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Fan G, Shi X, Huo C, Zuo H. Identifying critical genes and pathways of doxorubicin-induced cardiomyopathy via bioinformatics analysis. Eur Rev Med Pharmacol Sci 2024; 28:1641-1650. [PMID: 38497849 DOI: 10.26355/eurrev_202403_35578] [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] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
OBJECTIVE The pathogenesis of doxorubicin (DOX) induced cardiomyopathy (DCM) is still uncertain. We aimed to identify the critical genes and pathways involved in DCM based on bioinformatics analysis. MATERIALS AND METHODS The GSE59672 and GSE23598 mice heart tissue microarray data were obtained from Gene Expression Omnibus (GEO) database. The "limma" package of R software was used to screen the differently expressed genes (DEGs). GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analyses were performed on DEGs by using "clusterProfiler" package in R software. The PPI (Protein - Protein Interaction) network of DEGs constructed by STRING online database and thereby the top 15 hub genes selected by cytoHubba in Cytoscape software. The hub genes interaction was performed by GeneMANIA online database. The "Corrplot" R package was employed to assess hub genes correlation. RESULTS Finally, a total of 492 and 501 DEGs were screened in GSE59672 and GSE23598 datasets, respectively. GO analyses revealed that DEGs were mainly involved in the regulation of extracellular matrix organization, metabolic process, regulation of collagen-containing extracellular matrix. KEGG pathway analyses indicated that DEGs were mainly involved in protein digestion and absorption, ECM-receptor interaction, phagosome, and p53 signaling pathway. Finally, the 8 hub genes were identified, including Col1a1, Col3a1, Col1a2, Col6a1, Ptprc, Tyrobp, Itgb2, and Ctss. CONCLUSIONS The present study identified a series of key genes, including Col1a1, Col3a1, Col1a2, Col6a1, Ptprc, Tyrobp, Itgb2, and Ctss. In addition, important pathways were also discovered. The results of this study may provide a novel molecular mechanism and potential therapeutic targets for DCM.
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Affiliation(s)
- G Fan
- Cardiology Department, Xianyang Central Hospital, Xianyang, Shaanxi Province, China.
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Van Stan JH, Ortiz AJ, Sternad D, Mehta DD, Huo C, Hillman RE. Ambulatory Voice Biofeedback: Acquisition and Retention of Modified Daily Voice Use in Patients With Phonotraumatic Vocal Hyperfunction. Am J Speech Lang Pathol 2022; 31:409-418. [PMID: 34843372 PMCID: PMC9135013 DOI: 10.1044/2021_ajslp-21-00141] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/02/2021] [Accepted: 09/01/2021] [Indexed: 06/03/2023]
Abstract
PURPOSE Voice ambulatory biofeedback (VAB) has potential to improve carryover of therapeutic voice use into daily life. Previous work in vocally healthy participants demonstrated that motor learning inspired variations to VAB produced expected differences in acquisition and retention of modified daily voice use. This proof-of-concept study was designed to evaluate whether these VAB variations have the same desired effects on acquisition and retention in patients with phonotraumatic vocal hyperfunction (PVH). METHOD Seventeen female patients with PVH wore an ambulatory voice monitor for 6 days: three baseline days, one biofeedback day, one short-term retention day, and one long-term retention day. Short- and long-term retention were 1- and 7-days postbiofeedback, respectively. Patients were block-randomized to receive one of three types of VAB: 100%, 25%, and Summary. Performance was measured in terms of adherence time below a subject-specific vocal intensity threshold. RESULTS All three types of VAB produced a biofeedback effect with 13 out of 17 patients displaying an increase in adherence time compared to baseline days. Additionally, multiple patients from each VAB group increased their adherence time during short- and/or long-term retention monitoring compared to baseline. CONCLUSIONS These findings show that VAB can be associated with acquisition and retention of desired voice use in patients with PVH. Specifically, all three feedback types improved multiple patients' performance and retention for up to 1 week after biofeedback removal. Future work can investigate the impact of incorporating VAB into voice therapy.
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Affiliation(s)
- Jarrad H. Van Stan
- Massachusetts General Hospital, Boston
- Harvard Medical School, Boston, MA
- MGH Institute of Health Professions, Boston, MA
| | | | | | - Daryush D. Mehta
- Massachusetts General Hospital, Boston
- Harvard Medical School, Boston, MA
- MGH Institute of Health Professions, Boston, MA
| | - Chuanbing Huo
- Massachusetts General Hospital, Boston
- MGH Institute of Health Professions, Boston, MA
| | - Robert E. Hillman
- Massachusetts General Hospital, Boston
- Harvard Medical School, Boston, MA
- MGH Institute of Health Professions, Boston, MA
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Zhou Z, Ni J, Li J, Huo C, Miao N, Yin F, Cheng Q, Xu D, Xie H, Chen P, Zheng P, Zhang Y, Zhou L, Zhang W, Yu C, Liu J, Lu L. RIG-I aggravates interstitial fibrosis via c-Myc-mediated fibroblast activation in UUO mice. J Mol Med (Berl) 2020; 98:527-540. [PMID: 32036390 PMCID: PMC7198651 DOI: 10.1007/s00109-020-01879-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 01/06/2020] [Accepted: 01/16/2020] [Indexed: 01/14/2023]
Abstract
Abstract Progressive tubulointerstitial fibrosis is the common final outcome for all kidney diseases evolving into chronic kidney disease (CKD), whereas molecular mechanisms driving fibrogenesis remain elusive. Retinoic acid-inducible gene-I (RIG-I), an intracellular pattern recognition receptor, is originally identified participating in immune response by recognizing virus RNA. Here, we revealed for the first time that RIG-I was induced in unilateral ureteral obstruction (UUO) and folic acid (FA) renal fibrosis models and moderate-degree renal fibrosis patients. Besides, we found RIG-I was mainly located in renal tubular epithelial cells and promoted the production and release of inflammatory cytokines, such as interleukin (IL)-1β and IL-6 through activation of NF-κB. Inflammatory cytokines released by tubular epithelial cells activated c-Myc-mediated TGF-β/Smad signaling in fibroblasts, which in turn aggravated interstitial fibrosis by promoting fibroblast activation and production of extracellular matrix components (ECM). Deficiency of RIG-I attenuated renal fibrosis by the regulation of inflammatory responses, c-Myc expression, and fibroblast activation. Besides, gene silencing of RIG-I reduced inflammatory cytokines in cultured tubular epithelial cells treated with Angiotensin II. Knockdown of c-Myc or c-Myc inhibitor blocked IL-1β-induced fibroblast activation. Collectively, our study demonstrates that RIG-I plays a significant role in the progress of renal fibrosis via regulating c-Myc-mediated fibroblast activation. Key messages • RIG-I was constantly elevated in kidneys from renal fibrotic mice. • RIG-I facilitated inflammatory cytokine production in tubular epithelial cells. • RIG-I aggravated renal fibrosis via c-Myc-mediated TGF-β/Smad activation.
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Affiliation(s)
- Zhuanli Zhou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Jiayun Ni
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Jingyao Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Chuanbing Huo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Naijun Miao
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Fan Yin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Qian Cheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Dan Xu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Hongyan Xie
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Panpan Chen
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Peiqing Zheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Yingying Zhang
- Department of Nephrology, Tongji Hospital, Tongji University School of Medicine, Shanghai, 200065, China
| | - Li Zhou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Wei Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China
| | - Chen Yu
- Department of Nephrology, Tongji Hospital, Tongji University School of Medicine, Shanghai, 200065, China
| | - Jun Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China.
| | - Limin Lu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai, 200032, China.
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Du X, Li F, Lizee G, Hwu P, Deng L, Talukder A, Hawke D, Zou Q, Roszik J, Stairs M, Feng W, Jackson K, Chen C, Zhang M, Huo C, Chiu Y, Wang Y, Zhou S, Zhang Y, Xu J. Clinical study of personalized neoantigen peptide vaccination in advanced NSCLC patients. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz253.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Zhang F, Ma T, Cui P, Tamadon A, He S, Huo C, Yierfulati G, Xu X, Hu W, Li X, Shao LR, Guo H, Feng Y, Xu C. Diversity of the Gut Microbiota in Dihydrotestosterone-Induced PCOS Rats and the Pharmacologic Effects of Diane-35, Probiotics, and Berberine. Front Microbiol 2019; 10:175. [PMID: 30800111 PMCID: PMC6375883 DOI: 10.3389/fmicb.2019.00175] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 01/22/2019] [Indexed: 01/11/2023] Open
Abstract
Polycystic ovary syndrome (PCOS) is a frequent endocrine and metabolic syndrome in reproductive-age women. Recently, emerging evidence has shown that gut microbiota is closely related to metabolic diseases such as type 2 diabetes, obesity and PCOS. In the present study, we established dihydrotestosterone (DHT)-induced PCOS rats and used Illumina MiSeq sequencing (PE300) to examine the composition, diversity, and abundance of the gut microbiota in PCOS. We compared the effects of three PCOS treatments: Diane-35 (estrogen and progesterone), probiotics and berberine. The DHT-induced rats showed constant estrous cycles, the loss of mature ovarian follicles, insulin resistance and obesity. The reproductive and metabolic functions in the PCOS rats were improved by treatment with Diane-35 and probiotics. Diane-35 and probiotics could restore the diversity of the gut microbiota, and the recovery of gut microbiota disorders improved the reproductive function in PCOS-like rats. However, berberine drastically reduced the species diversity and amount of gut microbiota and showed no improvement in PCOS. The findings of this study will help us to better understand the influence of the gut microbiota in the metabolic and reproductive alterations in PCOS as well as suggest opportunities for future personal dietary guidance for PCOS.
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Affiliation(s)
- Feifei Zhang
- School of Public Health, Fudan University, Shanghai, China.,Obstetrics and Gynecology, Shanghai Medical College, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China
| | - Tong Ma
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Peng Cui
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Amin Tamadon
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Shan He
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Chuanbing Huo
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Gulinazi Yierfulati
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Xiaoqing Xu
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Wei Hu
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Xin Li
- Obstetrics and Gynecology, Shanghai Medical College, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China
| | - Linus R Shao
- Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Hongwei Guo
- School of Public Health, Fudan University, Shanghai, China
| | - Yi Feng
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institutes of Brain Science, Brain Science Collaborative Innovation Center, State Key Laboratory of Medical Neurobiology, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Congjian Xu
- Obstetrics and Gynecology, Shanghai Medical College, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, China
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Hou L, Lei Y, Li X, Huo C, Jia X, Yang J, Xu R, Wang X. Effect of Protein Supplementation Combined with Resistance Training on Muscle Mass, Strength and Function in the Elderly: A Systematic Review and Meta-Analysis. J Nutr Health Aging 2019; 23:451-458. [PMID: 31021362 DOI: 10.1007/s12603-019-1181-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND The loss of muscle mass, strength and function associated with increasing age has various health ramifications, including the elevated risk for falls, fractures, frailty, poor quality of life, and mortality. Several studies have confirmed the effects of protein supplementation and RT (resistance training) for this age-related change independently, but whether a combination of the two produces a stronger effect remains controversial. OBJECTIVE This study aims to explore whether a combination of protein supplementation and RT leads to reduction of muscle mass, strength and function in the elderly. METHODS We retrieved RCTs (randomized controlled trials) reporting the effects of protein supplementation combined with RT on muscle mass, strength and function in the elderly, published before May 2018 through PubMed, MEDLINE, Embase, and manual searches. RESULTS Twenty-one RCTs were included, involving 1,249 participants. The results showed that protein supplementation combine with RT significantly enhances the muscle mass and strength of the older adults, where FFM (fat-free mass) increased by 0.23 kg (95% CI: 0.09, 0.38; P=0.002), ASMM (appendicular skeletal muscle mass) by 0.39 kg (95% CI: 0.14, 0.64; P=0.002), handgrip strength by 0.29 kg (95% CI: 0.08, 0.50; P=0.008), knee extension strength by 0.27 kg (95% CI: 0.06, 0.47; P=0.013), leg press strength by 0.33 kg (95% CI: 0.01, 0.64; P=0.04), but no significant effects were seen on muscle function. CONCLUSION Compared to simple RT, protein supplementation combine with RT is more effective in enhancing the muscle mass and strength in the elderly, and the findings do not support the benefit of combination treatment for muscle function.
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Affiliation(s)
- L Hou
- Prof. Xiao-Ming Wang, Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China, E-mail: , Tel: +86-29-84775543
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Dou QP, Landis-Piwowar KR, Chen D, Huo C, Wan SB, Chan TH. Green tea polyphenols as a natural tumour cell proteasome inhibitor. Inflammopharmacology 2009; 16:208-12. [PMID: 18815743 DOI: 10.1007/s10787-008-8017-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cancer-preventive effects of green tea and its main constituent (-)-epigallocatechin gallate [(-)-EGCG] are widely supported by results from epidemiological, cell culture, animal and clinical studies although the molecular target has not been well defined. We previously reported that ester bond-containing tea polyphenols, e. g. (-)-EGCG, and their synthetic analogs potently and specifically inhibited the proteasomal activity. Subsequently, we further demonstrated that methylation on green tea polyphenols under physiological conditions decreased their proteasome-inhibitory activity, contributing to decreased cancer-preventive effects of tea consumption. Since (-)-EGCG is unstable under physiological conditions, we also developed the peracetate-protected or prodrug form of (-)-EGCG, Pro-EGCG (1), and shown that Pro-EGCG (1) increases the bioavailability, stability, and proteasome-inhibitory and anticancer activities of (-)-EGCG in human breast cancer cells and xenografts, suggesting its potential use for cancer prevention and treatment.
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Affiliation(s)
- Q P Dou
- The Prevention Program, Barbara Ann Karmanos Cancer Institute and Department of Pathology, School of Medicine, Wayne State University, 540.1 HWCRC, 4100 John R Rd, Detroit, Michigan 48201, USA.
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Chen D, Milacic V, Chen MS, Wan SB, Lam WH, Huo C, Landis-Piwowar KR, Cui QC, Wali A, Chan TH, Dou QP. Tea polyphenols, their biological effects and potential molecular targets. Histol Histopathol 2008; 23:487-96. [PMID: 18228206 DOI: 10.14670/hh-23.487] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tea is the most popular beverage in the world, second only to water. Tea contains an infusion of the leaves from the Camellia sinensis plant rich in polyphenolic compounds known as catechins, the most abundant of which is (-)-EGCG. Although tea has been consumed for centuries, it has only recently been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. The results of several investigations indicate that green tea consumption may be of modest benefit in reducing the plasma concentration of cholesterol and preventing atherosclerosis. Additionally, the cancer-preventive effects of green tea are widely supported by results from epidemiological, cell culture, animal and clinical studies. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols were shown to affect several biological pathways, including growth factor-mediated pathway, the mitogen-activated protein (MAP) kinase-dependent pathway, and ubiquitin/proteasome degradation pathways. Various animal studies have revealed that treatment with green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Recently, phase I and II clinical trials have been conducted to explore the anticancer effects of green tea in humans. A major challenge of cancer prevention is to integrate new molecular findings into clinical practice. Therefore, identification of more molecular targets and biomarkers for tea polyphenols is essential for improving the design of green tea trials and will greatly assist in a better understanding of the mechanisms underlying its anti-cancer activity.
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Affiliation(s)
- D Chen
- The Prevention Program, Barbara Ann Karmanos Cancer Institute and Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA
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Huo C, Ren XH, Liu BP, Yang YR, Rong SX. Fractal approach for modeling the morphology evolution of olefin polymerization with heterogeneous catalysts. J Appl Polym Sci 2003. [DOI: 10.1002/app.12597] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
Trabecular or cancellous bone is a major element in the structural design of the vertebrate skeleton, but has received little attention from the perspective of the biology of scale. In this study, we investigated scaling patterns in the discrete bony elements of cancellous bone. First, we constructed two theoretical models, representative of the two extremes of realistic patterns of trabecular size changes associated with body size changes. In one, constant trabecular size (CTS), increases in cancellous bone volume with size arise through the addition of new elements of constant size. In the other model, constant trabecular geometry (CTG), the size of trabeculae increases isometrically. These models produce fundamentally different patterns of surface area and volume scaling. We then compared the models with empirical observations of scaling of trabecular dimensions in mammals ranging in mass from 4 to 40x10(6)g. Trabecular size showed little dependence on body size, approaching one of our theoretical models (CTS). This result suggests that some elements of trabecular architecture may be driven by the requirements of maintaining adequate surface area for calcium homeostasis. Additionally, we found two key consequences of this strongly negative allometry. First, the connectivity among trabecular elements is qualitatively different for small versus large animals; trabeculae connect primarily to cortical bone in very small animals and primarily to other trabeculae in larger animals. Second, small animals have very few trabeculae and, as a consequence, we were able to identify particular elements with a consistent position across individuals and, for some elements, across species. Finally, in order to infer the possible influence of gross differences in mechanical loading on trabecular size, we sampled trabecular dimensions extensively within Chiroptera and compared their trabecular dimensions with those of non-volant mammals. We found no systematic differences in trabecular size or scaling patterns related to locomotor mode.
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Affiliation(s)
- S M Swartz
- Department of Ecology, Brown University, Providence, RI 02912, USA.
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