cytochrome-c-t and Diabetes-Mellitus--Type-1

The upregulation of reactive oxygen species (ROS) is a primary cause of cardiomyocyte apoptosis in diabetes cardiomyopathy (DCM). Mitofusin-2 (Mfn-2) is a key protein that bridges the mitochondria and endoplasmic reticulum (ER). Hydrogen sulfide (H

Topics: Animals; Apoptosis; Blood Glucose; Blotting, Western; Cytochromes c; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Cardiomyopathies; Endoplasmic Reticulum; Endoplasmic Reticulum Stress; Fluorescent Antibody Technique; Gasotransmitters; GTP Phosphohydrolases; Heart; Hydrogen Sulfide; In Situ Nick-End Labeling; Male; Membrane Proteins; Microscopy, Electron; Mitochondria, Heart; Mitochondrial Proteins; Myocardium; Myocytes, Cardiac; Rats; Rats, Wistar; Sulfides

Topics: AMP-Activated Protein Kinases; Animals; Apoptosis; Cardiotonic Agents; Cytochromes c; Cytosol; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Glucose; Glucose Tolerance Test; Male; Melatonin; Mice; Mitochondria; Myocardial Reperfusion Injury; Myocardium; Oxidative Stress; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Rats, Sprague-Dawley; RNA, Small Interfering; Signal Transduction; Sirtuin 3; Streptozocin; Superoxide Dismutase; Transcription Factors

Vascular inflammation and cardiac dysfunction are the leading causes of mortality and morbidity among the diabetic patients. Type 1 diabetic mellitus (T1DM) is associated with increased cardiovascular complications at an early stage of the disease. The purpose of the present study was to explore whether arjunolic acid (AA) plays any protective role against cardiovascular complications in T1DM and if so, what molecular pathways it utilizes for the mechanism of its protective action. Streptozotocin (STZ) was used to induce T1DM in experimental rats. Alteration in plasma lipid profile and release of membrane bound enzymes like LDH (lactate dehydrogenase) and CK (creatine kinase) established the association of hyperlipidemia and cell membrane disintegration with hyperglycemia. Hyperglycemia altered the levels of oxidative stress related biomarkers, decreased the intracellular NAD and ATP concentrations. Hyperglycemia-induced enhanced levels of VEGF, ICAM-1, MCP-1 and IL-6 in the plasma of STZ treated animals indicate vascular inflammation in T1DM. Histological studies and FACS analysis revealed that hyperglycemia caused cell death mostly via the apoptotic pathway. Investigating molecular mechanism, we observed NF-κB and MAPKs (p38 and ERK1/2) activations, mitochondrial membrane depolarization, cytochrome C release, caspase 3 activation and PARP cleavage in apoptotic cell death in the diabetic cardiac tissue. Treatment with AA (20 mg/kg body weight) reduced hyperglycemia, membrane disintegration, oxidative stress, vascular inflammation and prevented the activation of oxidative stress induced signaling cascades leading to cell death. Results suggest that AA possesses the potential to be a beneficial therapeutic agent in diabetes and its associated cardiac complications.

Topics: Animals; Antioxidants; Apoptosis; Chemokine CCL2; Cytochromes c; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Flow Cytometry; Hypoglycemic Agents; Intercellular Adhesion Molecule-1; Interleukin-6; Male; Mitochondria; Mitochondrial Membranes; Oxidative Stress; Rats; Reactive Oxygen Species; Signal Transduction; Triterpenes; Vascular Endothelial Growth Factor A

In pancreatic islets, free radical formation produced upon exposure to proinflammatory cytokines mediates β cell destruction, which ultimately leads to type 1 diabetes (T1D). In this study, we examined whether laccase, a family of the blue copper protein, can be successfully used to prevent β cells from cytokine-mediated apoptosis. Non-obese diabetic (NOD) mice were used for these experiments. In parallel, the RINm5f β cell line was employed as a model system for in vitro experiments. The results demonstrated that laccase effectively scavenged peroxinitrite, which can be formed by nitric oxide, and upregulated the expression of antioxidant enzymes, such as manganese superoxide dismutase (MnSOD) and catalase. Interestingly, laccase balanced pro- (Bax) and anti-apoptotic (Bcl-2) proteins in terms of both the mRNA and protein levels with a downregulation of cytochrome c protein in RINm5f cells. In addition, laccase maintained blood glucose concentrations at a normal level with a simultaneous increase in plasma insulin levels during the spontaneous induction of diabetes in NOD mice. In conclusion, the antioxidant potentials of laccase in scavenging free radicals and upregulation of antioxidant enzymes may exert its pro-survival effect by counteracting the increased intracellular oxidative stress, and, consequently, by inhibiting apoptosis induced by cytokine-mediated activation during the course of T1D.

Topics: Animals; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Blood Glucose; Cytochromes c; Cytokines; Diabetes Mellitus, Type 1; Female; Insulin; Insulin-Secreting Cells; Laccase; Mice; Mice, Inbred NOD; Oxidative Stress; Peroxynitrous Acid; Phytotherapy; Polyporales; Rats; Up-Regulation

Increasing evidences in both experimental and clinical studies suggest that oxidative stress is involved in the pathogenesis of diabetic tissue damage. Pancreatic beta-cell death is the cause of decreased insulin production in diabetes. Streptozotocin (STZ) is widely used to induce experimental diabetes due to its ability to selectively target and destroy insulin producing pancreatic beta-cells via the formation of both reactive oxygen species (ROS) and RNS (reactive nitrogen species). This study investigated the prophylactic role of arjunolic acid (AA) against STZ-induced diabetes in the pancreas tissue of the Swiss albino rats (as a working model). We observed that STZ administration (at a dose of 65mg/kg body weight, injected in the tail vain) caused increased production of both ROS and RNS in the pancreas tissue of experimental animals. Formation of these reactive intermediates decreased the intracellular antioxidant defense, increased the levels of lipid peroxidation, protein carbonylation, serum glucose and TNF-alpha. Investigating the signaling pathways, we found that STZ administration caused the activation of phospho-ERK1/2, phospho-p38, NF-kappaB and destruction of mitochondrial transmembrane potential, release of cytochrome c as well as activation of caspase 3 in the pancreas tissue keeping the levels of total ERK1/2 and p38 significantly unchanged. Treatment of animals with AA (at a dose of 20mg/kg body weight, orally) both prior and post to the STZ administration effectively reduced these adverse effects by inhibiting the excessive ROS and RNS formation as well as by down-regulating the activation of phospho-ERK1/2, phospho-p38, NF-kappaB and mitochondrial dependent signal transduction pathways leading to apoptotic cell death. Combining all, these results suggest that AA plays some beneficial roles against STZ-induced diabetes.

Topics: Animals; Antioxidants; Apoptosis; Blood Glucose; Caspase 3; Cytochromes c; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Dose-Response Relationship, Drug; Hypoglycemic Agents; Lipid Peroxidation; Male; Membrane Potential, Mitochondrial; Mitochondria; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; NF-kappa B; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Pancreas; Phosphorylation; Protein Carbonylation; Rats; Reactive Nitrogen Species; Reactive Oxygen Species; Time Factors; Triterpenes; Tumor Necrosis Factor-alpha

To investigate the expression of the antiapoptotic and proapoptotic markers in diabetic retinas.. In total, 12 donor eyes from six subjects with diabetes mellitus, and 10 eyes from five nondiabetic subjects without known ocular disease serving as control subjects were examined. Immunohistochemical techniques were used with antibodies directed against cyclooxygenase-2 (Cox-2), Akt (protein kinase B), Mcl-1, Bad, cytochrome c, apoptosis-inducing factor (AIF), tumour necrosis factor receptor-1-associated death domain protein (TRADD), and Fas-associated death domain protein (FADD).. In retinas from all subjects without diabetes, cytoplasmic immunoreactivity for the antiapoptotic molecules Cox-2, Akt, and Mcl-1 was noted in ganglion cells. Cytoplasmic immunostaining for Cox-2 was also noted in the retinal pigment epithelial cells. Weak immunoreactivity for the mitochondrial apoptogenic proteins cytochrome c, and AIF was noted in the inner segments of photoreceptors, in the inner one-third of the outer plexiform layer, in cells in the inner nuclear layer, in the inner plexiform layer, and in ganglion cells. There was no immunoreactivity for the other antibodies tested. All diabetic retinas showed de novocytoplasmic immunoreactivity for Bad in ganglion cells, and in occasional cells in the inner nuclear layer. Upregulation of cytochrome cand AIF immunoreactivity was noted. Cox-2, Akt, and Mcl-1 immunoreactivity was not altered in the diabetic retinas. There was no immunoreactivity for TRADD, and FADD.. Ganglion cells in diabetic and nondiabetic retinas express the antiapoptotic molecules Cox-2, Akt, and Mcl-1. Retinal ganglion cells express the proapoptotic molecule Bad in response to diabetes-induced neuronal injury. Diabetic retinas show upregulation of the mitochondrial proteins cytochrome c, and AIF.

Topics: Aged; Apoptosis; Apoptosis Inducing Factor; bcl-Associated Death Protein; Biomarkers; Cyclooxygenase 2; Cytochromes c; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Fas-Associated Death Domain Protein; Female; Humans; Immunohistochemistry; Male; Middle Aged; Myeloid Cell Leukemia Sequence 1 Protein; Neoplasm Proteins; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Retina; TNF Receptor-Associated Death Domain Protein