**1. Introduction**

224 Apoptosis and Medicine

54: 795-809.

327–338.

[79] Ota M, Tsuji M, Mochizuki Y, Inagaki M, Murayama M, Emori H, Sambe T, Oguchi K (2011) Ethanol-induced stress leads to apoptosis via endoplasmic reticulum stress in

[80] Halsted CH (2004) Nutrition and alcoholic liver disease. Semin. Liver Dis. 24: 289-304. [81] Ji C (2008) Dissection of endoplasmic reticulum stress signaling in alcoholic and non-

[82] Dara L, Ji C, Kaplowitz N (2011) The contribution of endoplasmic reticulum stress to

[83] Malhi H, Kaufman RJ (2011) Endoplasmic reticulum stress in liver disease. J. Hepatol.

[84] Ji C, Kaplowitz N, Lau MY, Kao E, Petrovic LM, Lee AS (2011) Liver-specific loss of glucose-regulated protein 78 perturbs the unfolded protein response andexacerbates a

[85] Boyce M, Bryant KF, Jousse C, Long K, Harding HP, Scheuner D, Kaufman RJ, Ma D, Coen DM, Ron D, Yuan J (2005) A selective inhibitor of elF2*a* dephosphorylation

[86] Malhi H, Gores GJ (2008) Cellular and molecular mechanisms of liver injury.

[87] Gores GJ (1999) Death receptors in liver biology and pathobiology. Hepatology 29: 1-4. [88] Akazawa Y, Gores GJ (2007) Death receptor-mediated liver injury. Semi. Liver Dis. 27:

[89] Sodeman T, Bronk SF, Roberts PJ, Miyoshi H, Gores GJ (2000) Bile salts mediate hepatocyte apoptosis by increasing cell surface trafficking of Fas. Am. J.

SK-Hep1 cells. Showa Univ. J. Med. Sci. 23: 23-35.

liver diseases. Hepatology 53: 1752-1763.

alcoholic liver injury. J. Gastroenterol. Hepatol. 23: S16-S24.

spectrum of liver diseases in mice. Hepatology 54: 229-239.

protects cells from ER stress. Science 307: 935-939.

Physiol.Gastrointest. Liver Physiol. 278: G992-G999.

Gastroenterology 134: 1641-1654.

For screening and detailed studying of antidiabetic medications, various genetic and nongenetic experimental models of diabetes mellitus were used (Islam S., Loots D.T. 2009). And though they are not absolutely equivalent to etiopathogenetic mechanisms of human pathological conditions, each of them represents itself as an integral tool for research into genetic, endocrine, metabolic, morphological changes of this disease (Sarvilina I.V., Maclakov Y.S. 2008).

The most commonly used diabetic experimental models are non-genetic models that use hydrophilic β-cell glucose analogues, such as alloxan, streptozotocin, chlorozotocin, cyproheptadine, etc. The common mechanism of action of these substance includes degradation of pancreatic islet β-cells by means of: 1) generation of oxygen free radicals that destroy the integrity of a cell, 2) alkylation of DNA and subsequent activation of poly-ADPribose-synthetase - reduction of NAD to β-cell, and 3) inhibition of active transport of calcium and calmodulin-activated protein kinase (Rees D.A., Alcolado J.C. 2005). In this type of experimental models of diabetes mellitus streptozotocin (an N-nitrosourea derivative of glucosamine) is most commonly used (McNeill J.H. 1999). Depending on cytotoxin dosage used in the experiment (45-70 mg/kg) and route of administration (i.p., i.v.), it is possible to model and simulate different states of carbohydrate metabolism based on a specific clinical type of diabetes mellitus (DM mixed (type 1-2) latent or «hidden» diabetes) (Srinivasan K. et al. 2007). Although diabetes mellitus usually has obvious clinical symptoms such as hyperglycemia, glucosuria, polyuria, polydipsia, severe weight loss, it is difficult to measure the contribution of each of the links to the pathogenesis of diabetes and to assess the extent of pancreatic islet β-cell damage and death. The toxic effect of alloxan and streptozotocin on cells in pancreatic islets manifests itself not only by necrosis but also by apoptosis of pancreatic islet β-cells (Daisy Mythili M., et al. 2004). The study of apoptotic mechanisms

© 2012 Smirnov et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. will enable us to identify specific targets for purposeful creation and development of antidiabetic medications.

Pancreatic Islet Beta-Cell Apoptosis in Experimental Diabetes Mellitus 227

Experimental immune-dependent diabetes simulation model was developed by giving a subcutaneous injection of 0.2 ml of complete Freund's adjuvant (CFA) (Grand Island Biological Company, USA). Subsequently, daily intravenous injections of streptozotocin (Sigma, USA) (20 mg/kg) were given to the animals for 5 days, resulting in the development of insulindependent diabetes (Ziegler B. 1990). Tissue samples were collected and submitted for routine

Streptozotocin-nicotinamide-induced diabetes model was developed by giving an injection of streptozotocin (Sigma, USA) (intraperitoneally - 65 mg/kg citrate buffer, pH = 4.5) with a preliminary (15 minutes prior to the procedure) administration of nicotinamide (intraperitoneally - 230 mg/kg prepared in 0.9 % solution of sodium chloride) (Islam S., et al. 2009). Tissue samples were collected and submitted for routine histopathological

Pancreatic tissue was divided into three segments including intestinal, gastric and splenic parts, and then they were fixed in 10% solution of neutral buffered formalin (pH 7.4) for 24 hours. 5-6-mm thick slices were obtained on rotary microtomes and were mounted on slides. Tissue sections were stained with hematoxylin and eosin using standard histological

For detection of α-and β- endocrine cells in the islets of Langerhans the primary antibodies against insulin and glucagon were used (Table 2). To study apoptosis, the primary antibodies to proteins, such as caspase 3, TRAIL (TNF-related apoptosis-inducing ligand),

**№ Antibody Clone Manufacturer** 1 Insulin Polyclonal DakoCytomation, Denmark

2 Glucagon Polyclonal Novocastra, UK 3 Caspase 3 JHM62 Novocastra, UK

4 TRAIL 27B12 Novocastra, UK 5 MDM2 1B10 Novocastra, UK

Ab-1 (Pab 240) MS-104-

9 NOS-3 RN5 Novocastra, UK

P0

**Table 2.** IHC Primary Antibodies

Ab-6 (INS04 + INS05) LabVision, UK 2D11-H5 Novocastra, UK

Rb-1197-P0 NeoMarkers, USA

124 Dako Cytomation, Denmark

NeoMarkers, USA

6 Bcl 2 sc-7382 Santa Cruz Biotechnology, USA

8 Bax Polyclonal BD Biosciences Pharmingen, USA

7 p53 Polyclonal Dako Cytomation, Denmark

10 NF-kB Polyclonal Diagnostic BioSystems, USA

histopathological investigation at 3, 7, 14 and 28 days of the experiment.

investigation at 3, 7, 14 and 28 days of the experiment.

MDM2, Bcl 2, p53, Bax, NF-kB, as well as eNOS were used.

stain techniques (Korzhevsky D.E. 2005).
