Reduction of podocytes number in late diabetic alloxan nephropathy: prevention by glycemic control.
OBJECTIVE
To determine podocyte number and GBM thickness in diabetic rats either under glycemic control or without glycemic control at 6 and 12 months after diabetes induction.


METHODS
100 Wistar rats weighing 200-300g were divided into 6 groups: Normal group (N6 and N12- 25 rats); Diabetic group (D6 and D12- 25 rats), diabetic treated group ( DT 6 and DT 12- 25 rats) on insulin 1,8- 3,0 IU/Kg associated with acarbose (50 mg to 100g of food) daily mixed in chow. Alloxan was injected intravenously in a dose of 42 mg/Kg of weight. Body weight, water intake, 24-h diuresis, glycemia and glucosuria were determined before induction, 7 and 14 days after induction and monthly thereafter. Treatment started at day 14. Three groups were sacrificed at 6 months (N6,D6, DT6) and 3 groups at 12 months (N12, D12, DT12) with the renal tissue being prepared for electron microscopy.


RESULTS
Glycemia in DT6" and in DT12 was significantly different from that in D6 and D12 rats and similar to that in N6 and N12 animals. The number of podocytes in DT6 was not different from that in N6 and D6 (median = 11); the number of podocytes in DT12 (median = 11) differed from that in D12 (median = 8), but not from that in N12 (median = 11). GBM thickness in D6 (0.18 micrometers) was lower than in D12 (0.29 micrometers); while in DT6 (0.16 micrometers) it was lower than in D6 (0.18 micrometers). In DT12 (0.26 micrometers), it was lower than in D12 (0.29 micrometers).


CONCLUSIONS
The control of hyperglycemia prevented GBM thickening in early and late (12 mo) alloxan diabetic nephropathy and podocyte number reduction.
Macedo
Célia Sperandéo
CS
Experimental Laboratory-Technique of Surgery, Department of Surgery and Orthopedics, School of Medicine, São Paulo State University, Botucatu, SP, Brazil.
Lerco
Mauro Masson
MM
Capelletti
Sônia Maria
SM
Silva
Reinaldo José
RJ
Pinheiro
Daniela de Oliveira
Dde O
Spadella
César Tadeu
CT
D020909:Acarbose / Q000008:administration & dosage; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D003928:Diabetic Nephropathies / Q000209:etiology / Q000473:pathology* / Q000517:prevention & control; D004195:Disease Models, Animal; D005260:Female; D050533:Glomerular Basement Membrane / Q000187:drug effects / Q000648:ultrastructure*; D007004:Hypoglycemic Agents / Q000008:administration & dosage; D007328:Insulin / Q000008:administration & dosage; D008297:Male; D050199:Podocytes / Q000187:drug effects* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D020909:Acarbose