title: Altered ureteric branching morphogenesis and nephron endowment in offspring of diabetic and insulin-treated pregnancy.
abstract: There is strong evidence from human and animal models that exposure to maternal hyperglycemia during in utero development can detrimentally affect fetal kidney development. Notwithstanding this knowledge, the precise effects of diabetic pregnancy on the key processes of kidney development are unclear due to a paucity of studies and limitations in previously used methodologies. The purpose of the present study was to elucidate the effects of hyperglycemia on ureteric branching morphogenesis and nephrogenesis using unbiased techniques. Diabetes was induced in pregnant C57Bl/6J mice using multiple doses of streptozotocin (STZ) on embryonic days (E) 6.5-8.5. Branching morphogenesis was quantified ex vivo using Optical Projection Tomography, and nephrons were counted using unbiased stereology. Maternal hyperglycemia was recognised from E12.5. At E14.5, offspring of diabetic mice demonstrated fetal growth restriction and a marked deficit in ureteric tip number (control 283.7 ± 23.3 vs. STZ 153.2 ± 24.6, mean ± SEM, p<0.01) and ureteric tree length (control 33.1 ± 2.6 mm vs. STZ 17.6 ± 2.7 mm, p = 0.001) vs. controls. At E18.5, fetal growth restriction was still present in offspring of STZ dams and a deficit in nephron endowment was observed (control 1246.2 ± 64.9 vs. STZ 822.4 ± 74.0, p<0.001). Kidney malformations in the form of duplex ureter and hydroureter were a common observation (26%) in embryos of diabetic pregnancy compared with controls (0%). Maternal insulin treatment from E13.5 normalised maternal glycaemia but did not normalise fetal weight nor prevent the nephron deficit. The detrimental effect of hyperglycemia on ureteric branching morphogenesis and, in turn, nephron endowment in the growth-restricted fetus highlights the importance of glycemic control in early gestation and during the initial stages of renal development.
authors.affiliation: Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.
authors.forename: Stacey N
authors.initials: SN
authors.lastname: Hokke
authors.forename: James A
authors.initials: JA
authors.lastname: Armitage
authors.forename: Victor G
authors.initials: VG
authors.lastname: Puelles
authors.forename: Kieran M
authors.initials: KM
authors.lastname: Short
authors.forename: Lynelle
authors.initials: L
authors.lastname: Jones
authors.forename: Ian M
authors.initials: IM
authors.lastname: Smyth
authors.forename: John F
authors.initials: JF
authors.lastname: Bertram
authors.forename: Luise A
authors.initials: LA
authors.lastname: Cullen-McEwen
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental; D005260:Female; D047109:Fetal Development / Q000187:drug effects; D006801:Humans; D006943:Hyperglycemia / Q000139:chemically induced / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism / Q000494:pharmacology; D051379:Mice; D009024:Morphogenesis / Q000187:drug effects; D009399:Nephrons / Q000187:drug effects / Q000196:embryology*; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000139:chemically induced / Q000378:metabolism*; D011297:Prenatal Exposure Delayed Effects; D013311:Streptozocin / Q000009:adverse effects; D014513:Ureter / Q000187:drug effects / Q000196:embryology*; D014551:Urinary Tract / Q000002:abnormalities / Q000196:embryology
chemical_list: D001786:Blood Glucose; D007328:Insulin; D013311:Streptozocin