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. DESIGN: 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.
Subject(s)
Cranial Sutures/drug effects , Methionine/adverse effects , Prenatal Exposure Delayed Effects , Animals , Animals, Newborn , Body Weight/drug effects , Bone Development/drug effects , Bone Marrow Cells/drug effects , Bone Marrow Cells/pathology , Calcification, Physiologic/drug effects , Cartilage/drug effects , Cartilage/pathology , Cell Proliferation/drug effects , Chondrocytes/drug effects , Chondrocytes/pathology , Cranial Sutures/growth & development , Cranial Sutures/pathology , Female , Hyaline Cartilage/drug effects , Hyaline Cartilage/pathology , Image Processing, Computer-Assisted/methods , Male , Occipital Bone/drug effects , Occipital Bone/growth & development , Pregnancy , Random Allocation , Rats , Rats, Inbred Lew , Sphenoid Bone/drug effects , Sphenoid Bone/growth & development , Sphenoid Bone/pathology , Time FactorsABSTRACT
This study was designed to investigate the effect of strontium on human PDL cells in vitro. Strontium is used to treat osteoporosis because of its bone formation promoting effect on osteoblast cells. This investigation presents evidence that strontium promotes PDL cell proliferation. Simultaneously, strontium suppresses the expression of the inflammation-promoting cytokine IL-6. The observed effect of strontium on PDL cells supports its use it in guided dental tissue regeneration.
