrogen and its receptor (ER) signaling pathway. The present study is undertaken to explore the roles of ERs in regulating the different growth patterns in ob/ob mice. In this study, C57BL/6 female mice were used as wild-type (WT) mice; ob/ob mice and WT mice were age-matched fed, and bone length is analyzed by X-ray plain film at the 12 weeks old. We confirm that ob/ob mice have shorter femoral length and longer spine length than WT mice (p < 0.05). The contrasting expression patterns of chondrocyte proliferation proteins and hypertrophic marker proteins are also observed from the femur and spinal growth plate of ob/ob mice compared with WT mice (p < 0.01). Spearman's analysis showed that body length (axial and appendicular length) is positively related to the expression level of ERα in growth plate. Three-week-old female ob/ob mice are randomized divided into three groups: 1) ob/ob + ctrl, 2) ob/ob + ERα antagonist (MPP), and 3) ob/ob + ERβ antagonist (PHTPP). Age-matched C57BL/6 mice were also divided into three groups, same as the groups of ob/ob mice. MPP and PHTPP were administered by intraperitoneal injection for 6 weeks. However, the results of X-ray and H&E staining demonstrate that leptin deficiency seems to disturb the regulating effects of ER antagonists on longitudinal bone growth. These findings suggested that region-specific expression of ERα might be associated with contrasting phenotypes of axial and appendicular bone growth in ob/ob mice. However, ER signaling on longitudinal bone growth was blunted by leptin deficiency in ob/ob mice, and the underlying association between ERs and leptin needs to be explored in future work.
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Affiliation(s)
- Lin-Yu Jin
- Department of Spinal Surgery, Peking University People's Hospital, Peking University, Beijing, China
| | - Chen Guo
- Department of Spinal Surgery, Peking University People's Hospital, Peking University, Beijing, China
| | - Shuai Xu
- Department of Spinal Surgery, Peking University People's Hospital, Peking University, Beijing, China
| | - Hai-Ying Liu
- Department of Spinal Surgery, Peking University People's Hospital, Peking University, Beijing, China
| | - Xin-Feng Li
- Department of Spinal Surgery, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
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Jiang LF, Fang JH, Wu LD. Role of infrapatellar fat pad in pathological process of knee osteoarthritis: Future applications in treatment. World J Clin Cases 2019; 7:2134-2142. [PMID: 31531309 PMCID: PMC6718789 DOI: 10.12998/wjcc.v7.i16.2134] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 06/11/2019] [Accepted: 06/27/2019] [Indexed: 02/05/2023] Open
Abstract
It has been found that obese people have a higher proportion in suffering from osteoarthritis (OA), not only in the weight-bearing joints like knee and hip joints, even in non-weight-bearing joints such as hand joints. One of the reasons is because the large amount of adipose tissue secretes some factors, which can promote the occurrence of arthritis. As an important structure of the knee joint, the infrapatellar fat pad (IPFP) is actually a piece of adipose tissue. The aim of this review is to offer a comprehensive view of the anatomy and physiological characteristics of IPFP and its relationship with the pathological process of OA, indicating the important function of IPFP in OA. At the same time, with the development of adipose derived stem cells in the treatment of OA, owing to its special advantages, the IPFP is becoming a kind of important, minimally invasive fat stem cell source, providing a new approach for the treatment of OA. We hope that this review will offer an overview of all published data regarding the IPFP and will indicate novel directions for future research.
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Affiliation(s)
- Li-Feng Jiang
- Department of Orthopedics Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
| | - Jing-Hua Fang
- Department of Orthopedics Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
| | - Li-Dong Wu
- Department of Orthopedics Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
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Fu R, Han F, Liu L, Yu F, Gui Z, Wang X, Li B, Fang B, Xia L. The Effects of Leptin on the Proliferation and Differentiation of Primary Chondrocytes in Vitro and Cartilage Regeneration in Vivo. ACS Biomater Sci Eng 2019; 5:1907-1919. [PMID: 33405564 DOI: 10.1021/acsbiomaterials.8b01168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Runqing Fu
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Fengxuan Han
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Lu Liu
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Fei Yu
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Zhipeng Gui
- Department of Oral Surgery, Shanghai Ninth People’s Hospital Affiliated with Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Xiaoting Wang
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Bin Li
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Bing Fang
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Lunguo Xia
- Department of Orthodontics, Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China
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Masarwi M, Shamir R, Phillip M, Gat-Yablonski G. Leptin stimulates aromatase in the growth plate: limiting catch-up growth efficiency. J Endocrinol 2018; 237:229-242. [PMID: 29615477 DOI: 10.1530/joe-18-0028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 04/03/2018] [Indexed: 12/15/2022]
Abstract
Catch-up growth (CUG) in childhood is defined as periods of growth acceleration, after the resolution of growth attenuation causes, bringing the children back to their original growth trajectory. Sometimes, however, CUG is incomplete, leading to permanent growth deficit and short stature. The aim of this study was to investigate the mechanisms that limit nutritional-CUG. Specifically, we focused on the crosstalk between leptin, increased by re-feeding, and sex hormones, which increase with age. In vivo studies were performed in young male Sprague Dawley rats fed ad libitum or subjected to 10/36 days of 40% food restriction followed by 90-120 days of re-feeding. In vitro studies were performed on ATDC5 cells. Analyses of mRNA and protein levels were done using qPCR and Western blot, respectively. CUG was complete in body weight and humerus length in animals that were food-restricted for 10 days but not for those food-restricted for 36 days. In vitro studies showed that leptin significantly increased aromatase gene expression and protein level as well as the expression of estrogen and leptin receptors in a dose- and time-dependent manner. The effect of leptin on aromatase was direct and was mediated through the MAPK/Erk, STAT3 and PI3K pathways. The crosstalk between leptin and aromatase in the growth plate suggests that re-feeding during puberty may lead to increased estrogen level and activity, and consequently, irreversible premature epiphyseal growth plate closure. These results may have important implications for the development of novel treatment strategies for short stature in children.
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Affiliation(s)
- Majdi Masarwi
- Sackler Faculty of MedicineTel Aviv University, Tel Aviv, Israel
- Felsenstein Medical Research CenterPetach Tikva, Israel
| | - Raanan Shamir
- Sackler Faculty of MedicineTel Aviv University, Tel Aviv, Israel
- Felsenstein Medical Research CenterPetach Tikva, Israel
- Institute of GastroenterologyNutrition and Liver Diseases, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Moshe Phillip
- Sackler Faculty of MedicineTel Aviv University, Tel Aviv, Israel
- Felsenstein Medical Research CenterPetach Tikva, Israel
- The Jesse Z and Sara Lea Shafer Institute for Endocrinology and DiabetesNational Center for Childhood Diabetes, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Galia Gat-Yablonski
- Sackler Faculty of MedicineTel Aviv University, Tel Aviv, Israel
- Felsenstein Medical Research CenterPetach Tikva, Israel
- The Jesse Z and Sara Lea Shafer Institute for Endocrinology and DiabetesNational Center for Childhood Diabetes, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
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Benyi E, Sävendahl L. The Physiology of Childhood Growth: Hormonal Regulation. Horm Res Paediatr 2018; 88:6-14. [PMID: 28437784 DOI: 10.1159/000471876] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/21/2017] [Indexed: 11/19/2022] Open
Abstract
The growth patterns of a child changes from uterine life until the end of puberty. Height velocity is highest in utero and declines after birth until puberty when it rises again. Important hormonal regulators of childhood growth are growth hormone, insulin-like growth factor 1, sex steroids, and thyroid hormone. This review gives an overview of these hormonal regulators of growth and their interplay with nutrition and other key players such as inflammatory cytokines.
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Gat-Yablonski G, De Luca F. Effect of Nutrition on Statural Growth
. Horm Res Paediatr 2018; 88:46-62. [PMID: 28365689 DOI: 10.1159/000456547] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/11/2017] [Indexed: 12/14/2022] Open
Abstract
In children, proper growth and development are often regarded as a surrogate marker for good health. A complex system controls the initiation, rate, and cessation of growth, and thus gives a wonderful example of the interactions between genetics, epigenetics, and environmental factors (especially stress and nutrition). Malnutrition is considered a leading cause of growth attenuation in children. This review summarizes our current knowledge regarding the mechanisms linking nutrition and skeletal growth, including systemic factors, such as insulin, growth hormone, insulin-like growth factor-1, fibroblast growth factor-21, etc., and local mechanisms, including mTOR, miRNAs, and epigenetics. Studying the molecular mechanisms regulating skeletal growth may lead to the establishment of better nutritional and therapeutic regimens for more effective linear growth in children with malnutrition and growth abnormalities.
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Affiliation(s)
- Galia Gat-Yablonski
- The Jesse Z and Sara Lea Shafer Institute for Endocrinology and Diabetes, National Center for Children's Diabetes, Schneider Children's Medical Center of Israel, Petach Tikva, Israel.,Felsenstein Medical Research Center, Petach Tikva, Israel.,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Francesco De Luca
- Section of Endocrinology and Diabetes, St. Christopher's Hospital for Children, Department of Pediatrics, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
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Therapeutic Effects of Olive and Its Derivatives on Osteoarthritis: From Bench to Bedside. Nutrients 2017; 9:nu9101060. [PMID: 28954409 PMCID: PMC5691677 DOI: 10.3390/nu9101060] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 09/11/2017] [Accepted: 09/20/2017] [Indexed: 01/11/2023] Open
Abstract
Osteoarthritis is a major cause of morbidity among the elderly worldwide. It is a disease characterized by localized inflammation of the joint and destruction of cartilage, leading to loss of function. Impaired chondrocyte repair mechanisms, due to inflammation, oxidative stress and autophagy, play important roles in the pathogenesis of osteoarthritis. Olive and its derivatives, which possess anti-inflammatory, antioxidant and autophagy-enhancing activities, are suitable candidates for therapeutic interventions for osteoarthritis. This review aimed to summarize the current evidence on the effects of olive and its derivatives, on osteoarthritis and chondrocytes. The literature on animal and human studies has demonstrated a beneficial effect of olive and its derivatives on the progression of osteoarthritis. In vitro studies have suggested that the augmentation of autophagy (though sirtuin-1) and suppression of inflammation by olive polyphenols could contribute to the chondroprotective effects of olive polyphenols. More research and well-planned clinical trials are required to justify the use of olive-based treatment in osteoarthritis.
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Yu B, Jiang K, Chen B, Wang H, Li X, Liu Z. Leptin differentially regulates chondrogenesis in mouse vertebral and tibial growth plates. BMC Musculoskelet Disord 2017; 18:235. [PMID: 28569158 PMCID: PMC5452289 DOI: 10.1186/s12891-017-1601-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 05/22/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Leptin plays an important role in mediating chondrogenesis of limb growth plate. Previous studies suggest that bone structures and development of spine and limb are different. The expression of Ob-Rb, the gene that encodes leptin receptors, is vertebral and appendicular region-specific, suggesting the regulation of leptin on VGP and TGP chondrogenesis may be very different. The aim of the present study was to investigate the differential regulation of leptin on the chondrogenesis of vertebral growth plate (VGP) and tibial growth plate (TGP). METHODS We compared the VGP and TGP from wild type (C57BL/6) and leptin-deficient (ob/ob) mice. We then generated primary cultures of TGP and VGP chondrocytes. By treating the primary cells with different concentrations of leptin in vitro, we analyzed proliferation and apoptosis of the primary chondrocytes from TGP and VGP. We further measured expression of chondrogenic-related genes in these cells that had been incubated with different doses of leptin. RESULTS Leptin-deficient mice of 8-week-old had shorter tibial and longer vertebral lengths than the wide type mice. Disturbed columnar structure was observed for TGP but not for VGP. In primary chondrocyte cultures, leptin inhibited VGP chondrocyte proliferation but promoted their apoptosis. Collagen IIA and aggrecan mRNA, and the protein levels of proliferation- and chondrogenesis-related markers, including PCNA, Sox9, and Smad4, were downregulated by leptin in a dose-dependent manner. In contrast, leptin stimulated the proliferation and chondrogenic differentiation of TGP chondrocytes at physiological levels (i.e., 10 and 50 ng/mL) but not at high levels (i.e., 100 and 1000 ng/mL). CONCLUSION Leptin exerts a stimulatory effect on the proliferation and chondrogenic differentiation of the long bone growth plate but an inhibitory effect on the spine growth plate. The ongoing study will shed light on the regulatory mechanisms of leptin in bone development and metabolism.
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Affiliation(s)
- Bo Yu
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China
| | - Kaibiao Jiang
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China
| | - Bin Chen
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China
| | - Hantao Wang
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China
| | - Xinfeng Li
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China
| | - Zude Liu
- Department of Spine Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Rd, Shanghai, 200127, China.
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Halverson SJ, Warhoover T, Mencio GA, Lovejoy SA, Martus JE, Schoenecker JG. Leptin Elevation as a Risk Factor for Slipped Capital Femoral Epiphysis Independent of Obesity Status. J Bone Joint Surg Am 2017; 99:865-872. [PMID: 28509827 PMCID: PMC5426400 DOI: 10.2106/jbjs.16.00718] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Slipped capital femoral epiphysis (SCFE) is strongly associated with childhood obesity, yet the prevalence of obesity is orders of magnitude greater than the prevalence of SCFE. Therefore, it is hypothesized that obesity is not, by itself, a sufficient condition for SCFE, but rather one component of a multifactorial process requiring preexisting physeal pathology. Leptin elevation is seen to varying degrees in patients with obesity, and as leptin has been shown to cause physeal pathology similar to the changes seen in SCFE, we propose that leptin may be a factor distinguishing between patients with SCFE and equally obese children without hip abnormalities. METHODS Serum leptin levels were obtained from 40 patients with SCFE and 30 control patients with approximate body mass index (BMI) matching. BMI percentiles were calculated according to Centers for Disease Control and Prevention population data by patient age and sex. Patients were compared by demographic characteristics, leptin levels, odds of leptin elevation, and odds of SCFE. RESULTS The odds of developing SCFE was increased by an odds ratio of 4.9 (95% confidence interval [CI], 1.31 to 18.48; p < 0.02) in patients with elevated leptin levels, regardless of obesity status, sex, and race. When grouping patients by their obesity status, non-obese patients with SCFE showed elevated median leptin levels at 5.8 ng/mL compared with non-obese controls at 1.7 ng/mL (p = 0.006). Similarly, obese patients with SCFE showed elevated median leptin levels at 17.9 ng/mL compared with equally obese controls at 10.5 ng/mL (p = 0.039). Serum leptin levels increased in association with obesity (p < 0.001), with an increase in leptin of 0.17 ng/mL (95% CI, 0.07 to 0.27 ng/mL) per BMI percentile point. CONCLUSIONS To our knowledge, this study is the first to clinically demonstrate an association between elevated serum leptin levels and SCFE, regardless of BMI. This adds to existing literature suggesting that SCFE is a multifactorial process and that leptin levels may have profound physiological effects on the development of various disease states. Despite a strong association with adiposity, leptin levels vary between patients of equal BMI and may be a vital resource in prognostication of future obesity-related comorbidities. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Schuyler J. Halverson
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee
| | - Tracy Warhoover
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee
| | - Gregory A. Mencio
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee
| | - Steven A. Lovejoy
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee
| | - Jeffrey E. Martus
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee
| | - Jonathan G. Schoenecker
- Monroe Carell Jr. Children’s Hospital at Vanderbilt Medical Center, Nashville, Tennessee,E-mail address for J.G. Schoenecker:
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Leptin Receptor Metabolism Disorder in Primary Chondrocytes from Adolescent Idiopathic Scoliosis Girls. Int J Mol Sci 2016; 17:ijms17071160. [PMID: 27447624 PMCID: PMC4964532 DOI: 10.3390/ijms17071160] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/27/2016] [Accepted: 07/11/2016] [Indexed: 01/22/2023] Open
Abstract
To investigate the underlying mechanisms of low metabolic activity of primary chondrocytes obtained from girls with adolescent idiopathic scoliosis (AIS); AIS is a spine-deforming disease that often occurs in girls. AIS is associated with a lower bone mass than that of healthy individuals and osteopenia. Leptin was shown to play an important role in bone growth. It can also regulate the function of chondrocytes. Changes in leptin and Ob-R levels in AIS patients have been reported in several studies. The underlying mechanisms between the dysfunction of peripheral leptin signaling and abnormal chondrocytes remain unclear; The following parameters were evaluated in AIS patients and the control groups: total serum leptin levels; Ob-R expression in the plasma membrane of primary chondrocytes; JAK2 and STAT3 phosphorylation status. Then, we inhibited the lysosome and proteasome and knocked down clathrin heavy chain (CHC) expression in primary chondrocytes isolated from girls with AIS and evaluated Ob-R expression. We investigated the effects of leptin combined with a lysosome inhibitor or CHC knockdown in primary chondrocytes obtained from AIS patients; Compared with the controls, AIS patients showed similar total serum leptin levels, reduced JAK2 and STAT3 phosphorylation, and decreased cartilage matrix synthesis in the facet joint. Lower metabolic activity and lower membrane expression of Ob-R were observed in primary chondrocytes from the AIS group than in the controls. Lysosome inhibition increased the total Ob-R content but had no effect on the membrane expression of Ob-R or leptin’s effects on AIS primary chondrocytes. CHC knockdown upregulated the membrane Ob-R levels and enhanced leptin’s effects on AIS primary chondrocytes; The underlying mechanism of chondrocytes that are hyposensitive to leptin in some girls with AIS is low plasma membrane Ob-R expression that results from an imbalance between the rate of receptor endocytosis and the insertion of newly synthesized receptors into the membrane.
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Cooley J, Broderick TL, Al-Nakkash L, Plochocki JH. Effects of resveratrol treatment on bone and cartilage in obese diabetic mice. J Diabetes Metab Disord 2015; 14:10. [PMID: 25789256 PMCID: PMC4363196 DOI: 10.1186/s40200-015-0141-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 02/23/2015] [Indexed: 12/23/2022]
Abstract
Background Resveratrol is a polyphenolic phytoalexin that has been shown to exhibit osteoprotective and chondroprotective properties. We examine the effects of resveratrol treatment on bone and cartilage tissue of obese, diabetic ob/ob mice. Methods Eight-week-old ob/ob and lean control mice were given trans-resveratrol at an oral dose of 25 mg/kg for 3 weeks. Histomorphometric and cross-sectional-geometric variables were analyzed. Results Ob/ob mice in our study exhibit significantly reduced femoral length, resistance to loading, and tibial growth plate total area and calcified area than lean controls (P < 0.05). Resveratrol treatment significantly increased cortical area in both ob/ob and control mice, but did not improve cross-sectional indicators of resistance to bending. Resveratrol treatment also reduced tibial length and calcified growth plate cartilage area in comparison to untreated mice (P < 0.05). Conclusion Resveratrol treatment of ob/ob mice had mixed effects on bone histomorphometry at the femoral midshaft. Treatment increased cortical area but decreased bone length.
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Affiliation(s)
- Joseph Cooley
- Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ USA
| | - Tom L Broderick
- Departent of Physiology, Laboratory of Diabetes and Exercise Metabolism, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ USA
| | - Layla Al-Nakkash
- Departent of Physiology, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ USA
| | - Jeffrey H Plochocki
- Department of Anatomy, Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ USA
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Gat-Yablonski G, Phillip M. Nutritionally-induced catch-up growth. Nutrients 2015; 7:517-51. [PMID: 25594438 PMCID: PMC4303852 DOI: 10.3390/nu7010517] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 12/31/2014] [Indexed: 12/17/2022] Open
Abstract
Malnutrition is considered a leading cause of growth attenuation in children. When food is replenished, spontaneous catch-up (CU) growth usually occurs, bringing the child back to its original growth trajectory. However, in some cases, the CU growth is not complete, leading to a permanent growth deficit. This review summarizes our current knowledge regarding the mechanism regulating nutrition and growth, including systemic factors, such as insulin, growth hormone, insulin- like growth factor-1, vitamin D, fibroblast growth factor-21, etc., and local mechanisms, including autophagy, as well as regulators of transcription, protein synthesis, miRNAs and epigenetics. Studying the molecular mechanisms regulating CU growth may lead to the establishment of better nutritional and therapeutic regimens for more effective CU growth in children with malnutrition and growth abnormalities. It will be fascinating to follow this research in the coming years and to translate the knowledge gained to clinical benefit.
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Affiliation(s)
- Galia Gat-Yablonski
- The Jesse Z and Sara Lea Shafer Institute for Endocrinology and Diabetes, National Center for Children's Diabetes, Schneider Children's Medical Center of Israel, and Felsenstein Medical Research Center, Petach Tikva 49100, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
| | - Moshe Phillip
- The Jesse Z and Sara Lea Shafer Institute for Endocrinology and Diabetes, National Center for Children's Diabetes, Schneider Children's Medical Center of Israel, and Felsenstein Medical Research Center, Petach Tikva 49100, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
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15
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Abstract
Nutritional status is an essential component in determining whole body energy homeostasis. The balance between energy/food intake and metabolism is governed by a range of hormones secreted from various parts of the body. Their subsequent dissemination via the blood results in a wide range of biological responses including satiety, hunger, and glucose uptake. The roles of these systemic hormones also extend to bone regulation with animal and clinical studies establishing a relationship between these regulatory pathways. This review covers the gastrointestinal hormones, ghrelin, PYY, GIP, GLP-1, and GLP-2, and the adipokines, leptin, and adiponectin and their roles in regulating bone homeostasis. Their known actions are reviewed, with an emphasis upon recent advances in understanding. Taken together, this review outlines an expanding appreciation of the interactions between bone mass and the nutritional control of whole body energy balance by gut and adipose tissue.
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Affiliation(s)
- Ee Cheng Khor
- Bone Regulation, Neuroscience Research Division, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, New South Wales, 2010, Australia
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16
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Li XF, Wang SJ, Jiang LS, Dai LY. Stage specific effect of leptin on the expressions of estrogen receptor and extracellular matrix in a model of chondrocyte differentiation. Cytokine 2013; 61:876-84. [PMID: 23357303 DOI: 10.1016/j.cyto.2012.12.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 11/20/2012] [Accepted: 12/19/2012] [Indexed: 01/01/2023]
Abstract
Endochondral ossification is a dynamic process. The interaction between leptin and estrogen in this process is complicated. Whether there is a stage specific crosstalk between leptin and estrogen in the differentiation process of the chondrocytes in the growth plate remains unknown. The aim of our study was to investigate the effect of leptin on the expression of estrogen receptors and extracellular matrix in ATDC5 cells, an in vitro model of endochondral ossification. First, we quantified the physiological expressions of estrogen receptors α, β (ERα, ERβ), leptin receptor (Ob-Rb), type II and type X collagens in definite stages of endochondral ossification in ATDC5 cells using real-time PCR. Dynamic and stage specific expression characteristics of these target genes were observed. Simultaneous expressions of Ob-Rb with ERα or ERβ in ATDC5 cells were also found with dual-label confocal immunofluorescency. Then using Western blotting analysis and/or real-time PCR, we detected that, leptin treatment up-regulated the expressions of ERα, ERβ and type II collagen, but down-regulated type X collagen expression and the ERα/ERβ ratio in the chondrogenic differentiation stage. Meanwhile, leptin down-regulated the expressions of ERα, type II and type X collagens, and the ERα/ERβ ratio, but up-regulated the expression of ERβ in the hypertrophic differentiation stage. Significant positive correlation existed between ERα and type II collagen expression, and between the ratio of ERα/ERβ and type X collagen production. In summary, the crosstalk between leptin and estrogen receptor might be differentiation stage specific in ATDC5 cells.
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Affiliation(s)
- Xin-Feng Li
- Department of Orthopaedic Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
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17
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Amelio PD, Panico A, Spertino E, Isaia GC. Energy metabolism and the skeleton: Reciprocal interplay. World J Orthop 2012; 3:190-8. [PMID: 23330074 PMCID: PMC3547113 DOI: 10.5312/wjo.v3.i11.190] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 07/31/2012] [Accepted: 10/20/2012] [Indexed: 02/06/2023] Open
Abstract
The relation between bone remodelling and energy expenditure is an intriguing, and yet unexplained, challenge of the past ten years. In fact, it was only in the last few years that the skeleton was found to function, not only in its obvious roles of body support and protection, but also as an important part of the endocrine system. In particular, bone produces different hormones, like osteocalcin (OC), which influences energy expenditure in humans. The undercarboxylated form of OC has a reduced affinity for hydroxyapatite; hence it enters the systemic circulation more easily and exerts its metabolic functions for the proliferation of pancreatic β-cells, insulin secretion, sensitivity, and glucose tolerance. Leptin, a hormone synthesized by adipocytes, also has an effect on both bone remodelling and energy expenditure; in fact it inhibits appetite through hypothalamic influence and, in bone, stimulates osteoblastic differentiation and inhibits apoptosis. Leptin and serotonin exert opposite influences on bone mass accrual, but several features suggest that they might operate in the same pathway through a sympathetic tone. Serotonin, in fact, acts via two opposite pathways in controlling bone remodelling: central and peripheral. Serotonin product by the gastrointestinal tract (95%) augments bone formation by osteoblast, whereas brain-derived serotonin influences low bone mineral density and its decrease leads to an increase in bone resorption parameters. Finally, amylin (AMY) acts as a hormone that alters physiological responses related to feeding, and plays a role as a growth factor in bone. In vitro AMY stimulates the proliferation of osteoblasts, and osteoclast differentiation. Here we summarize the evidence that links energy expenditure and bone remodelling, with particular regard to humans.
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18
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Wang SJ, Li XF, Jiang LS, Dai LY. Leptin regulates estrogen receptor gene expression in ATDC5 cells through the extracellular signal regulated kinase signaling pathway. J Cell Biochem 2012; 113:1323-32. [PMID: 22135239 DOI: 10.1002/jcb.24005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Both estrogen and leptin play an important role in the regulation of physiological processes of endochondral bone formation in linear growth. Estrogen receptors (ERα and ERβ) are known as members of the superfamily of nuclear steroid hormone receptors and are detected in all zones of growth plate chondrocytes. They can be regulated in a ligand-independent manner. Whether leptin regulates ERs in the growth plate is still not clear. To explore this issue, chondrogenic ATDC5 cells were used in the present study. Messenger RNA and protein analyses were performed by quantitative PCR and Western blotting. We found that both ERα and ERβ were dynamically expressed during the ATDC5 cell differentiation for 21 days. Leptin (50 ng/ml) significantly upregulated ERα and ERβ mRNA and protein levels 48 h after leptin stimulation (P<0.05) at day 14. The up-regulation of ERα and ERβ mRNA by leptin was shown in a dose-dependent manner, but the most effective dose of leptin was different (100 and 1,000 ng/ml, respectively). Furthermore, we confirmed that leptin augmented the phosphorylation of ERK1/2 in a time-dependent manner. A maximum eightfold change was observed at 15 min. Finally, a specific ERK1/2 inhibitor, UO126, blocked leptin-induced ERs regulation in ATDC5 cells, indicating that ERK1/2 mediates, partly, the effects of leptin on ERs. These data demonstrate, for the first time, that leptin regulates the expression of ERs in growth plate chondrocytes via ERK signaling pathway, thereby suggesting a crosstalk between leptin and estrogen receptors in the regulation of bone formation.
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Affiliation(s)
- Shan-Jin Wang
- Department of Orthopedic Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
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19
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Wang SJ, Li XF, Jiang LS, Dai LY. Estrogen stimulates leptin receptor expression in ATDC5 cells via the estrogen receptor and extracellular signal-regulated kinase pathways. J Endocrinol 2012; 213:163-72. [PMID: 22396455 DOI: 10.1530/joe-11-0353] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Regulation of the physiological processes of endochondral bone formation during long bone growth is controlled by various factors including the hormones estrogen and leptin. The effects of estrogen are mediated not only through the direct activity of estrogen receptors (ERs) but also through cross talk with other signaling systems implicated in chondrogenesis. The receptors of both estrogen and leptin (OBR (LEPR)) are detectable in growth plate chondrocytes of all zones. In this study, the expression of mRNA and protein of OBR in chondrogenic ATDC5 cells and the effect of 17β-estradiol (E(2)) stimulation were assessed using quantitative PCR and western blotting. We have found that the mRNA of Obr was dynamically expressed during the differentiation of ATDC5 cells over 21 days. Application of E(2) (10(-7) M) at day 14 for 48 h significantly upregulated OBR mRNA and protein levels (P<0.05). The upregulation of Obr mRNA by E(2) was shown to take place in a concentration-dependent manner, with a concentration of 10(-7) M E(2) having the greatest effect. Furthermore, we have confirmed that E(2) affected the phosphorylation of ERK1/2 (MAPK1/MAPK3) in a time-dependent manner where a maximal fourfold change was observed at 10 min following application of E(2). Finally, pretreatment of the cells with either U0126 (ERK1/2 inhibitor) or ICI 182 780 (ER antagonist) blocked the upregulation of OBR by E(2) and prevented the E(2)-induced phosphorylation of ERK. These data demonstrate, for the first time, the existence of cross talk between estrogen and OBR in the regulation of bone growth whereby estrogen regulates the expression of Obr in growth plate chondrocytes via ERs and the activation of ERK1/2 signaling pathways.
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Affiliation(s)
- Shan-Jin Wang
- Department of Orthopedic Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, 1665 Kongjiang Road, Shanghai 200092, China
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20
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Hübner S, Efthymiadis A. Recent progress in histochemistry and cell biology. Histochem Cell Biol 2012; 137:403-57. [PMID: 22366957 DOI: 10.1007/s00418-012-0933-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2012] [Indexed: 01/06/2023]
Abstract
Studies published in Histochemistry and Cell Biology in the year 2011 represent once more a manifest of established and newly sophisticated techniques being exploited to put tissue- and cell type-specific molecules into a functional context. The review is therefore the Histochemistry and Cell Biology's yearly intention to provide interested readers appropriate summaries of investigations touching the areas of tissue biology, developmental biology, the biology of the immune system, stem cell research, the biology of subcellular compartments, in order to put the message of such studies into natural scientific-/human- and also pathological-relevant correlations.
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Affiliation(s)
- Stefan Hübner
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.
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21
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Gat-Yablonski G, Yackobovitch-Gavan M, Phillip M. Nutrition and bone growth in pediatrics. Pediatr Clin North Am 2011; 58:1117-40, ix. [PMID: 21981952 DOI: 10.1016/j.pcl.2011.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Children's growth is a hallmark of their normal development and the association between nutrition and linear growth in children is well accepted. Growth requires an adequate supply of many different nutritional factors, some form the "building materials," whereas others play regulatory roles. In this article we describe the growth of the growth plate and discuss the role of nutritional affected hormones on this process. In addition we describe the effect of local regulators and nutritional factors on the growth process and suggest the involvement of new regulatory factors in the translation of nutrition to growth.
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Affiliation(s)
- Galia Gat-Yablonski
- The Jesse Z. and Sara Lea Shafer Institute for Endocrinology and Diabetes, National Center for Childhood Diabetes, Schneider Children's Medical Center of Israel, 14 Kaplan Street, Petah Tikva 49202, Israel
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22
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Iwaniec UT, Boghossian S, Trevisiol CH, Wronski TJ, Turner RT, Kalra SP. Hypothalamic leptin gene therapy prevents weight gain without long-term detrimental effects on bone in growing and skeletally mature female rats. J Bone Miner Res 2011; 26:1506-16. [PMID: 21328617 PMCID: PMC3129999 DOI: 10.1002/jbmr.365] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Hypothalamic leptin gene therapy normalizes the mosaic skeletal phenotype of leptin-deficient ob/ob mice. However, it is not clear whether increased hypothalamic leptin alters bone metabolism in animals already producing the hormone. The objective of this study was to evaluate the long duration effects of recombinant adeno-associated virus-rat leptin (rAAV-Lep) hypothalamic gene therapy on weight gain and bone metabolism in growing and skeletally mature leptin-replete female Sprague-Dawley rats. Rats were either unoperated or implanted with cannulas in the third ventricle of the hypothalamus and injected with either rAAV-Lep or rAAV-GFP (control vector encoding green fluorescent protein) and maintained on standard rat chow fed ad libitum for either 5 or 10 weeks (starting at 3 months of age) or 18 weeks (starting at 9 months of age). Tibias, femurs, or lumbar vertebrae were analyzed by micro-computed tomography and/or histomorphometry. In comparison with age-matched rAAV-GFP rats, rAAV-Lep rats maintained a lower body weight for the duration of studies. At 5 weeks after vector administration, rAAV-Lep rats had lower cancellous bone volume and bone marrow adiposity but higher osteoblast perimeter compared with nonoperated controls. However, these values did not differ between the two groups at 10 weeks after vector administration. Differences in cancellous bone volume and architecture were not detected between the rAAV-Lep and rAAV-GFP groups at either time point. Also, rAAV-Lep had no negative effects on bone in the 9-month-old skeletally mature rats at 18 weeks after vector administration. We hypothesize that the transient reductions in bone mass and bone marrow adiposity at 5 weeks after vector administration were due to hypothalamic surgery. We conclude that increased hypothalamic leptin, sufficient to prevent weight gain, has minimal specific effects (rAAV-Lep versus rAAV-GFP) on bone metabolism in normal female rats.
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Affiliation(s)
- Urszula T Iwaniec
- Department of Nutrition and Exercise Sciences, Oregon State University, Corvallis, OR 97331, USA.
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23
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Wang L, Shao YY, Ballock RT. Leptin synergizes with thyroid hormone signaling in promoting growth plate chondrocyte proliferation and terminal differentiation in vitro. Bone 2011; 48:1022-7. [PMID: 21349356 DOI: 10.1016/j.bone.2011.02.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 02/14/2011] [Accepted: 02/15/2011] [Indexed: 12/22/2022]
Abstract
Leptin and thyroid hormone are two hormones that regulate energy balance through central signaling mechanisms. Recent studies in leptin-deficient ob/ob mice indicate that leptin also has peripheral effects in modulating the function of the growth plate, perhaps in terms of proliferation and differentiation enhancement. Thyroid hormone has been well-described as a potent stimulator of growth plate chondrocyte maturation. The objective of this study was therefore to investigate the interaction between leptin and thyroid hormone signaling in growth plate chondrocyte proliferation and terminal differentiation. Our in vitro data demonstrate that leptin synergistically functions with thyroid hormone through activation of both IGF-1/IGF1R signaling and Wnt/β-catenin signaling, two pathways that have been previously described as downstream effectors of thyroid hormone action. Leptin increases thyroid hormone receptor-α (TRα) expression and thyroid hormone receptor transcriptional activity. Thyroid hormone also activates leptin signaling in growth plate cells undergoing proliferation and hypertrophy. We conclude that leptin synergically interacts with thyroid hormone in promoting growth plate chondrocyte proliferation and terminal differentiation.
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Affiliation(s)
- Lai Wang
- Department of Biomedical Engineering, The Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, USA.
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24
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Li XF, Yan J, Jiang LS, Dai LY. Age-related variations of leptin receptor expression in the growth plate of spine and limb: gender- and region-specific changes. Histochem Cell Biol 2011; 135:487-97. [PMID: 21452040 DOI: 10.1007/s00418-011-0805-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2011] [Indexed: 01/17/2023]
Abstract
Leptin is a potent growth-stimulating factor of bone. The effects of leptin on bone growth differ significantly between axial and appendicular regions. Gender differences of leptin function have also been suggested in normal pubertal development. To explore the mechanisms underlying these effects, we investigated the spatial and temporal expressions of the active form of the leptin receptor (Ob-Rb) in the tibial and spinal growth plates of the female and male rats during postnatal development. The 1-, 4-, 7-, 12- and 16-week age stages are representative for early life, puberty and early adulthood after puberty, respectively. Quantitative real-time PCR was used for Ob-Rb mRNA examination and comparison. The spatial location of Ob-Rb was determined by immunohistochemical analysis. There were gender- and region-specific differences in Ob-Rb mRNA expression in the growth plate. Mainly cytoplasm staining of Ob-Rb immunoreactivity was observed in the spinal and tibial growth plate chondrocytes of both genders. Spatial differences of region- and gender-related Ob-Rb expression were not observed. Ob-Rb immunoreactivity was detected in the resting, proliferative and prehypertrophic chondrocytes in early life stage and during puberty. After puberty, staining was mainly located in the late proliferative and hypertrophic chondrocytes. The results of Ob-Rb HSCORE analysis were similar to those obtained from quantitative real-time PCR. Our study indicated direct effects on the chondrocytes of the growth plate in different development stages. The region-specific expression patterns of Ob-Rb gene might be one possible reason for contrasting phenotypes in limb and spine. Different Ob-Rb expression patterns might partly contribute to age- and gender- related differences in trabecular bone mass.
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Affiliation(s)
- Xin-Feng Li
- Department of Orthopedic Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, 1665 Kongjiang Road, 200092, Shanghai, China
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25
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Ohba S, Lanigan TM, Roessler BJ. Leptin receptor JAK2/STAT3 signaling modulates expression of Frizzled receptors in articular chondrocytes. Osteoarthritis Cartilage 2010; 18:1620-9. [PMID: 20868760 PMCID: PMC2997121 DOI: 10.1016/j.joca.2010.09.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 09/13/2010] [Accepted: 09/14/2010] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Differentiated articular chondrocytes express a functional bisoform of the leptin receptor (LRb); however, leptin-LRb signaling in these cells is poorly understood. We hypothesized that leptin-LRb signaling in articular chondrocytes functions to modulate canonical Wnt signaling events by altering the expression of Frizzled (FZD) receptors. METHODS Human chondrocyte cell lines and primary articular chondrocytes were grown in serum containing growth media for 24h, followed by a media change to Dulbecco's modified Eagle's medium (DMEM) containing 1% Nutridoma-SP to obtain a serum-deficient environment for 24h before treatment. Treatments included recombinant human leptin (10-100nM), recombinant human IL-6 (0.3-3nM), or recombinant human erythropoietin (Epo) (10mU/ml). Cells were harvested 30min-48h after treatment and whole cell lysates were analyzed using immunoblots or luciferase assays. RESULTS Treatment of cells with leptin resulted in activation of Janus kinase 2 (JAK2) and subsequent phosphorylation of specific tyrosine residues on LRb, followed by dose- and time-dependent increases in the expression of Frizzled-1 (FZD1) and Frizzled-7 (FZD7). Leptin-mediated increases in the expression of FZD1 were blocked by pre-treatment with the protein synthesis inhibitor cycloheximide or the JAK2 inhibitor AG490. Experiments using a series of hybrid Epo extracellular domain-leptin intracellular domain receptors (ELR) harboring mutations of specific tyrosine residues in the cytoplasmic tail showed that increases in the expression of FZD1 were dependent on LRb-mediated phosphorylation of STAT3, but not ERK1/2 or STAT5. Leptin pre-treatment of chondrocytes prior to Wnt3a stimulation resulted in an increased magnitude of canonical Wnt signaling. CONCLUSION These experiments show that leptin-LRb signaling in articular chondrocytes modulates expression of canonical Wnt signaling receptors and suggests that direct cross-talk between these pathways is important in determining chondrocyte homeostasis.
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Affiliation(s)
- Seigo Ohba
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109-5688
| | - Thomas M. Lanigan
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109-5688
| | - Blake J. Roessler
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109-5688
- To whom correspondence should be addressed: 3560 MSRB2, 1150 W. Medical Center Dr., Ann Arbor, MI 48109-5688, Tel.: 734-763-7949, Fax: 734-764-3596,
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26
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Hu PF, Bao JP, Wu LD. The emerging role of adipokines in osteoarthritis: a narrative review. Mol Biol Rep 2010; 38:873-8. [PMID: 20480243 DOI: 10.1007/s11033-010-0179-y] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 05/06/2010] [Indexed: 01/15/2023]
Abstract
Osteoarthritis (OA) is a most common multifactorial degenerative joint disease in elderly individuals. OA is affecting severely the quality of life of patients, while the causes of OA are not completely understood. Age, obesity, the female sex, and previous injury are considered as significant risk factors. Recently, increased levels of adipokines which are mainly produced by adipocytes have been detected in patients with osteoarthritis. Moreover, studies on different adipokines all reveal that they have played proinflammatory and catabolic/anabolic roles during the pathophysiology of OA. In the present review, we summarize current data on the effect of the adipose tissue-derived hormones leptin, adiponectin, resistin and visfatin on initiation and progression of OA.
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Affiliation(s)
- Peng-fei Hu
- Zhejiang University College of Medicine, Hangzhou, People's Republic of China
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27
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Burwell RG, Aujla RK, Grevitt MP, Dangerfield PH, Moulton A, Randell TL, Anderson SI. Pathogenesis of adolescent idiopathic scoliosis in girls - a double neuro-osseous theory involving disharmony between two nervous systems, somatic and autonomic expressed in the spine and trunk: possible dependency on sympathetic nervous system and hormones with implications for medical therapy. SCOLIOSIS 2009; 4:24. [PMID: 19878575 PMCID: PMC2781798 DOI: 10.1186/1748-7161-4-24] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2009] [Accepted: 10/31/2009] [Indexed: 12/24/2022]
Abstract
Anthropometric data from three groups of adolescent girls - preoperative adolescent idiopathic scoliosis (AIS), screened for scoliosis and normals were analysed by comparing skeletal data between higher and lower body mass index subsets. Unexpected findings for each of skeletal maturation, asymmetries and overgrowth are not explained by prevailing theories of AIS pathogenesis. A speculative pathogenetic theory for girls is formulated after surveying evidence including: (1) the thoracospinal concept for right thoracic AIS in girls; (2) the new neuroskeletal biology relating the sympathetic nervous system to bone formation/resorption and bone growth; (3) white adipose tissue storing triglycerides and the adiposity hormone leptin which functions as satiety hormone and sentinel of energy balance to the hypothalamus for long-term adiposity; and (4) central leptin resistance in obesity and possibly in healthy females. The new theory states that AIS in girls results from developmental disharmony expressed in spine and trunk between autonomic and somatic nervous systems. The autonomic component of this double neuro-osseous theory for AIS pathogenesis in girls involves selectively increased sensitivity of the hypothalamus to circulating leptin (genetically-determined up-regulation possibly involving inhibitory or sensitizing intracellular molecules, such as SOC3, PTP-1B and SH2B1 respectively), with asymmetry as an adverse response (hormesis); this asymmetry is routed bilaterally via the sympathetic nervous system to the growing axial skeleton where it may initiate the scoliosis deformity (leptin-hypothalamic-sympathetic nervous system concept = LHS concept). In some younger preoperative AIS girls, the hypothalamic up-regulation to circulating leptin also involves the somatotropic (growth hormone/IGF) axis which exaggerates the sympathetically-induced asymmetric skeletal effects and contributes to curve progression, a concept with therapeutic implications. In the somatic nervous system, dysfunction of a postural mechanism involving the CNS body schema fails to control, or may induce, the spinal deformity of AIS in girls (escalator concept). Biomechanical factors affecting ribs and/or vertebrae and spinal cord during growth may localize AIS to the thoracic spine and contribute to sagittal spinal shape alterations. The developmental disharmony in spine and trunk is compounded by any osteopenia, biomechanical spinal growth modulation, disc degeneration and platelet calmodulin dysfunction. Methods for testing the theory are outlined. Implications are discussed for neuroendocrine dysfunctions, osteopontin, sympathoactivation, medical therapy, Rett and Prader-Willi syndromes, infantile idiopathic scoliosis, and human evolution. AIS pathogenesis in girls is predicated on two putative normal mechanisms involved in trunk growth, each acquired in evolution and unique to humans.
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Affiliation(s)
- R Geoffrey Burwell
- Centre for Spinal Studies and Surgery, Nottingham University Hospitals Trust, Queen's Medical Centre Campus, Nottingham, UK
| | - Ranjit K Aujla
- Centre for Spinal Studies and Surgery, Nottingham University Hospitals Trust, Queen's Medical Centre Campus, Nottingham, UK
| | - Michael P Grevitt
- Centre for Spinal Studies and Surgery, Nottingham University Hospitals Trust, Queen's Medical Centre Campus, Nottingham, UK
| | | | - Alan Moulton
- Department of Orthopaedic Surgery, King's Mill Hospital, Mansfield, UK
| | - Tabitha L Randell
- Department of Child Health, Nottingham University Hospitals Trust, Queen's Medical Centre Campus, Nottingham, UK
| | - Susan I Anderson
- School of Biomedical Sciences, University of Nottingham, Nottingham, UK
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28
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Gat-Yablonski G, Yackobovitch-Gavan M, Phillip M. Nutrition and bone growth in pediatrics. Endocrinol Metab Clin North Am 2009; 38:565-86. [PMID: 19717005 DOI: 10.1016/j.ecl.2009.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Children's growth is a hallmark of their normal development and the association between nutrition and linear growth in children is well accepted. Growth requires an adequate supply of many different nutritional factors, some form the "building materials," whereas others play regulatory roles. In this article we describe the growth of the growth plate and discuss the role of nutritional affected hormones on this process. In addition we describe the effect of local regulators and nutritional factors on the growth process and suggest the involvement of new regulatory factors in the translation of nutrition to growth.
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Affiliation(s)
- Galia Gat-Yablonski
- The Jesse Z. and Sara Lea Shafer Institute for Endocrinology and Diabetes, National Center for Childhood Diabetes, Schneider Children's Medical Center of Israel, 14 Kaplan Street, Petah Tikva 49202, Israel
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29
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Changes in lipid metabolism associated gene transcripts during porcine adipogenesis. Comp Biochem Physiol B Biochem Mol Biol 2009; 153:8-17. [DOI: 10.1016/j.cbpb.2008.12.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 12/23/2008] [Accepted: 12/31/2008] [Indexed: 11/20/2022]
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Heep H, Hilken G, Hofmeister S, Wedemeyer C. Osteoarthitis of leptin-deficient ob/ob mice in response to biomechanical loading in micro-CT. Int J Biol Sci 2009; 5:265-75. [PMID: 19343112 PMCID: PMC2664549 DOI: 10.7150/ijbs.5.265] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Accepted: 03/14/2009] [Indexed: 01/31/2023] Open
Abstract
Objective: Mechanotransduction is the mechanism that due to reacting chondrocytes on biomechanical loading of body mass. Higher biomechanical loading lead to increased degeneration of chondrocytes, whereas moderate loading is protecting. This suggests that body fat regulates bone metabolism first by means of hormonal factors and second that the effects of muscle and loading are signaling factors in mechanotransduction. Leptin, a peptide hormone produced predominantly by white fat cells, is one of these hormonal factors. The aim of this study was to investigate and measure the different effects of weight-bearing on trabecular bone formation in mice without the stimulation of leptin and with or without osteoarthritis. Materials and methods: 40 C57BL/ 6J ob/ob-mice in the age of 20 weeks have been devided into two groups with an ad-libitum-diet and with reduced diet. The hip- and knee-joints have been examinated in micro-CT-scan and histomorphologically. Results: Animals with an ad-libitum-diet were found to increase body weight significantly at the age of six weeks in comparison with lean mice. At the age of twenty weeks the obese mice were almost twice as heavy as the lean mice. Significant statistical differences are shown between the two groups for body weight and bone mineral density. Examination of trabecular bone in micro-CT revealed that the only statistically significant difference between the two groups was the trabecular number for the proximal femur. High weight-bearing insignificantly improved all trabecular bone parameters in the obese mice. Correlation was found between trabecular number and bone mineral density on the one hand and body weight on the other hand. The correlation between body weight and osteoarthritis shows a significant increase in grade of osteoarthritis as body weight increases in hip-joint and knee-joint but not in osteoarthritis-positive (OP) versus osteoarthritis-negative (ON) mices. The correlation of the hip-joint between micro-CT data and body weight shows an increase in these data as body weight increases in OP mices. The correlation of the hip-joint between micro-CT data and osteoarthritis shows a decrease in these data as osteoarthritis increases in OP mices. The correlation of the knee-joint between micro-CT data and body weight shows differencies between ON and OP mices. The correlation of the knee-joint between micro-CT data and osteoarthritis shows an increase in these data as osteoarthritis increases in OP mices. Conclusion: biomechanical loading led to decreased bone mineral density by a decrease in the number of trabeculae. Trabecular thickness was not increased by biomechanical loading in growing mice. Decreased body weight in leptin-deficient mice protects against bone loss. This finding is consistent with the principle of light-weight construction of bone. Differences in osteoarthritis-positive and osteoarthritis-negative mices show the eventual importance of diet in leptin-deficience. It is not possible to conclude that these results also apply to human beings.
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Affiliation(s)
- Hansjoerg Heep
- Department of Orthopaedics, University of Duisburg-Essen, Pattbergstrasse, Germany.
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Expression of leptin and its functional receptor on disc cells: contribution to cell proliferation. Spine (Phila Pa 1976) 2008; 33:E858-64. [PMID: 18978578 DOI: 10.1097/brs.0b013e31818338e5] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Human herniated disc tissues and rat nucleus pulposus (NP) cells were used following approval by the authors' institutional Human Ethics Review Committee and Animal Care and Use Committee. OBJECTIVE To determine the expression of leptin and its functional receptor in herniated disc tissues, and to elucidate whether leptin can stimulate rat NP cells to proliferate in vitro. SUMMARY OF BACKGROUND DATA There is evidence showing that chondrocytes express leptin and functional leptin receptor, and leptin stimulates chondrocyte proliferation in vitro and may play a role in the pathogenesis of osteoarthritis by contributing to osteophyte formation. Intervertebral disc degeneration, similar to osteoarthritis, is also a complicated process in which increased cell proliferation is involved. However, little attention has been paid to the causes of the increased cell proliferation during disc degeneration. METHODS Forty-five herniated discs were harvested and immunostained to determine the distribution and type of leptin/functional leptin receptor-expressing cells. The proliferating activity of rat NP cells stimulated with leptin was also evaluated by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and by immunostaining for proliferation cell nuclear antigen (PCNA). RESULTS Immunohistochemical results from 45 herniated discs showed that leptin/functional leptin receptor-positive cells are commonly seen in cell clusters and proliferating fibrocartilaginous areas, and that the percentage of leptin/functional leptin receptor-positive cells correlates with the age of the patients. Leptin administration led to increased proliferation of rat NP cells in a dose-dependent manner, as shown by MTT assay and by counting the percentage of PCNA-positive cells. CONCLUSION Our results suggested that disc cells can express leptin and its functional receptor, that leptin can stimulate proliferation of disc cells in vitro, and therefore that leptin may play a role in the process of intervertebral disc degeneration by contributing to the formation of cell cluster and proliferating fibrocartilaginous tissue.
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Heep H, Wedemeyer C, Wegner A, Hofmeister S, von Knoch M. Differences in trabecular bone of leptin-deficient ob/ob mice in response to biomechanical loading. Int J Biol Sci 2008; 4:169-75. [PMID: 18566694 PMCID: PMC2430986 DOI: 10.7150/ijbs.4.169] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2008] [Accepted: 06/13/2008] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVE It is known that bone mineral density (BMD) and the strength of bone is predicted by body mass. Fat mass is a significant predictor of bone mineral density which correlates with body weight. This suggests that body fat regulates bone metabolism first by means of hormonal factors and second that the effects of muscle and loading are signaling factors in mechanotransduction. Leptin, a peptide hormone produced predominantly by white fat cells, is one of these hormonal factors. The aim of this study was to investigate and measure by micro-CT the different effects of weight-bearing on trabecular bone formation in mice without the stimulation of leptin. RESULTS Animals with an ad-libitum-diet (Group A) were found to increase body weight significantly at the age of six weeks in comparison with lean mice (Group B). From this point on, the difference increased constantly. At the age of twenty weeks the obese mice were almost twice as heavy as the lean mice. Significant statistical differences are shown between the two groups for body weight and bone mineral density. Examination of trabecular bone (BV/TV, trabecular number (Tb.N.), trabecular thickness (Tb.Th.)) revealed that the only statistically significant difference between the two groups was the Tb.N. for the proximal femur. High weight-bearing insignificantly improved all trabecular bone parameters in the obese mice. Compared with the control-diet Group B, the BV/TV and Tb.N. were slightly higher in the controlled-diet Group A, but not the Tb.Th.. However, correlation was found between Tb.N. and BMD on the one hand and body weight on the other hand. CONCLUSION biomechanical loading led to decreased bone mineral density by a decrease in the number of trabeculae. Trabecular thickness was not increased by biomechanical loading in growing mice. Decreased body weight in leptin-deficient mice protects against bone loss. This finding is consistent with the principle of light-weight construction of bone. Differences in cortical and trabecular bone will be examined in later studies. It is not possible to conclude that these results also apply to human beings.
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Affiliation(s)
- Hansjoerg Heep
- Department of Orthopaedics, University of Duisburg-Essen, Pattbergstrasse 1-3, 45239 Essen, Germany.
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Ben-Eliezer M, Phillip M, Gat-Yablonski G. Leptin regulates chondrogenic differentiation in ATDC5 cell-line through JAK/STAT and MAPK pathways. Endocrine 2007; 32:235-44. [PMID: 18080100 DOI: 10.1007/s12020-007-9025-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Revised: 07/23/2007] [Accepted: 09/12/2007] [Indexed: 12/19/2022]
Abstract
Leptin, the satiety hormone, has been found to affect growth-plate cartilage development. In the present study, some of the signal transduction pathways that mediate leptin signaling in the ATDC5 chondrogenic cell-line, a model for endochondral ossification, were analyzed. For this purpose, real-time PCR, Western blots and immunofluorescence techniques were used. It was found that leptin increased phosphorylation of ERK1/2, p38, and STAT3 in a time- and dose-dependent manner. Specific inhibition of STAT3 or ERK1/2, but not of P38, blocked the stimulatory effect of leptin on type X collagen mRNA levels. Moreover, leptin induced the translocation of ERK1/2 into the nucleus, as well as c-fos expression, indicating full activation of this cascade. Leptin-induced JNK phosphorylation was not observed, although leptin significantly and rapidly increased JNK protein levels and c-jun mRNA levels. In addition, ERK5 was identified in these cells, but there was no apparent effect of leptin on either its phosphorylation or protein level. The study indicates that the effects of leptin on growth-plate chondrocytes are specifically mediated through ERK1/2 and STAT3, while P38 is not essential for leptin-induced type X collagen expression. This is the first demonstration that these pathways are involved in leptin-induced growth.
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Affiliation(s)
- Miri Ben-Eliezer
- Felsenstein Medical Research Center, 14 Kaplan Street, Petach Tikva, 49202, Israel
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