Diabetic animal models

NORMAL AND DIABETIC ANIMAL MODELS COMPATIBLE WITH THE WINDOW CHAMBER-BIOSENSOR SYSTEM... 

This chapter provides a synopsis of the salient host tissue responses that relate to implanted sensor performance and describes in detail the development and current adaptation of the window chamber-biosensor method to address host tissue factors. The use of normoglycemic and diabetic animal models, specifically the Syrian hamster and Fat Sand Rat, to study the role of the microvasculature on sensor function is described. Limitations of the window chamber-biosensor method are also outlined. Finally, some important and useful features of standard brightfield, fluorescence, confocal, and multiphoton imaging as they apply to the window chamber are noted. 

Mathe D. Dyslipidemia and diabetes animal models. Diab Metab 1995 2 106-11. 

Studies using experimental diabetic animal models have indicated that xenobiotic-induced hepatotoxicity is modulated in diabetes. Hepatotoxicity of several structurally and mechanistically diverse chemicals, such as chloroform, thioacetamide, menadione, nitro-soamines, bromobenzene, and CCI4, is significantly increased in type 1 diabetic rats. It was reported that thioacetamide-induced hepatotoxicity was potentiated in alloxan- or streptozotocin-diabetic rats. Recent studies have confirmed the potentiation of thioacetamide hepatotoxicity in streptozotocin-diabetic rats. Several studies have shown that hepatotoxicity of CCI4 is potentiated in alloxan- or streptozotocin-induced type 1 diabetic rats. 

The antidiabetic effects of chitosan and its derivatives were reported in diabetic animal models, type 1 and type 2. A number of studies have been reported in the literature. 

Chitosan and its derivative exhibited the great antihyperglycemic, antihyperlipidemic, and anti-hypocholesterolemic activities in type 1 and type 2 diabetic animal models. Moreover, chitin, chitosan, and their derivatives exhibited cholesterol-lowering activity in animal and clinical studies. Therefore, chitin, chitosan, and their derivatives can be promising candidates as potential material for protecting diabetes mellitus and lowering the cholesterol absorption. 

Mukhopadhyay P, Sarkar K, Chakraborty M, Bhattacharya S, Mishra R, Kundu PP. Oral insulin delivery by self-assembled chitosan nanoparticles in vitro and in vivo studies in diabetic animal model. Mater Sci Eng C. 2012 33(l) 376-82. 

Although few in number, some studies on ascorbic acid supplementation in diabetic individuals and in diabetic animal models have been reported. In man, ascorbic acid supplementation has been shown to increase cutaneous capillary strength, but to have no effect on retinopathy, until supplementation ceased, when some increases in retinal hemorrhage were observed (Cox et al., 1975). Ascorbic acid supplementation appears to increase plasma ascorbic acid concentration as well as dehydrdoascorbic acid concentration (Sinclair et al., 1991). Correction of ascorbic acid levels is only transient once supplementation is halted ascorbic acid levels return to the presupplementation level (Som et al., 1981 Sinclair et al., 1991). Thus, ascorbic acid supplementation has shown no beneficial effect and on one occasion has proved harmful on withdrawal. It is possible that a sudden reduction in ascorbic acid intake may lead to a dramatic fall in plasma and tissue levels with subsequent adverse effects (Halliwell, 1994). 

In recent researches, stem cells have brought to new hope. Bone marrow with two major stem cells (hematopoietic and mesenchymal stem cells), the adult bone-marrow derived stem cells can regenerate the fl cell in diabetes animal models. These results lead to a new approach in diabetes treatment, especially type 1 diabetes. 

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