Insulin-treated Diabetic Group Research Articles

Abstract TMP117: Exposure to Single or Recurrent Hypoglycemia Increases Stroke Risk in Insulin-Treated Female Diabetic Rats

Stroke is a serious complication of diabetes. Intensive treatment of diabetes increases the risk of recurrent hypoglycemia (RH). Hypoglycemia exposure causes prothrombotic effects. Earlier, we demonstrated that exposure to single hypoglycemia (SH), 5-day RH (once every day), and twice-a-week RH for 6 weeks increases stroke risk in male insulin-treated diabetic (ITD) rats. In the present study, we determined the effect of SH and RH on stroke risk/thrombosis in female rats. Streptozotocin diabetic female rats were treated for hyperglycemia using insulin pellets (Figure A). Rats were randomly assigned to either hyperinsulinemic euglycemia (ITD+RH+Glucose, control) or hyperinsulinemic hypoglycemia (ITD+RH) groups (3 h duration) (Figure B). Separate groups tested the effect of SH, RH for 5 days, or RH for 6 weeks. Based on the results of the male studies, stroke risk after SH, 5-day RH, and 6-week RH were assessed on days 1, 7, and 3 post-last hypoglycemia, respectively. Groups were balanced (confirmed by Chi square test) in terms of the proportion of animals at different stages of the estrous cycle. To assess the risk of stroke, the carotid artery and jugular vein were linked with a shunt containing a suture, and the weight of the clot accumulated on the suture following 15 min of blood flow was quantified as a measure of stroke risk/thrombosis. The clot weight in the SH-exposed ITD group was significantly higher by 47% (22±3 mg, n=9, p<0.05) when compared to its respective control (15±1 mg, n=8). The clot weight determined 7 days after the 5-day ITD+RH group (18±1 mg, n=7) was significantly (p<0.05) higher than its control group (15±1 mg, n=9). The clot weight in the 6-week ITD+RH group was significantly higher by 47% (20±2 mg, n=9, p<0.01) when compared to its control (14±1 mg, n=7) (Figure C). Our results show that similar to male rats, SH and RH increase stroke risk in female ITD rats. We are currently evaluating the underlying mechanisms. Acknowledgment: NIH (NS122808).

Trichosanthin alleviates streptozotocin-induced type 1 diabetes mellitus in mice by regulating the balance between bone marrow-derived IL6+ and IL10+ MDSCs

Myeloid-derived suppressor cells (MDSCs) occupy a pivotal role in the intricate pathogenesis of the autoimmune disorder, Type 1 diabetes mellitus (T1DM). Since our previous work demonstrated that trichosanthin (TCS), an active compound of Chinese herb medicine Tian Hua Fen, regulated immune response, we aimed to clarify the efficacy and molecular mechanism of TCS in the treatment of T1DM. To this end, T1DM mouse model was established by streptozotocin (STZ) induction. The mice were randomly divided into normal control group (Ctl), T1DM group (STZ), TCS treated diabetic group (STZ + TCS) and insulin-treated diabetic group (STZ + insulin). Our comprehensive evaluation encompassed variables such as blood glucose, glycosylated hemoglobin, body weight, pertinent biochemical markers, pancreatic histopathology, and the distribution of immune cell populations. Furthermore, we meticulously isolated MDSCs from the bone marrow of T1DM mice, probing into the expressions of genes pertaining to the advanced glycation end product receptor (RAGE)/NF-κB signaling pathway through RT-qPCR. Evidently, TCS exhibited a substantial capacity to effectively counteract the T1DM-induced elevation in random blood glucose, glycosylated hemoglobin, and IL-6 levels in plasma. Pathological scrutiny underscored the ability of TCS to mitigate the damage incurred by islets. Intriguingly, TCS interventions engendered a reduction in the proportion of MDSCs within the bone marrow, particularly within the IL-6+ MDSC subset. In contrast, IL-10+ MDSCs exhibited an elevation following TCS treatment. Moreover, we observed a significant down-regulation of relative mRNA of pro-inflammatory genes, including arginase 1 (Arg1), inducible nitric oxide synthase (iNOS), RAGE and NF-κB, within MDSCs due to the influence of TCS. It decreases total MDSCs and regulates the balance between IL-6+ and IL-10+ MDSCs thus alleviating the symptoms of T1DM. TCS also down-regulates the RAGE/NF-κB signaling pathway, making it a promising alternative therapeutic treatment for T1DM. Collectively, our study offered novel insights into the underlying mechanism by which TCS serves as a promising therapeutic intervention for T1DM.

Maternal diabetes decreases the expression of GABAAα1, GABAB1, and mGlu2 receptors in the visual cortex of male rat neonates

AimsThis study examines the impact of maternal diabetes on the expression of GABAB1, GABAAα1, and mGlu2 receptors in the primary visual cortex layers of male rat newborns.Main Methods: In diabetic group (Dia), diabetes was induced in adult female rats using an intraperitoneal dose of Streptozotocin (STZ) 65 (mg/kg). Diabetes was managed by daily subcutaneous injection of NPH insulin in insulin-treated diabetic group (Ins). Control group (Con) received normal saline intraperitoneally rather than STZ. Male offspring born to each group of female rats were euthanized via CO2 inhalation at P0, P7, and P14 days after delivery and the expression of GABAB1, GABAAα1, and mGlu2 receptors in their primary visual cortex was determined using immunohistochemistry (IHC).Key Findings: The expression of GABAB1, GABAAα1, and mGlu2 receptors increased gradually with age in the male offspring born to Con group while the highest expression was detected in layer IV of the primary visual cortex. In Dia group newborns, the expression of these receptors was significantly reduced in all layers of the primary visual cortex at every three days. Insulin treatment in diabetic mothers restored the expression of these receptors to normal levels in their newborns. SignificanceThe study indicates that diabetes reduces the expression of GABAB1, GABAAα1, and mGlu2 receptors in the primary visual cortex of male offspring born to diabetic rats at P0, P7, and P14. However, insulin treatment can counteract these effects.

Continuous Interstitial Glucose Measurement for Flap Venous Occlusion Monitoring in a Diabetic Model.

Glucose has been used in the monitoring of transplanted flaps. However, few studies have focused on the effect of diabetes on the decrease in flap glucose levels. The purpose of this study was to evaluate the application of continuous interstitial glucose monitoring to detect flap venous occlusion in a diabetic rat model. The flap interstitial glucose level was measured by transcutaneous sensors in the bilateral vertical rectus abdominis myocutaneous flaps of each rat. interstitial glucose values in the bilateral flaps were recorded every 5 minutes after the venous occlusion of 1 flap. Forty-one rats were divided into the control group (n = 13), diabetic group (n = 15, established by the intraperitoneal injection of streptozotocin), and insulin-treated diabetic group (n = 13, systemic glucose well controlled by insulin before surgery). Results indicated that flap interstitial glucose decreased to the lowest level in all flaps with venous occlusion. The time from venous occlusionto the lowest interstitial glucose level was significantlylongerinthe diabetic group than the control group (120.8 ± 5.7 minutes versus 56.5 ± 6.7 min-minutes, P < 0.001), but was similar in the insulin-treated diabetic and control groups (56.5 ± 6.7 minutes versus 56.0 ± 6.6 minutes, P = 0.876). The change in interstitial glucose in both the diabetic and insulin-treated diabetic groups began with a plateau period or a slow decline before decreasing for 49.0 ± 6.4 minutes and 24.4 ± 4.3 min-minutes, respectively. in a diabetic rat model, impaired glucose metabolism prolongs the required monitoring time and dulls the reaction of flap interstitial glucose to venous congestion. Insulin restores the prolonged monitoring time, but not the reaction of flap interstitial glucose. Therefore, care is needed during application of the technique in diabetic patients.

Beneficial effects of MgSO4 on TFAM, UPC3 and FNDC5 mRNA expressions in skeletal muscle of type 2 diabetic rats: a possible mechanism to improve insulin resistance

Hypomagnesemia has been associated with development of type 2 diabetesmellitus (T2DM) and its complications. Irisin has beneficial effects on glucose uptake and improves hepatic glucose and lipid metabolism. In this study, we aimed to evaluate the effects of long-term treatment of MgSO4 and insulin on insulin resistance, dyslipidemia, serum and hepatic irisin levels, skeletal muscle gene expression of fibronectin type III domain-containing protein 5 (FNDC5), mitochondrial transcription factor A (TFAM) and mitochondrial uncoupling protein 3 (UCP3) in T2DM rats. Twenty-four rats were divided into four groups: Control group, diabetic control (DC) using a high-fat diet + streptozotocin, insulin-treated diabetic group (DC + Ins), MgSO4-treated diabetic group (DC + Mg). At the end of therapies, serum concentrations of FBG, TG, insulin, Ox-LDL, along with serum and hepatic irisin levels were measured. FNDC5, TFAM, and UCP3 mRNA expressions were measured in the skeletal muscle by Real-time PCR. In comparison with DC group, MgSO4 therapy resulted in decreased FBG, TG, Ox-LDL, improved serum insulin and irisin levels, and increased mRNA expressions of FNDC5, UCP3 and TFAM. Insulin therapy significantly decreased FBG, Ox-LDL, FNDC5 and serum irisin levels compared with the control group. While, insulin therapy markedly increased TFAM and UCP3 compared with the DC group. In conclusion, MgSO4 can improve insulin resistance and hyperlipidemia partly through decreasing Ox-LDL, increasing serum irisin levels as well as increasing FNDC5, TFAM, and UCP3 mRNA expressions in T2DM rats. These findings can be considered in the management of diabetes treatment.

Troxerutin affects nephropathy signaling events in the kidney of type-1 diabetic male rats.

Objective:Nephropathy is known to be the leading cause of kidney failure in diabetic patients. Troxerutin, as a flavonoid component, could provide a novel protective strategy in the prevention of diabetic nephropathy. A large number of reports on the salutary effects of troxerutin inspired us to investigate its effect on the nephropathy signaling events (i.e., expression of TGF-β, miRNA192, and SIP1) in type-1 induced diabetic rats.Materials and Methods:50 male Wistar rats were divided into 5 groups including control group, sham group treated with troxerutin for 4 weeks, diabetic group induced by streptozotocin (STZ) injection, DI group including insulin-treated diabetic animals and DT group treated with troxerutin. Ultimately, rat kidneys were extracted, and the level of miR-192 (using qPCR), transforming growth factor-beta (TGF-β), and smad interacting protein 1 (SIP1) using an ELISA kit, was measured.Results:The level of TGF-β and miRNA192 significantly increased in the diabetic group. However, their expression levels decreased following the administration of troxerutin and insulin (p<0.05) compared to control group. SIP1 was down-regulated in the diabetic group, whereas a spike in the expression levels was observed after troxerutin administration compared to control and troxerutin groups (p<0.05). However, no significant difference was found in the effects of insulin and troxerutin on the level of miR-192, SIP1, and TGF- β. Conclusion:According to the previous literatures, during the progression of nephropathy, TGF-β represses SIP1 (the repression region in the collagen gene) by increasing the expression of miR-192. Ultimately, in this study, diabetes led to up-regulation of TGF-β while troxerutin proved to have a protective effect on the kidney by increasing SIP and lowering miR-192 levels.

Catecholamines production by kidney tissue and mesangial cell culture is differentially modulated by diabetes.

Introduction:According to the International Diabetes Federation, the number of people with diabetes mellitus may reach 700 million in 2045. Catecholamines are involved in the regulation of several kidney functions. This study investigates the effects of hyperglycemia on catecholamines' metabolism in kidney tissue from control, diabetic, and insulin-treated diabetic rats, both in vivo and in vitro.Methods:Male Wistar-Hannover rats were randomized into: control, diabetic, and insulin-treated diabetic groups. Diabetes was induced by a single injection of streptozotocin, and diabetic treated group also received insulin. After 60 days, blood and kidney tissue from all groups were collected for catecholamines' quantification and mesangial cells culture.Results:diabetic rats had lower body weight, hyperglycemia, and increase water intake and diuresis. Additionally, diabetes promoted a sharp decrease in creatinine clearance compared to control group. Regarding the whole kidney extracts, both diabetic groups (treated and non-treated) had significant reduction in norepinephrine concentration. In mesangial cell culture, catecholamines' concentration were lower in the culture medium than in the intracellular compartment for all groups. Norepinephrine, epinephrine, and dopamine medium levels were increased in the diabetic group.Conclusion:The major finding of the present study was that 8 weeks of diabetes induction altered the kidney catecholaminergic system in a very specific manner, once the production of catecholamines in the excised kidney tissue from diabetic rats was differentially modulated as compared with the production and secretion by cultured mesangial cells.

Serum Bilirubin Levels Can be Used as a Potential Biomarker in the Progression of Diabetic Nephropathy in Rats

AbstractBackground: Diabetes mellitus is a widespread syndrome and a major cause of morbidity and mortality all over the world. Diabetic nephropathy is a progressive and irreversible renal affection that may end by renal failure in sever conditions. Bilirubin is the end product of heme catabolism. It has been recognized as a strong antioxidant. Many studies relate bilirubin to diabetes.Aim of Study: The present investigation aimed to study the changes in serum billirubin level in diabetic nephropathy and to know whether there is a correlation between its level and the stages of nephropathy in diabetic rats.Material and Methods: Sixty male albino rats were used and divided into the following groups; non-diabetic control group, diabetic nephropathy group and insulin-treated diabetic nephropathy group. By the end of the experimental period, 24 hours urine samples were collected to measure urine volume & urinary creatinine concentration and calculation of creatinine clearance. Then systolic blood pressure (SBP) was measured using rat tail sphygmomanometer technique. Fasting blood samples were collected for estimation of glycemic state, liver function tests and renal function tests. Finally both kidneys were fixed in 10% formalin solution for histopathology by using H&E & periodic acid schiffe (PAS).Results: Our data showed that streptozotocin injection significantly elevated glycemic state, aspartate transaminase (AST), alanine transaminase (ALT), serum urea, serum creat-inin, SBP and significantly decreased seum albumin, creatinin clearance, total and direct bilirubin. Alkaline phosphatase (ALP) and serum albumin showed insignificant change. Histopathological examination of the same group showed slight thickening of the basement membrane, arterioles, few inflammatory cells and hydropic changes in renal tubules. Insulin treatment significantly decreased glycemic state, AST, ALT, serum urea, serum creatinin, SBP and significantly elevated seum albumin, creatinin clearance, total and direct bilirubin. Histopathological examination of the same group showed some healthy glomeruli but still hydropic changes in renal tubules.Conclusion: Regular monitoring of bilirubin in diabetic patients is essential marker for progression and prognosis of diabetic nephropathy and effect of treatment.

The effects of maternal diabetes and insulin treatment on neurogenesis in the developing hippocampus of male rats

Diabetes in pregnancy is associated with an increasing risk of congenital malformations and central nervous system disorders (CNS) especially hippocampal neuronal circuitry disruption as a discreet region involved in neurogenesis phenomenon. This study aimed to investigate the effect of maternal diabetes and insulin treatment on the expression and distribution pattern of NeuN and DCX as two important markers of neurogenesis paradigm in developing rat hippocampus. All animals were randomly divided into three groups as follows: Control group, Diabetic (STZ-D), Diabetic treated with insulin (STZ-INS). Diabetes was induced in Wistar female rats by Sterptozotocin intraperitoneal injection (single does). Following confirmation of diabetes, animals were mated with non-diabetic males. Four to six units of protamine-Zinc insulin were delivered subcutaneously (SC) in insulin treated group. At the post-natal day 14 (P14), the brain of male offspring’s were removed for further study. In fact Immunofluorescence staining and Real time − PCR assays are used for evaluation of neurogenesis phenomenon. Our results showed a significant higher level of hippocampal DCX expression and an increase in the mean number of DCX positive cells in the DG of diabetic group male offspring (P < 0.05). We also found an insignificant up-regulation in the expression of DCX and the mean number of positive cells in the insulin-treated diabetic group neonates as compared to control group (P > 0.05). Nevertheless the results of immunofluorescence staining for NeuN also indicated that the mean number of NeuN+ cells was significantly lower in dentate gyrus of diabetic group male offspring (P < 0.05). Besides, there were significant down- regulation in the hippocampal mRNA expression of NeuN in diabetic pups compare to control (P < 0.05 each). Our results revealed that diabetes during pregnancy has an adverse effect on the hippocampal neurogenesis in rat neonates. Furthermore, the control of glycemia by insulin is sufficient to prevent the alterations in expression of neurogenesis markers.

Modulatory Effect of Concomitant Administration of Insulin and Vanadium on Inflammatory Biomarkers in Type 2 Diabetic Rats: Role of Adiponectin.

The aim of this study is to investigate the effect of vanadium and/or insulin on the proinflammatory biomarkers in type 2 diabetes mellitus (T2DM) rat model. Sixty male Sprague Dawley rats were divided into six groups (n = 10). Control group, control vanadium group, T2DM group, insulin-treated diabetic group, vanadium-treated diabetic group, and concomitant insulin and vanadium-treated diabetic group. At the end of the experiment, serum glucose, insulin, lipid profile, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), high sensitivity C reactive protein (hs- CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and adiponectin were measured. Administration of insulin and/or vanadium significantly decreased in the plasma levels of glucose, lipid profile, TNF-α, IL-6, hs-CRP, ICAM-1, and VCAM-1 with significant increase in adiponectin in comparison to the diabetic group. Concomitant administration of insulin and vanadium significantly improved the above measured parameters compared to either insulin or vanadium treatment. Based on our results we can conclude that administration of both vanadium and insulin reduced the low-grade systemic inflammation in T2DM, through reduction of both proinflammatory cytokines and adhesion molecules and increase adiponectin.

Anti-Diabetic Effects of Amygdalus Lycioides Spach in Streptozocin-Induced Diabetic Rats.

Diabetes mellitus is a group of metabolic disorders characterized by elevated blood sugar and abnormalities in insulin secretion and action. There are many anti-diabetic plants, which might supply useful sources for developing new medicines that can be used in treatment of diabetes mellitus. The primary objective of the present investigation is to evaluate the anti-diabetic properties of the aerial parts of Amygdalus lycioides in streptozocin-induced diabetic rats. Sixty rats were divided into 6 groups: streptozocin-induced diabetic control, insulin-treated diabetic group, and four Amygdalus lycioides-treated diabetic groups (125, 250, 500, and 1000 mg/kg/day). After 2 weeks of plant extract administration, the effects of extracts on blood glucose, body weight, BUN, creatinine, total cholesterol, LDL, HDL, triglyceride, total protein, Na, K, and plasma enzymes (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase) were analyzed. The pancreas of rats was also stained for stereological studies. Phytochemical evaluation of this extract showed the presence of flavonoids and tannins compounds. Glucose serum levels and glucose tolerance test showed a decrease in treatment with Amygdalus lycioides (1000 mg/kg). Serum total cholesterol, LDL, triglyceride, creatinine and alkaline phosphatase levels were decreased significantly by the extract but aspartate aminotransferase found to be increased after treatment. The total number and numerical density of beta cells increased in the Amygdalus lycioides group (1000 mg/kg). It seems that Amygdalus lycioides may act as a potential drug to treat diabetes and its complications. However, more investigations should be done to more clarify these results.

Insulin treatment restores islet microvascular vasomotion function in diabetic mice.

The microcirculation plays an important role in the pathogenesis of diabetes and its complications. We hypothesized that pancreatic islet microvascular (PIM) vasomotion, as a parameter of pancreatic islet microcirculation function, is abnormal in diabetic mice and that insulin treatment may reverse this dysfunction. Mice were randomly assigned to non-diabetic control, untreated diabetic, and insulin-treated diabetic groups (n = 6 in each group). Separate groups of streptozotocin (STZ)-induced diabetic and high-fat diet-fed mice were used as a model of hyperglycemia. Insulin-treated diabetic mice were treated with 1-1.5 IU/day insulin for 1 week. Laser Doppler monitors were used to evaluate PIM vasomotion. Morphological and ultrastructural changes in islet endothelial cells were determined by immunohistochemistry and transmission electron microscopy. Glucagon, insulin, vascular endothelial growth factor (VEGF)-A, and platelet endothelial cell adhesion molecule (PECAM-1) expression was determined by immunohistochemistry and Western blotting. In both untreated diabetic groups, the pancreatic islet microcirculation was unable to regulate PIM vasomotion. The rhythm of vasomotion was irregular, and the average blood perfusion, amplitude, frequency, and relative velocity of vasomotion were significantly lower than in non-diabetic controls. Insulin treatment restored the functional status of PIM vasomotion. In islet endothelial cells from both untreated diabetic groups, the mitochondria were swollen with disarrangement of the cristae, and the distribution of PECAM-1 was discontinuous. Insulin treatment significantly increased the reduced expression of PECAM-1 in both untreated diabetic groups and VEGF-A expression in untreated STZ-diabetic mice. The results suggest that the functional status of PIM vasomotion is impaired in diabetic mice but can be restored by insulin.

Diabetes during pregnancy enhanced neuronal death in the hippocampus of rat offspring

BackgroundDiabetes in pregnancy has a detrimental effect on central nervous system (CNS) development and is associated with an increased risk of short- and long-term neurocognitive impairment in the offspring. This study aimed to investigate the effect of maternal diabetes and also insulin treatment on the numerical density of apoptotic cells in rat neonate’s hippocampi during the first two postnatal weeks. MethodsWistar female rats were maintained diabetic from a week before gestation through parturition and their male pup’s brains were collected at postnatal days (P); P0, P7 and P14, equivalent to the third trimester in human. Numerical density of total neurons and percentage of apoptotic (TUNEL-positive) cells in different subfields of hippocampus (CA1, CA2, CA3, and DG) was calculated by stereological methods. ResultsImmediately after birth, we found a significantly decline in the total neuronal density only in hippocampal CA3 area in neonates born to diabetic animals (p<0.0001). Moreover, the number of neurons was significantly decreased in all hippocampal sub-regions of diabetic group pups when compared to control and insulin treated diabetic pups at both P7 and P14 (p<0.0001 each). Nevertheless, in diabetic group, the percentage of apoptotic cells in different subfields of hippocampus were higher in all studied time-points compared to control or insulin treated diabetic groups (p<0.0001 each). There were no significant differences either in the total number or apoptotic cells in the different hippocampal sub-fields between the insulin-treated diabetic group and controls (p>0.05). ConclusionOur data indicate that diabetes in pregnancy induce the neuronal cell apoptosis in offspring hippocampus. Furthermore, the maternal glycaemia control by insulin treatment in the most cases normalized these effects.

Stereological study of the effects of maternal diabetes on cerebellar cortex development in rat

Diabetes during pregnancy is associated with the deficits in balance and motor coordination and altered social behaviors in offspring. In the present study, we have investigated the effect of maternal diabetes and insulin treatment on the cerebellar volume and morphogenesis of the cerebellar cortex of rat neonates during the first two postnatal weeks. Sprague Dawley female rats were maintained diabetic from a week before pregnancy through parturition. At the end of pregnancy, the male offspring euthanized on postnatal days (P) 0, 7, and 14. Cavalieri's principle and fractionator methods were used to estimate the cerebellar volume, the thickness and the number of cells in the different layers of the cerebellar cortex. In spite of P0, there was a significant reduction in the cerebellar volume and the thickness of the external granule, molecular, and internal granule layers between the diabetic and the control animals. In diabetic group, the granular and purkinje cell densities were increased at P0. Moreover, the number of granular and purkinje cells in the cerebellum of diabetic neonates was reduced in comparison with the control group at P7 and P14. There were no significant differences in either the volume and thickness or the number of cells in the different layers of the cerebellar cortex between the insulin-treated diabetic group and controls. Our data indicate that diabetes in pregnancy disrupts the morphogenesis of cerebellar cortex. This dysmorphogenesis may be part of the cascade of events through which diabetes during pregnancy affects motor coordination and social behaviors in offspring.

Effect of maternal diabetes on gliogensis in neonatal rat hippocampus.

Background:Diabetes in pregnancy is a common metabolic disorder associated with various adverse outcomes in the offspring including impairments in attention and memory and alterations in social behavior. Glial cells are proven to have a critical role in normal function of neurons, and alteration in their activity could contribute to disturbance in the brain function. The aim of this study was to investigate the effect of maternal diabetes on hippocampal mRNA expression and distribution pattern of glial fibrillary acidic protein (GFAP) immunoreactive glial cells in the dentate gyrus (DG) of rat neonate at postnatal day 14 (P14).Materials and Methods:Wistar female rats were randomly allocated in control, diabetic, and insulin-treated diabetic groups. Diabetes was induced by injection of streptozotocin from 4 weeks before gestation until parturition. After delivery, the male offspring was euthanized at P14.Results:Our results showed a significant higher level of hippocampal GFAP expression and an increase in the mean number of GFAP positive cells in the DG of diabetic group offspring (P < 0.05). We also found an insignificant up-regulation in the expression of GFAP and the mean number of positive cells in the insulin-treated diabetic group neonates as compared to control group (P > 0.05).Conclusion:The present study revealed that diabetes during pregnancy strongly increased the glial cells production in the developing rat hippocampus.

The effects of ozone therapy on caspase pathways, TNF-α, and HIF-1α in diabetic nephropathy.

Accelerated apoptosis plays a vital role in the development of diabetic vascular complications. Ozone may attenuate diabetic nephropathy by means of decreased apoptosis-related genes. The aim of our study was to investigate the effect of ozone therapy on streptozotocin-induced diabetic nephropathy in rats. Also the histopathological changes in diabetic kidney tissue with ozone treatment were evaluated. The rats were randomly divided into six groups (n = 7): control (C), ozone (O), diabetic (D), ozone-treated diabetic (DO), insulin-treated diabetic (DI), and ozone- and insulin-treated diabetic (DOI). D, DI, and DOI groups were induced by a single intraperitoneal injection of streptozotocin. Ozone was given to the O, DO, and DOI groups. Group DI and DOI received subcutaneous (SC) insulin (3 IU). All animals received daily treatment for 6 weeks. Expressions of caspase-1-3-9, HIF-1α, and TNF-α genes were significantly higher in D group compared to C group (p < 0.05 for all). Ozone treatment resulted in significant decrease in the expressions of these genes in diabetic kidney tissue compared to both C and D group (p < 0.05 for all). Caspase-1-3-9, HIF-1α, and TNF-α gene expressions were found to be lower in DOI group compared to C group (p < 0.05 for all). Also adding ozone treatment to insulin therapy resulted in more significantly decrease in the expressions of these genes in diabetic tissue compared to only insulin-treated diabetic group (p < 0.05 for all). Regarding histological changes, ozone treatment resulted in decrease in the renal corpuscular inflammation and normal kidney morphology was observed. Both insulin and ozone therapies apparently improved kidney histological findings with less degenerated tubules and less inflammation of renal corpuscle compared to D, DO, and DI groups. Ozone therapy decreases the expressions of apoptotic genes in diabetic kidney tissue and improves the histopathological changes.

Insulin-Like Growth Factor-1 Receptor Is Differentially Distributed in Developing Cerebellar Cortex of Rats Born to Diabetic Mothers.

Insulin-like growth factor-1 (IGF-1) has an important role in development of the central nervous system (CNS). Maternal diabetes is associated with a higher risk of developmental abnormalities in their offspring including motor dysfunction and learning deficits. The present study aimed to investigate the effects of maternal diabetes on the distribution pattern of IGF-1 receptor (IGF-1R) in the developing rat cerebellar cortex. Wistar female rats were maintained diabetic from a week before pregnancy through parturition, and male offspring was killed at P0, P7, and P14. In spite of P0, there was a significant increase in the total cerebellar volume in the pups born to diabetic mothers. In diabetic group, the IGF-1R+ granular cell densities in internal granular (IGL) and molecular (ML) layers were increased at P0. Moreover, the number of positive granular and Purkinje cells in the IGL of diabetic neonates' cerebellum was reduced in comparison with the control group at P7 and P14. There were no differences either in volume or in the number of IGF-1R+ cells in the layers of the cerebellar cortex between the insulin-treated diabetic group and controls. Our data indicate that diabetes in pregnancy strikingly influence the localization of IGF-1R in the developing cerebellar cortex.

Trophic actions of oral vanadium and improved glycemia on the pancreatic beta-cell ultrastructure of streptozotocin-induced diabetic rats.

Oral vanadyl sulfate (vanadium) has potent hypoglycemic effects in diabetes animals, but data about its actions on pancreatic beta-cells (BC) ultrastructure is limited. Partial diabetic rats were treated with vanadium and insulin injection and their effects on BC ultrastructure are studied. Male rats were made diabetic with intravenous streptozotocin injection (STZ, 40 mg/kg). Animals were randomly divided to control (CD), vanadium-treated (1 mg/mL VOSO4 + 5H2O in base solution, VTD) and insulin-treated (80 U/kg/day NPH insulin injection, ITD) diabetic groups. Treatments started 10 days after STZ injection and terminated after 2 months. Intermittent tail blood samples were taken for measurements of blood glucose (BG) and plasma insulin (PI). Finally animals were sacrificed and pancreata prepared for assessments of BC ultrastructure, islets histology and insulin immunoreactivity (IIR). Vanadium decreased BG (P&lt;0.0001), elevated the reduced PI (P&lt;0.001), prevented islet atrophy and restored BC ultrastructure. Low BG seen during treatment in VTD and ITD only persisted in VTD after vanadium withdrawal. Hyperglycemia worsened in CD and repaired in ITD shortly after insulin withdrawal. CD islets were atrophied, had scattered IIR spots. BC had pyknotic nuclei, vacuolated cytoplasm and few tiny insulin secretory granules. VTD islets looked normal with compact centered IIR spots. BC had well-developed endoplasmic reticulum, many insulin secretory granules and mitochondria. ITD islet structure was slightly better than CD and BC had some immature insulin secretory granules. The trophic actions of vanadium in diabetic rats effectively renovated beta cell ultrastructure and prevented pancreatic islets atrophy, whereas the relief of glucotoxicity seen with insulin treatment could repair some beta cells and partially prevented islet atrophy.

An extract from date seeds stimulates endogenous insulin secretion in streptozotocin-induced type I diabetic rats

Background: The efficacy of an extract from date seeds has been tested successfully on the glycemic control of type I diabetes mellitus in rats. A suggestion that date seed extract could stimulate certain cells to differentiate into insulin-secreting cells has been proposed. In order to investigate such a possibility, this study was conducted to measure C-peptide levels in the serum of type 1 diabetic rats treated with date seed extract.Methods: Two hundred rats were divided into 4 groups. Group I served as the control. Group II was given daily ingestions of 10 ml of date seed extract. Groups III and IV were made diabetic by streptozotocin injection and were given daily subcutaneous injections of 3 IU/day of insulin for 8 weeks. Group IV received, in addition, daily ingestions of 10 ml of seed extract. At the end of experiment, blood samples were collected from each rat, and blood glucose and serum C-peptide levels were measured.Results: No significant differences in the means of blood glucose and serum C-peptide levels were observed between groups I (control group) and II (date seed extract-treated control group). Group IV (date seed extract-insulin-treated diabetic group) showed a statistically significant reduction in the mean blood glucose level compared to Group III (insulin-treated diabetic group). The mean serum C-peptide level was significantly higher in group IV compared to group III.Conclusion: Biochemical results suggested an increase in endogenous insulin secretion in the case of type 1 diabetic rats treated with date seed extract, which might be the cause of its hypoglycemic effect.Keywords: Date seed extract; type 1 diabetes; serum C-peptide

Molecular events on tooth socket healing in diabetic rabbits

Healing of extraction sockets involves complex cellular events such as repair and regeneration of tissue. These events are precisely controlled and regulated by specific signalling molecules such as transforming growth factor beta (TGF-β), vascular endothelial growth factor (VEGF), bone morphogenetic protein (BMP), and insulin-like growth factor (IGF), which are well-conserved proteins involved in the initial response to injury and repair in soft and hard tissues. We studied 48 rabbits, which were divided into 3 groups of 16 each: the control group, the untreated diabetic group, and the insulin-treated diabetic group. The lower incisor of each rabbit was extracted and, after 2, 10, 20, and 30 days of healing, the expression of TGFβ-3, VEGF, IGF-1R, and BMP-4 in the sockets was measured immunohistochemically. Rabbits with untreated diabetes expressed less TGFβ-3 than the other groups throughout the healing periods, whereas IGF-1R expression was higher than that in the other groups. This increase in IGF-1R expression was responsible for increasing the healing time in rabbits in the untreated group. The healing of bone in diabetic rabbits that were not treated with insulin was prolonged because of a delay in the onset of cell proliferation and osteoblast differentiation, and the insulin treatment had a direct effect on the expression of TGFβ-3 and IGF-1R, which accelerated healing of the socket.