Comparative cardioprotective effects of carvedilol versus atenolol in a rat model of cardiorenal syndrome type 4.

The incidence of chronic kidney disease is escalating; cardiorenal syndrome (CRS) type 4 is gaining a major health concern causing significant morbidity and mortality, putting major burdens on the healthcare system. This study was designed to compare the cardioprotective effects of carvedilol versus atenolol against CRS type 4 induced by subtotal 5/6 nephrectomy in rats and to explore the underlying mechanisms. Immediately after surgery, carvedilol (20 mg/kg/day) or atenolol (20 mg/kg/day) was added to drinking water for 10 weeks. Carvedilol was more effective than atenolol in improving kidney functions, decreasing elevated blood pressures, attenuating cardiac hypertrophy, reducing serum brain natriuretic peptide, and diminished cardiac fibrous tissue deposition. However, carvedilol was equivalent to atenolol in modulating ß1-adrenergic receptors (ß1ARs) and cardiac diacylglycerol (DAG) signaling, but carvedilol was superior in modulating ß-arrestin2, phosphatidyl inositol 4,5 bisphosphates (PIP2), and caspase 3 levels. Carvedilol has superior cardioprotective effects than atenolol in a rat model of CRS type 4. These protective effects are mediated through modulating cardiac ß1ARs/ß-arrestin2/PIP2/DAG as well as abating cardiac apoptotic signaling pathways (caspase3/pS473 protein kinase B (Akt)).

Comparison between the effect of human Wharton's jelly-derived mesenchymal stem cells and levetiracetam on brain infarcts in rats.

BACKGROUND: Stroke represents one of the major causes of death worldwide. Neuroprotection remains an important goal of stroke therapy. Stem cell therapeutic effect is attributed to the neuroprotective effect and the regulation of the oxidant stress. Levetiracetam (LEV), a second-generation antiepileptic drug, was reported to confer neuronal protection after cerebral ischemia reperfusion. AIM: To investigate the effect of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) and LEV on the size of brain infarcts, the histological structure, the neurotrophic, and the antioxidant gene expression in middle cerebral artery occlusion in rats. METHOD: The rats were divided into five equal groups of 12 rats each as follows. Sham control group: received phosphate-buffered saline (PBS); ischemia/reperfusion (I/R) group: received PBS before ligation; stem cell-treated group: the animal received MSCs before ligation; LEV-treated group: the animal received LEV before occlusion; combined group: the animals received both MSCs and LEV before occlusion. Hematoxylin and eosin staining was performed to study the histological structure of the brain. Real-time polymerase chain reaction (RT-PCR) was performed to assess gene expression. RESULTS: Both MSCs and LEV improved memory and learning in the treated groups compared with I/R group. Significant reduction of the infarct size in WJ-MSC- or LEV-treated groups when compared with untreated ones was found. By RT-PCR, a significant decrease of the expression values of glial-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), phosphatidylethanolamine binding protein 1 (PEBP1), and copper-zinc SOD (Cu/ZnSOD) genes and a significant increase of pro-oxidant iNOS gene in the I/R rats compared with the sham group was detected. There was a significant increase in the expression values of GDNF, BDNF, PEBP1, and Cu/ZnSOD genes in both treated groups when compared with the I/R group. Rats treated with WJ-MSCs showed better results than rats treated with LEV. Finally, the combined use of LEV and WJ-MSCs was the most effective regimen as regard infarction volume and functional learning and memory tests. CONCLUSION: In the brain ischemia model, combined WJ-MSCs and LEV have demonstrated striking protective effects in brain infarction by the modulation of the oxidant status and neuroprotective effect.

Hesperidin protects against stress induced gastric ulcer through regulation of peroxisome proliferator activator receptor gamma in diabetic rats.

Stress induced gastric ulcer is a serious health problem in diabetic patients. Some studies reported that hesperidin (HDN), a citrus bioflavonoid, can bind to and stimulate peroxisome proliferator-activator receptor-gamma (PPAR-γ) which may mediate its antidiabetic, anti-inflammatory and anti-oxidant effects. This work aims to study the possible protective effect of HDN against stress induced gastric ulcer in diabetic rats as well as the possible involvement of PPARγ in this effect. Type 2 diabetes was induced using streptozotocin and nicotinamide. Diabetic rats received either HDN (100 mg/kg/day, orally) & omeprazole (20 mg/kg/day, orally) or HDN (100 mg/kg/day, orally) + GW9662, PPARγ antagonist, (1 mg/kg/day, i.p.) for 8 weeks then acute gastric injury was induced by cold restraint stress technique. Glycemic controls and gastroprotective effects were evaluated by measuring serum levels of glucose and insulin, gastric free and total acidity and gastric ulcer indices. Histopathological examination of gastric mucosa was also performed. To determine the underlying mechanism of action, gastric mucosal expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), hemeoxygenase-1 (HO-1), cluster of differentiation 45 (CD45), cyclooxygenase-2 (COX-2), nuclear factor kappa B (NFκB) and inducible nitric oxide synthase (iNOS), gastric contents of reduced glutathione (GSH), malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α) and nitric oxide (NO); as well as superoxide dismutase (SOD) and catalase activities were measured. HDN significantly improved glycemic level; it also reduced gastric acidity and gastric ulcer index and histopathological changes comparable to that produced by omeprazole. Moreover, HDN reduced lipid peroxidation and inflammatory markers levels and enhanced antioxidant capacity. The use of GW9662 significantly abrogated the gastric protective effect of HDN as well as reduced the antioxidant and anti-inflammatory effects. Our work showed, for the first time that, HDN has promising protective effect against stress induced gastric ulcer in diabetic rats through activation of PPARγ.

Sildenafil protects against bile duct ligation induced hepatic fibrosis in rats: Potential role for silent information regulator 1 (SIRT1).

Hepatic fibrosis is a potential health problem that may end with life-threatening cirrhosis and primary liver cancer. Recent studies point out to the protective effects of silent information regulator1 (SIRT1), against different models of organs fibrosis. This work aimed to investigate the possible protective effect of sildenafil (SIRT1 activator) against hepatic fibrosis induced by bile duct ligation (BDL). Firstly, three different doses of sildenafil (5, 10, 20mg/kg/day) were investigated; to detect the most protective one against BDL induced liver dysfunction and hepatic fibrosis. The most protective dose is then used; to study its effect on BDL induced SIRT1 downregulation, imbalance of oxidant/antioxidant status, increased inflammatory cytokines and fibrosis. Sildenafil (20mg/kg/day) was the most protective one, it caused upregulation of SIRT1, reduction of hepatic malondialdehyde (MDA) content, increase in expression of nuclear factor erythroid 2-related factor 2 (Nrf2), hemeoxygenease (HO)-1, reduced glutathione (GSH) content and superoxide dismutase (SOD) activity. Hepatic content of tumor necrosis factor-α (TNF-α) and nuclear factor κB (NFκB) expression & content displayed significant reductions with sildenafil treatment, Furthermore, sildenafil caused marked reductions of transforming growth factor (TGF)-ß content, expression of plasminogen activator inhibitor-1 (PAI-1), matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), α-smooth muscle actin (α-SMA), fibronectin, collagen I (α1) and hydroxyproline content. However, sildenafil protective effects were significantly reduced by co-administration of EX527 (SIRT1 inhibitor). Our work showed, for the first time that, sildenafil has promising protective effects against BDL induced liver dysfunction and hepatic fibrosis. These effects may be, in part, mediated by up regulation of SIRT1.

Renoprotective effect of Hypericum perforatum against diabetic nephropathy in rats: Insights in the underlying mechanisms.

Oxidative stress and inflammation play a key role in the initiation and progression of diabetic nephropathy (DN). The present study aimed to investigate the possible protective effect of hypericum perforatum (HP) against DN. Rats were allocated into six groups: control, received normal saline; diabetic untreated (DM), received single dose of streptozotocin (STZ) after injection of nicotinamide (NA); gliclazide, received STZ,NA + gliclazide (10 mg/kg); DM + HP50, DM + HP100, DM + HP200, received STZ,NA and HP 50, 100, 200 mg/kg, respectively. Gliclazide and HP were administered daily via gavage for 8 weeks. Serum glucose, insulin, kidney function and histopathological picture were assessed. Furthermore, oxidative/nitrosative stress, inflammatory cytokines, apoptotic and fibrotic markers were measured. Diabetic untreated group showed increase in serum glucose, urea, creatinine with albuminurea. Renal expression of protein for nuclear factor kappa-B (NF-кB), renal expression of inducible nitric oxide synthase (iNOS), cyclooxygenase II (COXII), collagen IV, fibronectin were elevated. Malondialdehyde (MDA), nitric oxide (NO), tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), intracellular adhesion molecule (ICAM-1), monocellular chemoattractant protein-1 (MCP-1), tumour growth factor- ß (TGF-ß), caspase-3 and cytochrome c contents were also increased consequently with decline of serum insulin, expression of peroxisome proliferator-activated receptor (PPARγ), renal reduced glutathione (GSH) content and superoxide dismutase (SOD) activity. Treatment with either gliclazide or HP mitigated the deleterious effects of STZ on the tested parameters. These findings indicate for the first time that HP may have a renoprotective effect against DN through reduction of oxidative/nitrosative stress, enhancement of antioxidant defense mechanisms, decline of inflammatory cytokines, antifibrotic, antiapoptotic and blood glucose lowering properties.

Comparing the effects of MSCs and CD34+ cell therapy in a rat model of myocardial infarction.

Stem cell therapy is considered as a promising approach in the treatment of myocardial infarction (MI). This study was designed as a comparison of human umbilical cord blood (HUCB)-derived CD34+ and HUCB-derived MSCs for the repair of cardiac tissue by induction of the angiogenesis. Forty-eight male rats were randomized into four groups: sham-operated group, MI group, MSCs-treated group, and CD34+ cells-treated group. After 4 weeks, the rats were sacrificed. All sections from left ventricles of all groups were subjected to hematoxylin & eosin, Masson's trichrome, and immunohistochemical stains (CD133, CD44, and α-smooth muscle actin). RNA was extracted for gene expression of the angiogenic markers. A significant reduction of the infarct size and the amplitude of T-wave in the CD34+ cells-treated group when compared with the MSCs-treated group were determined. Histologically, the MI group showed scar tissue, congested blood capillaries around the infarcted area, some necrotic cells, and inflammatory cells. Administration of either MSCs or CD34+ cells had a therapeutic potential to induce regenerative changes in the myocardium with better results in CD34+cells-treated group. Quantitative RT-PCR analysis revealed a significant increase in the expression of vascular endothelial growth factor (VEGF), VEGFR-2, Ang-1, and Tie-2 and a significant decreased expression of Ang-2 in stem cells transplanted groups when compared with the noncell transplanted hearts. A significant increase of VEGF, VEGFR-2, Ang-1, and Tie-2 expression in the group receiving CD34+ cells than those receiving MSCs was found. Finally, there was an upregulation of both human VEGF and human hypoxia-inducible factor 1α in the infarcted hearts treated by CD34+ cells than that treated by MSCs. We first revealed a superior efficacy of CD34+ cells when compared with MSCs in induction of regenerative changes in the MI model. Both cell therapies may repair the damaged heart tissue primarily by secretion of proangiogenic factors that induce the angiogenesis and activate the angiogenesis signaling pathway. © 2016 IUBMB Life, 68(5):343-354, 2016.

Anti-oxidative and anti-apoptotic roles of spermatogonial stem cells in reversing cisplatin-induced testicular toxicity.

BACKGROUND AIMS: Because of reproductive toxic effects of chemotherapy, researchers have taken some techniques to preserve fertility potential. The present study was designed to point out the potential role of spermatogonial stem cell (SSC) therapy in reversing cisplatin (CP)-induced testicular toxicity and restore the spermatogenesis. METHODS: Sixty rats were randomly divided into three groups: group 1, control group; group 2, rats received CP in a dose of 7 mg/kg/day for 5 consecutive days; group 3, CP was injected at 7 mg/kg per day for 5 consecutive days, and, on the 6th day of the experiment, rats were treated with SSC. Forty days after receiving the last dose of CP, rats were euthanized under anesthesia; testes were collected, and gene expression using real-time polymerase chain reaction for P53, Bax, caspase 9 and cytochrome c, testicular histological findings and oxidative status were determined. RESULTS: Administration of cisplatin caused significant increases in malondialdehyde levels, Bax and caspase 9 genes expression levels concomitant with significant decreases in anti-oxidant enzyme activities, p53 and cytochrome c gene expression levels, along with some histopathological lesions in testicular tissue. SCC attenuated the disturbance in oxidant/anti-oxidant status and testicular apoptosis; this is associated with improvements in the histopathological view of the testicular tissue. CONCLUSIONS: The current study highlights evidence that the SCC has anti-oxidative and anti-apoptotic properties that could reverse CP-induced testicular toxicity, in addition to their role in spermatogenesis.

Mesenchymal stromal cell injection protects against oxidative stress in Escherichia coli-induced acute lung injury in mice.

BACKGROUND AIMS: Stem cells may be a promising therapy for acute respiratory distress syndrome. Recent in vivo and in vitro studies suggested that the mesenchymal stromal cells (MSCs) have anti-oxidative stress properties. We hypothesized that intravenous injection of bone marrow-derived mesenchymal stem cells (MSCs) could attenuate Escherichia coli-induced acute lung injury (ALI) in mice by controlling the oxidative stress status. METHODS: Eighty mice were randomly divided into four groups: group 1 (control group) received 25 µL of saline as a vehicle; group 2 contained E coli-induced ALI mice; group 3 included mice that received MSCs before induction of ALI; group 4 included mice that received MSCs after induction of ALI. Lung samples were isolated and assayed for oxidative stress variables and histopathologic analysis. Total anti-oxidant capacity was measured in broncho-alveolar lavage. RESULTS: Pre- and post-injury MSC injection increased survival, reduced pulmonary edema and attenuated lung injuries in ALI mice. Histologically, MSCs exhibited a considerable degree of preservation of the pulmonary alveolar architecture. An increase of anti-oxidant enzyme activities and a decrease of myeloperoxidase activity and malondialdehyde levels in the MSC recipient groups versus the ALI group were found. Furthermore, the total anti-oxidant capacity and reduced glutathione levels were significantly increased in MSCs recipient groups versus the ALI group. Weak +ve inducible nitric oxide synthase immuno-expression in groups that received MSCs was detected. Pre-injury MSC injection showed better effects than did post-injury MSC injection. CONCLUSIONS: Systemic bone marrow-derived MSC injection was effective in modulating the oxidative stress status in E coli-induced acute lung injury in mice.

Differential effects of eugenol against hepatic inflammation and overall damage induced by ischemia/re-perfusion injury.

Liver injuries, liver tumor resection, and liver transplantation are known to be responsible for ischemia/reperfusion (I/R) injury that, in turn, gives rise to liver damage. This study was undertaken to investigate the possible protective effect of eugenol against the damage induced by I/R in rat livers as well as to explore possible mechanisms of action. Male rats were divided into four groups: sham-operated, I/R only, and two groups that received 10 or 100 mg eugenol/kg/day (Eug10 and Eug100, respectively) for 15 days by gavage and were then subjected to I/R, i.e. an ischemia induced for 45 min followed by re-perfusion for 6 h. The rats were euthanized and liver tissues and blood collected for examination. The results showed that I/R induced massive hepatic structural and functional damage. Eug10-treated rats had improvement in both liver function and structure, and inhibition of I/R-induced increases in serum myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, as well as hepatic nuclear factor-κB (NF-κB) p65 and caspase-3 expression. Eug10 treatment also inhibited the degree of loss in reduced glutathione (GSH) and of rise in malondialdehyde (MDA) levels in liver tissues induced by I/R. In contrast, augmentation of liver damage induced by I/R was noted in Eug100-treated rats, with these hosts displaying significant increases in oxidant, inflammatory, and apoptotic markers relative to levels seen in I/R-only rats. The results of the present study provide the first evidence that a low dose of eugenol may protect the liver against I/R injury in part by decreasing levels of lipid peroxidation, down-regulating inflammatory mediators, and inhibiting apoptosis, and that a larger dose amplifies the liver injury via oxidant and inflammatory effects.

The selective 5-LOX inhibitor 11-keto-ß-boswellic acid protects against myocardial ischemia reperfusion injury in rats: involvement of redox and inflammatory cascades.

Myocardial ischemia induces 5-lipoxygenase (LOX) translocation and leukotriene production in the heart. Leukotrienes increase inflammatory responses aggravating, thereby, ischemia-reperfusion (I/R) injury. This study aimed to investigate whether the selective 5-LOX inhibitor 11-keto-ß-boswellic acid (11-keto BA), in three different dose levels, exert a protective effect on myocardial I/R injury in an in vivo rat heart model. Sixty male Wister rats were used in this study and divided into five equal groups (n=12): GP1, sham-operated receiving normal saline; Gp 2, rats were subjected to 45 min left anterior descending coronary artery ligation followed by 4 h reperfusion to serve as I/R group. Gps 3-5 received 11-keto BA in doses 250, 500, 1,000 mg/kg, respectively, via an oral gavage for 7 days then were exposed to I/R. I/R injury induced a significant elevation in myeloperoxidase activity and gene expression of intracellular adhesion molecules, cyclooxygenase-2, 5-lipooxygenasae, nuclear factor kappa-beta, tumor necrosis factor alpha, nuclear factor (erythroid-derived 2)-like 2, and hemeoxygenease-1 consequently with reduction in glutathione peroxidase in heart tissues. Furthermore, immunohistochemical examination of the heart tissues showed positive immuostaining for both 3-nitrotyrosine and caspase-3 with DNA-ladder formation in all diseased rats. 11-keto BA in three dose levels exerted dose dependent cardioprotective effect manifested by dose-dependent reduction in serum lactate dehydrogenase and infract size through mechanisms related to enhancement of antioxidant capacity and prevention of inflammatory cascades.