Banca de QUALIFICAÇÃO: RAUL HERNANDES BORTOLIN

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: RAUL HERNANDES BORTOLIN
DATA: 07/10/2014
HORA: 14:00
LOCAL: Sala de aula 02 -PPGCSA
TÍTULO:

Protection against diabetes-induced bone loss by zinc supplementation

PALAVRAS-CHAVES:

T1DM animal model; Bone loss; Zn supplementation; Biomechanical parameters, Molecular biomarkers

PÁGINAS: 30
GRANDE ÁREA: Ciências da Saúde
ÁREA: Farmácia
RESUMO:

Background: The relationship between skeletal abnormalities and diabetic bone disease is well established and recognized to be a complex pathogenesis. Zinc (Zn) supplementation is a preventive agent against bone loss acting on stimulation of bone formation and inhibition of bone resorption, however, the Zn effect on T1DM-induced bone loss in a chronic condition is not well established.

Methodology and Principal Findings: Male Wistar rats were distributed in three groups (five rats per group): Control, Diabetic (T1DM, STZ-induced, i.v) and Diabetic supplemented with 500 mg/day of Zn during 90 days (T1DMS). Biochemical, tibia biomechanical, histomorphometric parameters and femur mRNA expression were evaluated. It was observed a bone loss in T1DM through alteration on histomorphometric parameters such as decrease of Tb.Wi, B.Ar and increase of Tb.Sp, a decrease on biomechanical parameters (i.e. Maximum Load, Stiffness, Ultimate Strain and Young´s modulus), as well as a low collagen content compared to Control. Molecular parameters, showed in response to hyperglycemic chronic condition (T1DM), an up regulation of the OPG, OC, COL1A and MMP9 compared to Control. This finds characterize a low bone strength and flexibility associated to T1DM. Interestingly, Zn showed an important protective effect against bone loss in a chronic glucose exposure. T1DMS showed similar values in T1DMS group to histomorphometric and biomechanical parameter compared with Control. Zn also, has a protective effect on maintenance on gene regulation, showing regulation near to basal values found in a Control. Moreover, Zn showed an important anabolic effect, which was observed by up regulation on OC in association with high serum ALP activity, parameters related to osteoblastogenesis, characterizing an positive effect on bone formation and a possible interaction with bone metabolism control in a chronic hyperglycemic condition. Conclusions/Significance: Thus, these results support that Zn supplementation prevented bone loss associated to long term T1DM and represent a potential complementary therapy in patients with diabetes or other related chronic disease.

MEMBROS DA BANCA:
Presidente - 2323511 - ADRIANA AUGUSTO DE REZENDE
Externo ao Programa - 1510735 - DANILO ALVES PINTO NAGEM
Externo ao Programa - 2477216 - NAISANDRA BEZERRA DA SILVA