Our objective was to study the effects of three (30, 40, and 50 mg/kg) doses of Streptozotocin (STZ) on fasting plasma glucose level (FPG) and observe its effects at the cellular level in rat pancreas by electron microscopy. FPG was measured in rats before induction of diabetes and then on 3, 7, and 14 days after induction of diabetes with STZ. Keto diastix urine strips were used to check urine glucose and ketone bodies. Two weeks after the induction of diabetes, the rat pancreas was removed and fixed for light and electron microscopic studies. Three days after induction, the mean FPG level was 112 mg/dl in Group I (30 mg/kg STZ), 217 mg/dl in Group II (40 mg/kg STZ), and 376 mg/dl in Group III (50 mg/kg STZ). Histology was normal in Group I but revealed altered islet structure in Groups II and III. Ultrastructure revealed intact D cells in all three groups. The focal mitochondria and Golgi complex swelling found in A and B cells was occasional in Group I and frequent in Groups II and III. Swelling of other organelles and reduction in the size and number of granules was further observed in Group III. It is our conclusion that the 30-mg/kg body weight STZ produces mild changes while 50 mg/kg proves to be fatal. STZ at 40 mg/kg has a moderate effect on plasma glucose as well as on the islets of Langerhans at a cellular level.

Background:Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia. Plant extracts and their products are being used as an alternative system of medicine for the treatment of diabetes. Aloe vera has been traditionally used to treat several diseases and it exhibits antioxidant, anti-inflammatory, and wound-healing effects. Streptozotocin (STZ)-induced Wistar diabetic rats were used in this study to understand the potential protective effect of A. vera extract on the pancreatic islets.Objective:The aim of the present study was to evaluate the A. vera extract on improvement of insulin secretion and pancreatic β-cell function by morphometric analysis of pancreatic islets in STZ-induced diabetic Wistar rats.Materials and Methods:After acclimatization, male Wistar rats, maintained as per the Committee for the Purpose of Control and Supervision of Experiments on Animals guidelines, were randomly divided into four groups of six rats each. Fasting plasma glucose and insulin levels were assessed. The effect of A. vera extract in STZ-induced diabetic rats on the pancreatic islets by morphometric analysis was evaluated.Results:Oral administration of A. vera extract (300 mg/kg) daily to diabetic rats for 3 weeks showed restoration of blood glucose levels to normal levels with a concomitant increase in insulin levels upon feeding with A. vera extract in STZ-induced diabetic rats. Morphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with A. vera extract when compared to the untreated diabetic rats.Conclusion:A. vera extract exerts antidiabetic effects by improving insulin secretion and pancreatic β-cell function by restoring pancreatic islet mass in STZ-induced diabetic Wistar rats.SUMMARY Fasting plasma glucose (FPG) and insulin levels were restored to normal levels in diabetic rats treated with Aloe vera extractIslets of pancreas were qualitatively and quantitatively restored to normalcy leading to restoration of FPG and insulin levels of diabetic rats treated with Aloe vera extractMorphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with Aloe vera extract when compared to the untreated diabetic rats. Abbreviations Used: A. vera, FPG: Fasting plasma glucose, STZ: Streptozotocin, BW: Body weight

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The aim of this study was to assess recovery, cell death, and cell composition of post-thaw cultured human islets. Cryopreserved islets were provided by the Clinical Islet Transplant Program, Edmonton, Canada. Islets were processed using media prepared in accordance with Pre-Edmonton and Edmonton protocols. Cryopreserved islets were rapidly thawed and cultured for 24 h, 3 d, 5 d, and 7 d, following which they were processed for histology. Islet quantification, integrity, morphology and tissue turnover were studied via hematoxylin and eosin stained sections. Ultrastructure was studied by electron microscopy and endocrine cell composition by immunohistochemistry. Using the Pre-Edmonton protocol, islet recovery was 50.1% and islet survival was 50% at 24 h while for the Edmonton protocol, the islet recovery was 69.4% (p<0.001) and islet survival, 50% at ≈2.5 d. With an increasing culture duration although the physical integrity was retained there was an increasing loss of cohesivity both at light microscopic and at ultrastructure level regardless of the protocols used. Percentage islet survival and tissue turnover correlated negatively with culture duration in both protocols. The Edmonton protocol appears to preserve the islets better. However, culture duration adversely affects islet survival and quality, indicating the need for more optimal cryopreservation and culture techniques.

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Summary:The role of amifostine in the prevention of cyclophosphamide-induced hemorrhagic cystitis (HC) was evaluated in the rat model. Urinary bladders from control rats that received no drugs (group I) were compared with those from rats receiving cyclophosphamide alone at a dose of 150 mg/kg (group II), and two other groups receiving amifostine at 100 mg/kg (group III) and 200 mg/kg (group IV), 15 min prior to cyclophosphamide. Bladders were assessed macroscopically and histologically at 24 h and after 7 days. All the animals that received cyclophosphamide alone developed severe HC. On the basis of the scores of macroscopic and histologic changes, animals that received amifostine showed excellent uroprotection. Only 2/6 rats in group III and 1/6 rats in group IV developed mild HC at 24 h. None of the rats in either of these groups showed any evidence of HC at 7 days. It is concluded that amifostine protects the urothelium against cyclophosphamide-induced HC. Keywords: amifostine; cyclophosphamide; hemorrhagic cystitis; prevention Hemorrhagic cystitis (HC) is a potentially life-threatening sequel of therapy with oxazaphosphorine agents (cyclophosphamide, ifosfamide). It tends to occur most frequently as a consequence of using high-dose cyclophosphamide as conditioning therapy for BMT. It has been noted in 40-50% of these patients and contributes to mortality in 2-4%. 1,2 The uro-toxicity of these drugs is related to contact of the lining epithelium with the renally excreted 4-hydroxy metabolites, particularly acrolein. Other factors including viral infections, radiation and drugs such as busulfan may also cause HC in patients undergoing BMT. 2 Since there is no effective treatment for this condition, the emphasis has been on prevention. The most widely employed method for prevention is the combination of 2-mercaptoethane sodium sulfonate (MESNA) and hydration. 3 This thiol molecule has been shown to bind acrolein and reduce its toxicity. In spite of this, up to 18% of patients can develop severe manifestations (grade III to

The present study is aimed at determining some haematological and biochemical parameters in the wild Indian bonnet monkeys as also the microscopic and ultrastructural characteristics of their pancreatic islets. Adult wild Indian bonnet monkeys (Macaca radiata radiata) of both sexes weighing between 2.5 and 4 kg were used in these experiments. Their platelet, reticulocyte and total leukocyte counts and the blood concentrations of hemoglobin and plasma proteins and the serum concentrations of aspartate amino transferase, alanine amino transferase and calcium are similar to the values reported for M. mulatta. Plasma glucose is lower when compared with reported values of M. mulatta and M. fascicularis. Insulin levels are comparable with those of M. mulatta and M. nigra. Histology of islets is similar to that of humans. Ovoid cell collections of islet cells are scattered throughout the pancreas. Ultrastructure of A, B and D cells is similar to humans. These findings suggest that this relatively underutilized macaques may be a suitable model for biomedical research.

Transplantation of pancreatic islets represents a promising way of curing type I diabetes (insulin-dependent diabetes mellitus). Culture enables the survival of endocrine tissue awaiting islet transplantation and reduces islet immunogenicity prior to xenografting. In this study, attempts were made to preserve the monkey islets in culture for 7 days and to study the ultrastructure by electron microscopy. The islets were isolated from monkey pancreas by the collagenase digestion method and were separated from acinar cells by dextran density gradient centrifugation. These islets were preserved in a humidified atmosphere of 5% carbon dioxide and 95% air for 7 days. The culture medium used was CMRL-1066. After 7 days of culture the islets were processed for light and electron microscopic studies, which revealed that the cultured islets were intact and maintained their structural integrity. Semi-thin sections of the cultured islets showed morphology with occasional structural alterations at the periphery. Dithizone staining of the cultured islets showed crimson red colour, proving that the islets were pure and without any exocrine contamination. Electron microscopy showed that the cultured islets had well-preserved alpha-, beta- and delta-cells. Different cell types of the monkey pancreatic islets were identified by the presence of their characteristic secretory granules. The ultrastructural characteristics present in hormone-synthesizing cells, i.e. rough-endoplasmic reticulum, Golgi apparatus, mitochondria and secretory granules, were observed as in native islets.