1. Adaptive changes of maternal bone and intestine during lactation Asst. Prof. Kannikar Wongdee, Ph.D. Office of Academic Management, Faculty of Allied Health Sciences, Burapha University Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University E-mail: kannikar@buu.ac.th OHEC congress at Ambassador City Jomtien, Chonburi September 14, 2012

2. Bone Protect internal organs Site for muscle attachment Hematopoiesis Locomotion Dkimages.com, 2008; Anatowiki.com, 2008; Fitsugar.com, 2008; Wikimedia.org, 2008 99% of calcium is stored in bone.

3. Bone mass throughout life Not only post-menopausal period, pregnancy and lactation also induce massive bone loss. Bowman and Miller, J Musculoskel Neuron Interact, 2001; Charoenphandhu et al. Trends Endocrinol Metab, 2010 Picture: www.health.com; www.5election.com

4. Maternal calcium metabolism  Maternal calcium loss  Fetal transfer during pregnancy (third trimester)  Milk production (requires more calcium)  Calcium supply during lactation  Bone — bone resorption  Diet — intestinal calcium absorption Charoenphandhu et al., Trends Endocrinol Metab, 2010 Charoenphandhu et al. Trends Endocinol Metab, 2010

5. Adaptive changes of maternal intestine and bone Technical approach  Histomorphometry: bone histomorphometry, micro-CT  Cell biology and molecular biology techniques: PCR, immunohistochemistry Technical approach  Histomorphometry: bone histomorphometry, micro-CT  Cell biology and molecular biology techniques: PCR, immunohistochemistry Picture:www.albany.edu; www.boripat.ac.th

6. Maternal villous hypertrophy during lactation Wongdee K, Teerapornpuntakit J, Siangpro C, Chaipai S, Charoenphandhu N. Duodenal villous hypertrophy and upregulation of claudin-15 protein expression in lactating rats. Journal of Molecular Histology 2012 (in press). Picture: www.humpath.com Wongdee et al., J Mol Histol, 2012

7. Maternal bone loss during lactation Suntornsaratoon et al., Am J Physiol Endocrinol Metab, 2010  Human — up to 10% of skeletal mass  Lactation-induced osteoporosis (Ofluoglu and Ofluoglu, 2008)  Rodent (6–8 pups) — up to 30% of skeletal mass  Partly under the regulation of PRL Osteoclast surfaceEroded surface P = pregnancy; L = lactation; PW = postweaning Picture: www.health.com

8. Roles of PRL on maternal calcium metabolism Charoenphandhu N, Wongdee K, Krishnamra N. Is prolactin the cardinal calciotropic maternal hormone? Trends in Endocrinology & Metabolism 2010;21(7):395 ‒ 401.

9. Endochondral bone changes during lactation  Lactation-induced elongation of the long bone.  PRL-induced decreases in total growth plate height. Suntornsaratoon et al. Histochem Cell Biol, 2010 Wongdee et al. J Physiol Sci, 2012 Bone length Growth plate height

10. Perspective plan Fibroblast growth factor 23 (FGF23), bone-derived phosphate-regulating hormone Existence of FGF receptors in the intestinal villi. FGF23 compromised the 1,25(OH) 2 D 3 -induced intestinal calcium absorption. Khuituan et al. Am J Physiol Endocrinol Metab, 2012 Role of FGF23 in bone and intestine during pregnancy and lactation

11. Acknowledgements Assoc. Prof. Narattaphol Charoenphandhu, M.D., Ph.D.MU Prof. Nateetip Krishnamra, Ph.D.MU Chitchamai Siangpro, B.Sc. BUU Sunitra Chaipai, B.Sc. BUU Panan Suntornsaratoon, M.Sc.MU Natchayaporn Thonapan, B.ScMU Jarinthorn Teerapornpuntakit, M.Sc.MU Research grants Office of the Higher Education Commission Faculty of Allied Health Sciences, Burapha University Thailand Research Fund (TRF) NSTDA