Vanillylacetone attenuates cadmium chloride-induced hippocampal damage and memory loss through up-regulation of nuclear factor erythroid 2-related factor 2 gene and protein expression.

JOURNAL/nrgr/04.03/01300535-202412000-00030/figure1/v/2024-04-08T165401Z/r/image-tiff Memory loss and dementia are major public health concerns with a substantial economic burden. Oxidative stress has been shown to play a crucial role in the pathophysiology of hippocampal damage-induced memory impairment. To investigate whether the antioxidant and anti-inflammatory compound vanillylacetone (zingerone) can protect against hippocampal damage and memory loss induced by cadmium chloride (CdCl2) administration in rats, we explored the potential involvement of the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, which is known to modulate oxidative stress and inflammation. Sixty healthy male Wistar rats were divided into five groups: vehicle-treated (control), vanillylacetone, CdCl2, vanillylacetone + CdCl2, vanillylacetone + CdCl2 + brusatol (a selective pharmacological Nrf2 inhibitor) groups. Vanillylacetone effectively attenuated CdCl2-induced damage in the dental gyrus of the hippocampus and improved the memory function assessed by the Morris Water Maze test. Additionally, vanillylacetone markedly decreased the hippocampal tissue levels of inflammatory biomarkers (interleukin-6, tumor necrosis factor-α, intracellular cell adhesive molecules) and apoptosis biomarkers (Bax and cleaved caspase-3). The control and CdCl2-treated groups treated with vanillylacetone showed reduced generation of reactive oxygen species, decreased malondialdehyde levels, and increased superoxide dismutase and glutathione activities, along with significant elevation of nuclear Nrf2 mRNA and protein expression in hippocampal tissue. All the protective effects of vanillylacetone were substantially blocked by the co-administration of brusatol (a selective Nrf2 inhibitor). Vanillylacetone mitigated hippocampal damage and memory loss induced by CdCl2, at least in part, by activating the nuclear transcription factor Nrf2. Additionally, vanillylacetone exerted its potent antioxidant and anti-inflammatory actions.

Captopril inhibits thioacetamide-induced chronic liver injury associated with the suppression of inflammation / hypoxia- inducible factor 1-alpha / profibrogenic axis-mediated hepatotoxicity in rats / Captopril inhibe la lesión hepática crónica inducida por tioacetamida asociada con la supresión de la inflamación/factor 1-alfa inducible por hipoxia/hepatotoxicidad mediada por el eje profibrogénico en rata

SUMMARY: Liver transplantation is the only available method to treat liver failure induced by chronic liver injury. We sought to determine whether the angiotensin-converting enzyme inhibitor, captopril, can inhibit the development of chronic liver injury induced by the hepatotoxic agent thioacetamide (TAA) in association with the suppression of inflammation (hsCRP, TNF-α, and IL-6) / hypoxia- inducible factor 1-alpha (HIF-1α) / profibrosis (TIMP-1, MMP-9, and α-SMA) axis that mediates liver injury. Therefore, the model group of rats was injected for eight weeks with 200 mg/kg TAA starting at week two. The protective group was pretreated with 150 mg/ kg captopril daily for two weeks prior to TAA injections and continued receiving both capropril and TAA agents until being humanely scrificed at week 10. We observed a substantial damage to liver tissue in the model group as demonstrated by a significant (p<0.0001) increase in blood and hepatic tissue levels of high sensitivity C-reactive protein (hsCRP), tumor necrosis factor-a (TNF-α), interleukin- 6 (L-6), HIF-1α, tissue inhibitor of metalloproteinases-1 (TIMP-1), matrix metalloproteinase-9 (MMP-9), alpha-smooth muscle actin (α-SMA), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). All these parameters were significantly (p<0.0244) protected by captopril. Also, a significant (p<0.0001) positive correlation was observed between a-SMA (profibrosis) and the serum and tissue levels of hsCRP, TNF-α, HIF-1α, TIMP-1, MMP-9, and ALT. Thus, these findings suggest that the induction of chronic liver injury by the hepatotoxic compound, TAA is associated with the upregulation of inflammation/HIF-1α/profibrosis, with captopril exhibiting beneficial hepatic pleotropic effects.

El trasplante de hígado es el único método disponible para tratar la insuficiencia hepática inducida por una lesión hepática crónica. Buscamos determinar si el inhibidor de la enzima convertidora de angiotensina, captopril, puede inhibir el desarrollo de lesión hepática crónica inducida por el agente hepatotóxico tioacetamida (TAA) en asociación con la supresión de la inflamación (hsCRP, TNF-α e IL-6) / factor inducible por hipoxia 1-alfa (HIF-1α) / profibrosis (TIMP-1, MMP-9 y α- SMA) eje que media la lesión hepática. Por lo tanto, al grupo modelo de ratas se le inyectó durante ocho semanas 200 mg/kg de TAA a partir de la semana dos. El grupo protector fue pretratado con 150 mg/kg de captopril al día durante dos semanas antes de las inyecciones de TAA y continuó recibiendo capropril y agentes TAA hasta que fue sacrificado en la semana 10. Observamos un daño sustancial en el tejido hepático en el grupo modelo, como lo demuestra un aumento significativo (p<0,0001) de los niveles en sangre y tejido hepático de proteína C reactiva de alta sensibilidad (hsCRP), factor de necrosis tumoral-α (TNF-a), interleucina-6 (L-6), HIF-1α, inhibidor tisular de metaloproteinasas-1 (TIMP-1), metaloproteinasa de matriz-9 (MMP-9), actina de músculo liso alfa (α-SMA), alanina aminotransferasa (ALT) y aspartato aminotransferasa (AST). Todos estos parámetros estaban significativamente (p<0,0244) protegidos por captopril. Además, se observó una correlación positiva significativa (p<0,0001) entre α-SMA (profibrosis) y los niveles séricos y tisulares de hsCRP, TNF-α, HIF-1α, TIMP- 1, MMP-9 y ALT. Por lo tanto, estos hallazgos sugieren que la inducción de daño hepático crónico por el compuesto hepatotóxico, TAA, está asociada con la regulación al alza de la inflamación/HIF-1α/profibrosis, con captopril exhibiendo efectos pleotrópicos hepáticos beneficiosos.

Metformin ameliorates ROS-p53-collagen axis of fibrosis and dyslipidemia in type 2 diabetes mellitus-induced left ventricular injury.

BACKGROUND: The link between oxidative stress (ROS), apoptosis (p53) and fibrosis (collagen) in type 2 diabetes mellitus (T2DM)-induced cardiac injury in the presence and absence of the antidiabetic drug, metformin has not been investigated before. MATERIAL AND METHODS: T2DM was induced in rats by a combination of high carbohydrate and fat diets (HCFD) and streptozotocin (50 mg/kg) injection. The protection group started metformin (200 mg/kg) treatment 14 days prior to the induction of diabetes and continued on metformin and HCFD until being sacrificed at week 12. RESULTS: Diabetes significantly induced blood levels of ROS and left ventricular p53 and collagen expression that was inhibited by metformin. Metformin also significantly reduced glycated haemoglobin and dyslipidemia induced by diabetes. In addition, a significant correlation between ROS-p53-collagen axis and glycaemia and hyperlipidaemia was observed. CONCLUSIONS: These findings show that metformin provides substantial protection against diabetic cardiomyopathy-induced ROS-p53 mediated fibrosis and dyslipidemia.

Vanadyl sulphate ameliorates biomarkers of endothelial injury and coagulation and thrombosis in a rat model of hyperglycaemia.

BACKGROUND: We sought to determine whether the insulin mimicking agent, vanadyl sulphate (Van) can inhibit biomarkers of endothelial injury and coagulation and thrombosis induced by a moderate level of hyperglycaemia. MATERIAL AND METHODS: Hyperglycaemia was induced in rats by a single injection of streptozotocin (STZ, 50 mg/kg) two weeks after being fed on a high-fat diet (model group). The treatment group started Van (20 mg/kg/day) treatment one-week post STZ injection and continued on Van until being sacrificed at week 10. RESULTS: Administration of Van to the model group significantly (p < .05) ameliorated dyslipidemia and biomarkers of inflammation (TNF-α, IL-6, and hsCRP) and endothelial injury (E-selectin, P-selectin, sICAM-1, sVCAM-1, and ET-1). Van also significantly inhibited hyperglycaemia-induced blood levels of coagulation (vWF) and thrombosis (PAI-1 and fibrinogen) biomarkers. CONCLUSIONS: Vanadyl sulphate effectively suppresses hyperglycaemia-induced endothelial injury, coagulation and thrombosis, which is associated with the inhibition of inflammation and dyslipidemia.

Quercetin Inhibits ROS-p53-Bax-caspase-3 axis of apoptosis and augments gonadotropin and testicular hormones in chronic unpredictable stress-Induced testis injury / La quercetina inhibe el eje de apoptosis ROS-p53-Bax-caspasa-3 y aumenta la gonadotropina y las hormonas testiculares en la lesión testicular inducida por estrés crónico e impredecible

SUMMARY: A large body of evidence supports the protective role of the flavonol antioxidant compound quercetin in mammals. We tested the hypothesis that quercetin can protect against the hypothalamus-pituitary-gonadal (HPG) axis defect like a reduction in gonadotropins and testicular hormones and abnormal semen analysis induced by chronic unpredictable stress (CUS), possibly via the downregulation of oxidative stress (ROS) and p53-Bax-caspase-3 pathways. Rats were either exposed to a variety of unpredictable stressors daily before being sacrificed after 3 weeks (model group) or were treated with quercetin (50 mg/kg body weight/day) at the same time the CUS were induced (treated group). Harvested testicular tissues were stained with basic histological staining, and testis homogenates were assayed for the tumor suppressor p53, apoptosis regulator Bax, B-cell lymphoma 2 (Bcl-2), caspase-3, malondialdehyde (MDA), glutathione peroxidase (GPx), and superoxide dismutase (SOD). In addition, harvested epididymis tissues were used to assess semen analysis, and blood samples were assayed for the testicular hormone testosterone, the adrenal cortex hormone corticosterone, and the anterior pituitary gonadotropins, follicular stimulating hormone (FSH) and luteinizing hormone (LH). CUS induced profound testicular damage and significantly (p<0.05) induced p53, Bax, caspase-3, MDA, and corticosterone, which were significantly (p<0.05) inhibited by quercetin except corticosterone. Whereas, quercetin significantly (p<0.05) increased FSH, LH, testosterone, Bcl-2, GPx, and SOD levels that were inhibited by CUS. In addition, CUS induced oligozoospermia, asthenozoospermia, and teratozoospermia, which were significantly (p<0.05) protected by quercetin. Thus, Quercetin protects against CUS-induced HPG defects in rats, which is associated with the inhibition of ROS-p53-Bax-caspase-3 axis.

RESUMEN: El papel protector del compuesto antioxidante flavonol quercetina en los mamíferos ha sido ampliamente reportado. Probamos la hipótesis que la quercetina puede proteger contra el defecto del eje hipotálamo-hipofisiario- gonadal (HHG) como una reducción de gonadotropinas y hormonas testiculares y análisis de semen anormal inducido por estrés crónico impredecible (ECI), posiblemente a través de la regulación reducida del estrés oxidativo (REO) y las vías p53- Bax-caspasa-3. Las ratas fueron expuestas a una variedad de fac- tores estresantes impredecibles diariamente antes de ser sacrificadas después de 3 semanas (grupo modelo) o fueron tratadas con quercetina (50 mg / kg de peso corporal / día) al mismo tiempo que se indujo la ECI (grupo tratado). Los tejidos testiculares fueron teñidos con tinción histológica básica y los homogeneizados de testículo se analizaron para determinar el supresor de tumores p53, el regulador de apoptosis Bax, el linfoma de células B 2 (Bcl-2), la caspasa-3, el malondialdehído (MDA), la glutatión peroxidasa (GPx) y superóxido dismutasa (SOD). Además, se utilizaron tejidos del epidídimo recolectados para evaluar el análisis de semen y se analizaron muestras de sangre para determinar la hormona testicular testosterona, la hormona corticosterona de la corteza suprarrenal y las gonadotropinas de la hipófisis anterior, la hormona estimulante folicular (FSH) y la hormona luteinizante (LH). El ECI indujo daño testicular importante e indujo significativamente niveles de (p <0,05) p53, Bax, caspasa-3, MDA y corticosterona, que fueron inhibidos (p <0,05) por la quercetina. La quercetina aumentó significativamente (p <0,05) los niveles de FSH, LH, testosterona, Bcl-2, GPx y SOD que fueron inhibidos por ECI. Además, ECI indujo oligozoospermia, astenozoospermia y teratozoospermia, protegidos de manera significativa (p <0,05) por la quercetina. Por lo tanto, la quercetina protege contra los defectos de HHG inducidos por ECI en ratas, lo que está asociado con la inhibición del eje ROS-p53-Bax-caspasa-3.

Insulin protects against type 1 diabetes mellitus-induced aortopathy associated with the inhibition of biomarkers of vascular injury in rats.

BACKGROUND: We sought to investigate the protective effect of insulin against type 1 diabetes mellitus (T1DM)-induced aortic injury (aortopathy) associated with the inhibition of biomarkers of vascular injury. MATERIAL AND METHODS: T1DM was induced in rats by streptozotocin (STZ) (65 mg/kg), and the protection group started insulin treatment 2 days post diabetic induction and continued until being sacrificed at week 8. RESULTS: Aortopathy was developed in the diabetic rats as demonstrated by profound alterations to the aorta ultrastructure, which was substantially protected by insulin. In addition, insulin significantly inhibited diabetes-induced dyslipidaemia, soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1), oxidative stress, and inflammation. However, blood levels of these biomarkers in the insulin-treated group were still significant (p < .05) compared with the control group, whereas insulin treatment returned blood glucose and triglyceride to control levels. CONCLUSIONS: We demonstrate effective protection by insulin against T1DM-induced aortopathy in rats, which is associated with the inhibition of vascular injury biomarkers.

Induction of brain injury and depression in rats by chronic unpredictable stress associated with the augmentation of nitrosative stress and apoptosis / Inducción de lesión cerebral y depresión en ratas por estrés crónico impredecible asociado con el aumento del estrés nitrosativo y la apoptosis

SUMMARY: Repeated stress is a risk factor for memory impairment and neurological abnormalities in both humans and animals. We sought to investigate the extent of (i) brain tissue injury; (ii) nitrosative and oxidative stress in brain tissue homogenates; (iii) apoptotic and survival biomarkers in brain tissue homogenates; and (iv) immobility and climbing abilities, induced over a period of three weeks by chronic unpredictable stress (CUS). Wistar rats were either left untreated (Control group) or exposed to a variety of unpredictable stressors daily before being sacrificed after 3 weeks (model group). Assessment of depression-like behavior was performed and animals were then culled and harvested brain tissues were stained with basic histological staining and examined under light microscopy. In addition, brain tissue homogenates were prepared and assayed for these parameters; inducible nitric oxide synthase (iNOS), malondialdehyde (MDA), superoxide dismutase (SOD), caspase-3, and B-cell lymphoma 2 (Bcl-2). Histology images showed CUS induced profound damage to the cerebral cortex as demonstrated by severe neuronal damage with shrunken cells, disrupted atrophic nuclei, perineuronal vacuolation and swollen glial cells. CUS also significantly (p<0.05) induced iNOS, MDA, and caspase-3, whereas SOD and Bcl-2 brain tissue levels were inhibited by CUS. In addition, data from the depression-like behavior, forced swimming test showed significant (p<0.05) increase in animal immobility and decrease in climbing ability in the model group of rats. Thus, here we demonstrated a reliable rat model of chronic stress-induced brain injury, which can further be used to investigate beneficial drugs or agents used for a period of three weeks to protect against CUS-induced brain damage.

RESUMEN: El estrés crónico es un factor de riesgo para el deterioro de la memoria y las anomalías neurológicas tanto en humanos como en animales. Intentamos investigar el alcance de lesión del tejido cerebral; (ii) estrés nitrosativo y oxidativo en homogeneizados de tejido cerebral; (iii) biomarcadores apoptóticos y de supervivencia en homogeneizados de tejido cerebral; y (iv) inmovilidad y habilidades de escalada, inducidas durante un período de tres semanas por estrés crónico impredecible (ECI). Se dejaron sin tratamiento (grupo control) ratas Wistar, o se expusieron a una variedad de factores estresantes impredecibles diariamente antes de ser sacrificadas después de 3 semanas (grupo modelo). Se realizó una evaluación del comportamiento similar a la depresión y luego se sacrificaron los animales y se tiñeron los tejidos cerebrales con tinción histológica básica y se examinaron con microscopía óptica. Además, se prepararon homogeneizados de tejido cerebral y se analizaron los siguientes parámetros; óxido nítrico sintasa inducible (iNOS), malondialdehído (MDA), superóxido dismutasa (SOD), caspasa- 3 y linfoma de células B 2 (Bcl-2). Las imágenes histológicas mostraron que el CUS indujo un daño profundo en la corteza cerebral como lo demuestra el daño neuronal severo con células encogidas, núcleos atróficos alterados, vacuolación perineuronal y células gliales inflamadas. ECI también indujo significativamente (p <0,05) iNOS, MDA y caspase-3, mientras que los niveles de tejido cerebral SOD y Bcl-2 fueron inhibidos por ECI. Además, los datos del comportamiento similar a la de- presión, la prueba de natación forzada mostró un aumento significativo (p <0,05) en la inmovilidad animal y una disminución en la capacidad de escalada en el grupo modelo de ratas. Por lo tanto, aquí demostramos un modelo confiable de daño cerebral crónico en rata inducido por el estrés, que se puede utilizar para investigar medicamentos o agentes beneficiosos usados durante un período de tres semanas para proteger el daño cerebral inducido por ECI.

Suppression of type 2 diabetes mellitus-induced aortic ultrastructural alterations in rats by insulin: an association of vascular injury biomarkers.

Diabetes represents a major public health problem and an estimated 70% of people with diabetes die of cardiovascular complications. The protective effect of insulin treatment against ultrastructural damage to the tunica intima and tunica media of the aorta induced by type 2 diabetes mellitus (T2DM) has not been investigated before using transmission electron microscopy (TEM). Therefore, we induced T2DM in rats using high fat diet and streptozotocin (50 mg/kg) and administered insulin daily by i.v injection for 8 weeks to the treatment group. Whereas, the T2DM control group were left untreated for the duration of the experiment. A comparison was also made between the effect of insulin on aortic tissue and the blood level of biomarkers of vascular injury, inflammation, and oxidative stress. T2DM induced profound ultrastructural damage to the aortic endothelium and vascular smooth muscle cells, which were substantially protected with insulin. Furthermore, insulin returned blood sugar to a control level and significantly (p < .05) inhibited diabetic up-regulation of endothelial and leukocyte intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion protein 1 (VCAM-1), endothelial cell adhesion molecules, P-selectin and E-selectin, tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), and malondialdehyde (MDA). Furthermore, insulin augmented the blood level of the anti-oxidant enzyme superoxide dismutase (SOD). We conclude that in a rat model of T2DM, insulin treatment substantially reduces aortic injury secondary to T2DM for a period of 8 weeks, possibly due to the inhibition of hyperglycemia, vascular activation, inflammation, and oxidative stress.

Minocycline protects against acrylamide-induced neurotoxicity and testicular damage in Sprague-Dawley rats.

This study investigated the protective effects of minocycline against acrylamide (ACR)-induced neurotoxicity and testicular damage in Sprague-Dawley rats. Forty rats were divided into five groups (eight rats each). Group I received saline (0.5 mL/rat) daily for 10 days and served as the untreated control group. Group II received ACR (30 mg/kg body weight (b.w.)) daily for 10 days. Group III received ACR (30 mg/kg b.w.) daily for 10 days and subsequently minocycline (60 mg/kg b.w.) for five days. Group IV received ACR (30 mg/kg b.w.) daily for 10 days followed by saline for five days and served as the control group for the ACR-minocycline-treated group. Group V received minocycline (60 mg/kg b.w.) for five days. All treatments were administered orally. Rats in group I and V showed normal locomotor behavior and normal histology of the brain and testes. Administration of ACR (Group II and IV) resulted in weight loss and gait abnormalities. Furthermore, neuronal degeneration in the hippocampus and cerebellum and degeneration of the seminiferous tubular epithelium with formation of spermatid giant cells were observed. Ultrastructurally, ACR specifically damaged spermatogonia and spermatocytes. Acrylamide was also seen to cause a significant increase of malondialdehyde levels in the brain and testes. Treatment of ACR-administered rats with minocycline (Group III) significantly alleviated the loss of body weight and improved locomotor function. Minocycline also ameliorated neuronal degeneration and seminiferous tubular damage and decreased malondialdehyde concentrations. In conclusion, minocycline protects against neurotoxic effects of acrylamide and seminiferous tubular damage. Decreasing lipid peroxidation by minocycline might play a role in such protection.

Exercise and Stevia Rebaudiana (R) Extracts Attenuate Diabetic Cardiomyopathy in Type 2 Diabetic Rats: Possible Underlying Mechanisms.

BACKGROUND AND AIMS: In the current work, we studied the effects of exercise and stevia rebaudiana (R) extracts on diabetic cardiomyopathy (DCM) in type 2 diabetic rats and their possible underlying mechanisms. METHODS: Thirty-two male Sprague Dawley rats were randomly allocated into 4 equal groups; a) normal control group, b) DM group, type 2 diabetic rats received 2 ml oral saline daily for 4 weeks, c) DM+ Exercise, type 2 diabetic rats were treated with exercise for 4 weeks and d) DM+ stevia R extracts: type 2 diabetic rats received methanolic stevia R extracts. By the end of the experiment, serum blood glucose, HOMA-IR, insulin and cardiac enzymes (LDH, CK-MB), cardiac histopathology, oxidative stress markers (MDA, GSH and CAT), myocardial fibrosis by Masson trichrome, the expression of p53, caspase-3, α-SMA and tyrosine hydroxylase (TH) by immunostaining in myocardial tissues were measured. RESULTS: T2DM caused a significant increase in blood glucose, HOMA-IR index, serum CK-MB and LDH, myocardial damage and fibrosis, myocardial MDA, myocardial α-SMA, p53, caspase-3, Nrf2 and TH density with a significant decrease in serum insulin and myocardial GSH and CAT (p< 0.05). On the other hand, treatment with either exercise or stevia R extracts significantly improved all studied parameters (p< 0.05). Moreover, the effects of stevia R was more significant than exercise (p< 0.05). CONCLUSION: Both exercise and methanolic stevia R extracts showed cardioprotective effects against DCM and Stevia R offered more cardioprotective than exercise. This cardioprotective effect of these lines of treatment might be due to attenuation of oxidative stress, apoptosis, sympathetic nerve density and fibrosis and upregulation of the antioxidant transcription factor, Nrf2.

Vanadium inhibits Type 2 diabetes mellitus-induced aortic ultrastructural alterations associated with the Inhibition of dyslipidemia and biomarkers of inflammation in rats / El vanadio inhibe las alteraciones ultraestructurales aórticas inducidas por la diabetes mellitus Tipo 2 asociadas con la inhibición de la dislipidemia y los biomarcadores de inflamación en ratas

The potential inhibitory effect of the insulin mimicking agent, vanadium on type 2 diabetes mellitus (T2DM)induced alterations to the aorta ultrastructure associated with the suppression of dyslipedima and biomarkers of inflammation has not been investigated before. Therefore, we tested whether vanadium can protect against aortic injury induced secondary to T2DM possibly via the inhibition of blood lipid and inflammatory biomarkers. T2DM was induced in rats by a high-fat diet and streptozotocin (50 mg/ kg), and the treatment group started vanadium treatment five days post diabetic induction and continued until being sacrificed at week 10. Using light and electron microscopy examinations, we observed in the model group substantial damage to the aorta tissue such as damaged endothelium, degenerative cellular changes with vacuolated cytoplasm and thickened internal elastic lamina that were substantially ameliorated by vanadium. Administration of vanadium to diabetic rats also significantly (p<0.05) reduced blood levels of glucose, hyperlipidemia and biomarkers of inflammation (TNF-a, IL-6). We conclude that vanadium protects against T2DM-induced aortic ultrastructural damage in rats, which is associated with the inhibition of blood sugar and lipid and inflammatory biomarkers.

El potencial efecto inhibidor del agente imitador de la insulina, el vanadio en las alteraciones inducidas por la diabetes mellitus tipo 2 (DM2) en la ultraestructura de la aorta, asociada con la supresión de dislipidemia y los biomarcadores de inflamación no se ha investigado anteriormente. El objetivo fue estudiar las propiedades del vanadio para proteger contra la lesión aórtica inducida a la DM2, a través de la inhibición de los lípidos sanguíneos y los biomarcadores inflamatorios. La DM2 fue inducida en ratas con una dieta alta en grasas y estreptozotocina (50 mg / kg), y el grupo de tratamiento fue sometido a un régimen continuo con vanadio, cinco días después de la inducción diabética hasta ser sacrificadas en la semana 10. Se utilizaron exámenes de luz y microscopía electrónica en el grupo modelo y se observó un daño sustancial al tejido de la aorta, como también en el endotelio; los cambios celulares degenerativos con citoplasma vacuolado y lámina elástica interna engrosada mejoró sustancialmente con vanadio. La administración de vanadio a ratas diabéticas también redujo significativamente (p <0,05) los niveles sanguíneos de la glucosa, hiperlipidemia y los biomarcadores de inflamación (TNFa, IL-6). En conclusión, el vanadio protege contra el daño ultraestructural aórtico inducido por T2DM en ratas, que es asociado con la inhibición del azúcar en la sangre y los biomarcadores de lípidos y de inflamatorios.

Metformin suppresses aortic ultrastrucural damage and hypertension induced by diabetes: a potential role of advanced glycation end products.

Cardiovascular disease secondary to diabetes represents a significant challenge to the health community. The advanced glycation end products (AGEs) play an important role in diabetes-mediated vascular injury. We tested whether metformin can suppress aortic AGEs production and protect against aortic injuries (aortopathy) and hypertension in streptozotocin-induced type 2 diabetes mellitus (T2DM) animal model. T2DM was induced in rats two weeks after being fed on a high carbohydrate and fat diet (HCFD), and continued on a HCFD until being sacrificed at week 12 (model group). The protective group was put on metformin two weeks before diabetic induction and continued on metformin and HCFD until the end of the experiment, at week 12. Using electron microscopy examinations, we observed in the model group substantial damage to the ultrastructure of aortic endothelial and vascular smooth muscle layers as demonstrated by markedly distorted vacuolated endothelial and vascular smooth muscle cells with pyknotic nuclei detached from the underlying basement membrane, which were protected by metformin. Also, metformin significantly (p < .05) decreased both systolic and diastolic blood pressure, aortic levels of AGEs, and blood levels of oxidative stress and inflammatory biomarkers. We conclude that metformin protects against T2DM-induced aortopathy and hypertension, possibly via the inhibition of AGEs, inflammation, and oxidative stress.

Vitamin E ameliorates alterations to the articular cartilage of knee joints induced by monoiodoacetate and diabetes mellitus in rats.

We recently reported an animal model of osteoarthritis (OA) induced by a combination of the chondrocyte glycolysis inhibitor, monoiodoacetate (MIA) and the agent that induces diabetes mellitus, streptozotocin (STZ). Here we investigated the potential protective effect of the antioxidant and anti-inflammatory agent, vitamin E against MIA+STZ-induced OA. Therefore, rats were either injected once with MIA (2 mg/50 µL) + 65 mg/kg STZ before being sacrificed after 8 weeks (model group) or were treated immediately after MIA+STZ injections with vitamin E (600 mg/kg; thrice a week) before being sacrificed after 8 weeks (treatment group). Using scanning and transmission electron microscopy examinations, we observed in the model group a substantial damage to the articular cartilage of the knee joint as demonstrated by the destruction of the chondrocytes, territorial matrix, disrupted lacunae, collagen fibers, and profound chondrocyte ultrastructural alterations such as degenerated chondrocyte, irregular cytoplasmic membrane, damaged mitochondria and rough endoplasmic reticulum, vacuolated cytoplasm, presence of lipid droplets and different sizes of lysosomes, which were substantially but not completely protected by vitamin E. H&E stained sections of knee joint articular cartilage showed that MIA+STZ induced damage to the chondrocyte and territorial matrix. Vitamin E also significantly (p < .05) inhibited MIA+STZ-induced blood levels of the inflammatory biomarkers, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) that are known to be modulated in OA and diabetes. We conclude that vitamin E protects against MIA+STZ-induced knee joints injuries in rats, which is associated with the inhibition of biomarkers of inflammation.

Swim exercise inhibits hemostatic abnormalities in a rat model of obesity and insulin resistance.

BACKGROUND: We sought to determine whether swim exercise can inhibit high carbohydrate and fat diet (HCFD)-induced biomarkers of coagulation and thrombosis. MATERIAL AND METHODS: Rats were either fed with HCFD (model group) or a standard laboratory chow (control group) for 15 weeks. Swim exercise-'treated' rats started swim exercise training from the 11th week until being sacrificed, on Week 15. RESULTS: HCFD caused a significant increase in blood glucose, insulin resistance (HOMA-IR), lipidemia, and inflammatory biomarkers. In addition, HCFD significantly modulated coagulation and thrombosis biomarkers; fibrinogen, plasminogen activator inhibitor-1, von Willebrand factor, prothrombin time, activated partial thromboplastin time, blood clotting and bleeding time, and ADP-induced platelet aggregation that was effectively inhibited by swimming exercises. CONCLUSIONS: We demonstrate that in an animal model of obesity and insulin resistance, there is a significant change in hemostasis, which is ameliorated by swim exercise.

Ghrelin prevents cardiac cell apoptosis during cardiac remodelling post experimentally induced myocardial infarction in rats via activation of Raf-MEK1/2-ERK1/2 signalling.

CONTEXT: Mechanisms by which ghrelin affords its cardioprotection in mammals remained unclear. OBJECTIVE: To examine if ghrelin confers cardio-protection during cardiac remodelling post-MI by modulating the RAF-1-MEK1/2-ERK1/2 signalling pathway. MATERIALS AND METHODS: Rats were divided into control, sham, sham + ghrelin, myocardial infarction (MI), and MI + ghrelin groups. Ghrelin (100 µg/kg) was administered for 21 days, starting one-day post-MI. RESULTS: Ghrelin enhanced cardiac contractility and the activities of antioxidant enzymes, lowered serum levels of enzyme markers of cardiac dysfunction, and lowered inflammatory mediator levels. Ghrelin increased levels of phospho-Raf-1 (Ser338), phospho-MEK1/2 (Ser217/221), phospho-ERK1/2 (Thr202/Tyr204), and of their downstream target p-BAD (Ser112) and inhibited the cleavage of caspase-3. Concomitantly, ghrelin prevented the increases in the levels of fibrotic markers, including α-smooth muscle actin (α-SMA), metalloproteinase-9 (MPP-9), and type III collagen. CONCLUSION: Post-MI in rats, ghrelin stimulated Raf-1-MEK1/2-ERK1/2-BAD signalling in the LV infarct areas, accounting for its anti-apoptotic effect, enhancing cardiac function, and inhibiting cardiac fibrosis during cardiac remodelling.

Ultrastructural morphological alterations during hyperoxia exposure in relation to glutathione peroxidase activity and free radicals productions in the mitochondria of the cortical brain / Alteraciones morfológicas ultraestructurales durante la exposición a la hiperoxia en relación con la actividad de la glutatión peroxidasa y la producción de radicales libres en las mitocondrias de la corteza cerebral

Exposure to normobaric hyperoxia (NH) is known to increase the production of reactive oxygen species (ROS) by mitochondria. The present study was designed to examine mitochondrial ultrastructure morphological changes in the cortical brainin relation to glutathione peroxidase (GPX) activity and free radicals (FR) productions in brain tissue during hyperoxia exposure. The experimental groups were exposed to NH for 24 and 48 h continuously. Following the exposure periods, animals were sacrificed and cortical tissues were divided randomly into two parts; the first part was processed for the ultrastructural examination and the second was homogenized for GPX and FR determinations. Analysis of variance (ANOVA) showed that the main effects of O2 exposure periods were significant (p<0.05) for GPX and FR. Pair-wise means comparisons showed that NH elevated the average (+SE) GPX activity significantly (p<0.05) from the baseline control value of 5670.99+556.34 to13748.42+283.04 and 15134.19+1529.26 U/L with increasing length of NH exposure period from 24 to 48 h, respectively. Similarly, FR production was increased significantly (p<0.05) to 169.73+10.31 and 185.33+21.87, above baseline control of 105.27+5.25 Unit. Ultrastructure examination showed that O2 breathing for 48 h resulted in giant and swelled mitochondria associated with diluted inner membrane and damaged cristae. These mitochondria pathological alterations were associated with damages of myelin, axonal and cellular organelles. Normobaric-hyperoxia inducts mitochondria oxidative stress (MOS) and the subsequent rise of ROS causes variety of ultrastructure morphological pathological alterations in the organelles of cortical brain cells.

Se sabe que la exposición a la hiperoxia normobárica (HN) aumenta la producción de especies reactivas de oxígeno (ERO) por parte de las mitocondrias. El estudio se diseñó para examinar los cambios morfológicos de la ultraestructura mitocondrial en la corteza cerebral con la actividad de la glutatión peroxidasa (GPX) y la producción de radicales libres (RL) en el tejido cerebral durante la exposición a la hiperoxia. Los grupos experimentales fueron expuestos a HN durante 24 y 48 h continuamente. Tras los períodos de exposición, los animales se sacrificaron y los tejidos corticales se dividieron aleatoriamente en dos partes; la primera parte se procesó para el examen ultraestructural y la segunda se homogeneizó para las determinaciones de GPX y RL. El análisis de varianza (ANOVA) mostró que los efectos principales de los períodos de exposición al O2 fueron significativos (p <0,05) para GPX y RL. Las comparaciones de medias por pares mostraron que la HN elevó la actividad promedio de GPX (+ SE) significativamente (p <0,05) desde el valor de control de línea base de 5670,99 + 556,34 a 13748,42 + 283,04 y 15134,19 + 1529,26 U / L con una mayor duración del período de exposición a HN de 24 a 48 h, respectivamente. De manera similar, la producción de RL se incrementó significativamente (p <0,05) a 169,73 + 10,31 y 185,33 + 21,87, por encima del control de referencia de 105,27 + 5,25 unidades. El examen de la ultraestructura mostró que la respiración de O2 durante 48 h dio lugar a mitocondrias gigantes e hinchadas asociadas con la membrana interna diluida y las crestas dañadas. Estas alteraciones patológicas de las mitocondrias se asociaron con daños de mielina, axones y organelos celulares. La hiperoxia normobárica induce el estrés oxidativo mitocondrial (MOS) y el posterior aumento de las ERO provoca una variedad de alteraciones patológicas y morfológicas en los organelos de las células cerebrales corticales.

Metformin pretreatment ameliorates diabetic nephropathy induced by a combination of high fat diet and streptozotocin in rats / El pretratamiento con metformina mejora la nefropatía diabética inducida por una combinación de dieta alta en grasas y estreptozotocina en ratas

Kidney injury secondary to diabetes is the most common cause of kidney failure. We sought to determine whether pretreatment with the insulin-sensitizing drug metformin prior to the induction of diabetes can protect the kidney against the development of diabetic nephropathy (DN) induced by a combination of a high-fat diet and streptozotocin. Rats were either injected with vehicle (control group) or with a single injection of streptozotocin (STZ) (50 mg/kg) two weeks after being fed on a high-fat diet (HFD) (model group) and continued on HFD until being sacrificed 10 weeks post diabetic induction. The protective group that also fed on a HFD for 12 weeks was put on metformin (200 mg/kg/day) two weeks before STZ injection and continued on metformin until the sacrifice day. Harvested kidney tissues were examined by light microscopy after staining with hematoxylin and eosin (H&E) and periodic acid Schiff (PAS). Blood samples were assayed for sugar, urea, creatinine, and biomarkers of inflammation. Compared to a normal tissue histology in the control group, there was a profound damage to the kidney in the model group as demonstrated by markedly dilated capsular space, increased mesangial matrix expansion, congested blood vessels, and many tubular epithelial cells showing small pyknotic nuclei and vacuolated cytoplasm, which were significantly but not completely protected by metformin. Our findings also show that metformin significantly inhibited the inflammatory biomarkers, tumor necrosis factor-alpha (TNF-α) and C-reactive protein (CRP) induced by diabetes and HFD as well as significantly inhibiting blood sugar, urea, and creatinine. However, the levels of TNF-α, CRP, glucose, and creatinine in the metformin-treated group was still significant to the control group. Thus, we demonstrated an efficient but not complete protection by metformin pretreatment against DN induced by a combination of HFD and streptozotocin in rats.

La lesión renal secundaria a la diabetes es la causa más común de insuficiencia renal. Intentamos determinar si el pre tratamiento con metformina, un fármaco sensibilizante a la insulina antes de la inducción de diabetes, puede proteger al riñón del desarrollo de la nefropatía diabética (DN) inducida por una combinación de una dieta alta en grasas y estreptozotocina. Las ratas fueron inyectadas con el medio (grupo de control) o con una inyección única de estreptozotocina (STZ) (50 mg / kg) dos semanas después de ser alimentadas con una dieta alta en grasas (HFD) (grupo modelo) y continuaron en HFD hasta ser sacrificadas 10 semanas después de la inducción diabética. El grupo protector que también se alimentó con un HFD durante 12 semanas recibió metformina (200 mg / kg / día) dos semanas antes de la inyección de STZ y continuó con metformina hasta el día en que fueron sacrificadas. Las muestras de riñón se examinaron mediante microscopía óptica después de la tinción con Hematoxilina y Eosina y ácido peryódico de Schiff (PAS). Las muestras de sangre se analizaron para determinar niveles de azúcar, urea, creatinina y biomarcadores de inflamación. Comparado con una histología tisular normal en el grupo control, hubo un daño profundo al riñón en el grupo modelo como lo demuestra el espacio capsular marcadamente dilatado, el aumento de la expansión de la matriz mesangial, los vasos sanguíneos congestionados y muchas células epiteliales tubulares que muestran pequeños núcleos picnóticos y citoplasma vacuolado, que fueron significativamente pero no completamente protegidos por la metformina. Nuestros hallazgos también muestran que la metformina inhibe significativamente los biomarcadores inflamatorios, el factor de necrosis tumoral alfa (TNF-a) y la proteína C reactiva (PCR) inducida por diabetes y DFH, e inhibe significativamente el azúcar en sangre, la urea y la creatinina. Sin embargo, los niveles de TNF-a, CRP, glucosa y creatinina en el grupo tratado con metformina todavía eran significativos para el grupo de control. Por lo tanto, demostramos una protección eficiente pero no completa mediante pretratamiento con metformina contra DN inducida por una combinación de HFD y estreptozotocina en ratas.

Natural Hypoxia is Not a Limiting Factor in Evaluating the Novel Arylidene Derivative MLT-401 Against an In Vitro Colorectal Cancer Model.

BACKGROUND/AIMS: Cancer cells in vivo develop resistance to many anti-tumor drugs. One known factor to influence such drug resistance is hypoxia, which is an important component of the tumor microenvironment. Standard cancer lines mostly do not exhibit a cellular hypoxic microenvironment and there is a paucity of information on the efficacy of lead molecules in both cellular- and environment-induced hypoxic conditions. Therefore, in the present study, we have evaluated the efficacy of the arylidene derivative MLT-401, a lead molecule showing activity against colorectal cancer model using the HCT 116 cell line and CCD-80-C control cells in normoxic and natural (marginal) hypoxic conditions, which is usually observed in high-altitude regions. METHODS: The efficacy of MLT-401 on HCT 116 and CCD-80-C cells were tested in both normoxia and marginal hypoxia conditions. MTT assay was used to evaluate cell proliferation, Annexin V binding assay for apoptotic cell quantification and PI staining for cell cycle were done by flow cytometry. Induction of pro-apoptotic marker BAX and anti-apoptotic Bcl-2 were assessed by western blot. Bcl-2/BAX ratio was calculated based on protein expression by western blotting and bands were quantified by Image J software. RESULTS: Analysis of cell proliferation showed an average 10-fold reduction in the inhibition of HCT 116 cells in hypoxic conditions with approximately 500 nM MLT-401, while there was no significant change noted in marginal hypoxic conditions. A proportionate increase in the number of apoptotic cells and large M4 fraction of 10.5% and 26.7% of HCT116 against 6.3% of control cells in cell cycle assessment with MLT-401 concentrations ranging from 250 to 500 nM respectively clearly demonstrated anti-cancer activity. A Bcl-2/BAX ratio of < 1 showed that the induction of apoptosis was the gross mechanism underlying the inhibition of HCT 116 cells by MLT-401. CONCLUSION: Collectively, these results show MLT-401 as an effective anti-colorectal cancer lead molecule irrespective of normoxia or natural hypoxia.

Swim exercise training ameliorates hepatocyte ultrastructural alterations in rats fed on a high fat and sugar diet.

Excessive consumption of carbohydrate and fat increases the risk of liver disease. We hypothesized that swim exercise can protect hepatocytes from ultra-structural damage induced by high cholesterol and fructose diets (HCFD). Rats were either fed with HCFD (model group) or a standard laboratory chow (control group) for 15 weeks before being sacrificed. Swim exercise trained rats started the treatment from the 11th week until the sacrifice day, end of week 15. Blood samples were assayed for biomarkers of liver injury and adiponectin. The harvested liver tissues were examined using transmission electron microscopy (TEM). TEM images revealed substantial damage and accumulation of lipid droplets (steatosis) in the hepatocytes of the model group that was inhibited by swim exercise. In addition, HCFD significantly (p < 0.0005) increased insulin resistance index (HOMA-IR), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), which were effectively (p < 0.02) decreased by a swim exercise to levels comparable to control group. Whereas, swim exercise increased adiponectin levels in HCFD group (p < 0.03). These results show that HCFD-induced hepatic injury is ameliorated by swim training exercise possibly via restoration of a normal blood sugar and lipid, induction of adiponectin and inhibition of inflammatory, and liver injury biomarkers.

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.