title: Effect of excessive methionine on the development of the cranial growth plate in newborn rats.
abstract: OBJECTIVE
  Methionine is an essential amino acid and pivotal for normal growth and development. However, previous animal studies have shown that excessive maternal intake of methionine causes growth restrictions, organ damages, and abnormal growth of the mandible in newborn animals. However, the effect of excessive methionine on the development of the cranial growth plate is unknown. This study investigated histological alterations of the cranial growth plate induced by high methionine administration in newborn rats.
  
  
  METHODS
  Twenty pregnant dams were divided into a control and an experimental group. The controls received a diet for rats and the experimental group was fed from the 18th gestational day with a special manufactured high methionine diet for rats. The high methionine diet was maintained until the end of the lactation phase (day 20). The offspring of both groups were killed at day 10 or 20 postnatally and their spheno-occipital synchondroses were collected for histological analysis.
  
  
  RESULTS
  The weight of the high-dose methionine treated experimental group was considerably reduced in comparison to the control group at day 10 and 20 postnatally. The cartilaginous area of the growth plate and the height of the proliferative zone were markedly reduced at postnatal day 10 in the experimental group.
  
  
  CONCLUSIONS
  In summary, the diet-induced hypermethioninemia in rat dams resulted in growth retardations and histomorphological changes of the spheno-occipital synchondrosis, an important craniofacial growth centre in newborns. This finding may elucidate facial dysmorphoses reported in patients suffering from hypermethioninemia.
authors.affiliation: University Medical Centre of Regensburg, Dental School, Department of Orthodontics, Franz-Josef-Strauss-Allee 11, Regensburg, Germany. piero.roemer@gmx.de
authors.forename: Piero
authors.initials: P
authors.lastname: Römer
authors.forename: Jens
authors.initials: J
authors.lastname: Weingärtner
authors.forename: Benjamin
authors.initials: B
authors.lastname: Desaga
authors.forename: Dietmar
authors.initials: D
authors.lastname: Kubein-Meesenburg
authors.forename: Claudia
authors.initials: C
authors.lastname: Reicheneder
authors.forename: Peter
authors.initials: P
authors.lastname: Proff
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001835:Body Weight / Q000187:drug effects; D001846:Bone Development / Q000187:drug effects; D001854:Bone Marrow Cells / Q000187:drug effects / Q000473:pathology; D002113:Calcification, Physiologic / Q000187:drug effects; D002356:Cartilage / Q000187:drug effects / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D019902:Chondrocytes / Q000187:drug effects / Q000473:pathology; D003393:Cranial Sutures / Q000187:drug effects* / Q000254:growth & development / Q000473:pathology; D005260:Female; D051457:Hyaline Cartilage / Q000187:drug effects / Q000473:pathology; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008715:Methionine / Q000009:adverse effects*; D009777:Occipital Bone / Q000187:drug effects / Q000254:growth & development; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011897:Random Allocation; D051381:Rats; D011917:Rats, Inbred Lew; D013100:Sphenoid Bone / Q000187:drug effects / Q000254:growth & development / Q000473:pathology; D013997:Time Factors
chemical_list: D008715:Methionine