Combination of metformin and hesperidin mitigates cyclophosphamide-induced hepatotoxicity. Emerging role of PPAR-γ/Nrf-2/NF-κB signaling pathway.

Cyclophosphamide (CP) is widely used as an immunosuppressive and chemotherapeutic drug. However, its therapeutic application is restricted by its adverse effects, particularly hepatotoxicity. Both metformin (MET) and hesperidin (HES) have promising antioxidant, anti-inflammatory, and anti-apoptotic effects. Therefore, the principal aim of the current study is to investigate the hepatoprotective effects of MET, HES, and their combinations on the CP-induced hepatotoxicity model. Hepatotoxicity was evoked by a single (I.P) injection of CP (200 mg/kg) on day 7. For this study, 64 albino rats were randomly categorized into eight equal groups; naïve, control vehicle, untreated CP (200 mg/kg, IP), and CP 200 groups treated with MET 200, HES 50, HES 100 or a combination of MET 200 with HES 50 and HES 100 respectively orally daily for 12 days. At the end of the study, the liver function biomarkers, oxidative stress, inflammatory parameters, histopathological and immunohistochemical analysis of PPAR-γ, Nrf-2, NF-κB, Bcl-2, and caspase3 were assessed. CP significantly increased serum ALT, AST, total bilirubin, hepatic MDA, NO content, NF-κB, and TNF-α. Otherwise, albumin, hepatic GSH content, Nrf-2, and PPAR-γ expression decreased considerably compared to the control vehicle group. The combinations of MET200 with HES50 or HES100 induced pronounced hepatoprotective, anti-oxidative, anti-inflammatory, and anti-apoptotic effects on CP-treated rats. The possible explanation of such hepatoprotective effects may be mediated via upregulation of Nrf-2, PPAR-γ, Bcl-2 expression, hepatic GSH content, and marked suppression of TNF-α and NF-κB expression. In conclusion, the current study showed that combining MET and HES revealed a remarkable hepatoprotective effect against CP-induced hepatotoxicity.

Metformin alleviates inflammation in oxazolone induced ulcerative colitis in rats: plausible role of sphingosine kinase 1/sphingosine 1 phosphate signaling pathway.

OBJECTIVES: Ulcerative colitis (UC) is a chronic inflammatory bowel disease that is associated with high sphingosine kinase 1(SPHK1) expression in the colon, however its role in pathogenesis of UC is not clearly understood so, the aim of the present study was to clarify the role of SPHK1 and investigate whether the anti-inflammatory effects of metformin in UC is mediated by Sphingosine kinase 1/sphingosine 1 phosphate (S1P) signaling pathway. MATERIAL AND METHODS: Colitis was induced in adult male wistar rats by intra rectal administration of oxazolone in the fifth and seventh days from initial presensitization. Oxazolone treated rats were divided into untreated oxazolone group, metformin and mesalazine treated groups both in a dose of 100 mg/kg/day orally for 21 days. Along with these groups normal control and saline groups were used .Colitis was assessed by colon length, disease activity index (DAI) and histological examination of colontissue. Plasma samples were used to measure S1P.SPHK1 activity, signal transducer and activator of transcription -3(STAT-3), interleukin-6 (IL-6), nitric oxide (NO), myeloperoxidase activity (MPO), reduced glutathione (GSH) and tissue expression of intracellular cell adhesion molecule -1(ICAM-1) and caspase-3 genes were measured in tissue. RESULTS: Metformin successfully attenuated oxazolone colitis by increasing colon length, decreasing DAI and improved colon histologic picture. Metformin also induced a significant decrease in Plasma SIP, SPHK1 activity, inflammatory, oxidative stress markers, ICAM-1 and Caspase-3 genes expression compared to oxazolone group. CONCLUSION: It is revealed that metformin alleviated inflammation and underlying mechanism may result from inhibition of SPHK1/S1P signaling pathway.

Metformin potentiates the chemotherapeutic effects of doxorubicin on 2-amino-1-methyl-6-phenylimidazo[4,5b] pyridine-induced Mammary Carcinoma in rats.

This study was carried out to evaluate the antitumor activity of Metformin (Met) and its impending utility to potentiate the chemotherapeutic action of doxorubicin on 2-amino-1-methyl-6-phenylimidazo[4,5b]pyridine (PhIP)-induced rat mammary carcinogenesis. Female Sprague -Dawley (SD) rats were divided into seven groups (n = 15 each). Mammary carcinogenesis was induced by the administration of PhIP at a dose of 75 mg/kg by gavage. Met treatment was 2 mg/ml in drinking water for 26 weeks started after the last PhIP dose. Doxorubicin (Dox) treatment started after one month of the last PhIP dose with a dose of 4 mg/kg, i.v. once per week for 4 weeks. Compared to the PhIP group, the latency period of tumors in the PhIP+Dox, PhIP+Met, and PhIP+Dox+Met groups were significantly increased and tumors' incidences and multiplicities were significantly reduced. By immunohistochemistry, carcinomas from the combination treatment groups showed a significant decrease in the labeling indexes (LI%) of cellular proliferation and CD44 compared to the PhIP group while LI% for ERα was significantly decreased in all combination treatment groups compared to the PhIP-administered group. Moreover, the quantitative mRNA expression of ERα was significantly decreased in mammary tumors from PhIP + Dox+Met combined group more than the PhIP + Dox group. However, mRNA expression of EGF was found significantly lower in all combination treatment groups compared to the PhIP group. These findings suggest that Metformin potentiate the antitumor efficacy of doxorubicin and had beneficial effects on PhIP-induced mammary carcinogenesis through the prevention of cellular proliferation and mRNA expression of ERα and EGF.

Targeting IL-10, ZO-1 gene expression and IL-6/STAT-3 trans-signaling by a combination of atorvastatin and mesalazine to enhance anti-inflammatory effects and attenuates progression of oxazolone-induced colitis.

Ulcerative colitis (UC) is a chronic inflammatory disease characterized by diffused inflammation of the colon and rectum mucosa. The pathogenesis of UC is multifactorial, and the exact underlying mechanisms remain poorly understood. This study aims to investigate the effect of mesalazine and atorvastatin combination in enhancing anti-inflammatory effects and attenuates progression of oxazolone colitis in rats. In the present study, male albino rats (N = 60) were divided into six groups (10 rats each), the first two groups served as normal control and a control saline group. Colitis was induced by intra-rectal administration of oxazolone in the 5th and 7th days after pre-sensitization. Then, rats were divided into untreated group, groups treated with mesalazine or atorvastatin or their combination. Colitis was assessed by colon length, body weight, and incidence of diarrhea, rectal bleeding, and histopathology of colon tissue. Colon tissues were used for measuring interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), IL-13, signal transducer and activator of transcription-3 (STAT-3), myeloperoxidase activity (MPO), reduced glutathione(GSH), and tissue expression of IL-10, tight junction protein zonula occludens (ZO-1), and caspase-3 genes. The combination therapy significantly attenuated progression of UC by decreasing incidence of diarrhea, rectal bleeding, weight loss, IL-13, IL-6, TNF-α, STAT-3, caspase-3, and MPO activity and significantly increased IL-10, ZO-1, colon length, and GSH content, and these effects were more superior to single drugs. These findings showed that combination therapy was able to ameliorate progression of UC and enhance anti-inflammatory effects possibly by restoring IL-10 and ZO-1 levels and limiting IL-6/STAT-3 trans-signaling.

Study of Serum Levels of Some Oxidative Stress Markers in Children with Helicobacter pylori Infection.

BACKGROUND: Helicobacter pylori are gram-negative spiral shaped bacteria, with sheathed flagella. H. pylori infection is one of the most common chronic infections in humans. Infection is usually acquired during childhood, and becomes a lifelong infection in most people unless treated. The aim of this study was to evaluate serum levels of oxidative stress indices in children with H. pylori infection. MATERIAL AND METHODS: The present study was carried out on 60 children infected with H. pylori including 28 males, 32 females with their age ranging from 7-10 years and mean age value of 8.5 ± 1.65 ( Group I). This study included also 60 children as a control group including 26 males, 34 females with their age ranging from 7-11 and mean age value of 8.99 ± 1.63 (Group II). For all children in groups I the following were done: Diagnosis of H. pylori infection through H. pylori stool antigen testing using enzyme immunoassay kit and gastric antrum mucosal biopsies which were tested for urease activity using Campylobacter like organism test (CLO test). Measurements of serum oxidative stress markers including Superoxide dismutase (SOD), Malondialdhyde, Glutathione, Catalase and Nitric oxide were done in patients and controls. RESULTS: Serum nitric oxide and reduced glutathione were significantly lower in patients compared to controls while serum MDA, Serum catalase and Serum SOD were significantly higher in patients compared to controls (nitric oxide was 91.111 ±6.366 in patients versus 107.211±2.121 in controls with p value of 0.001, reduced glutathione in patients was 2.457± 0.081 versus 2.889±0.491 in controls with p value of 0.001, serum MDA in patients was 140.22±5.18 versus 116.22±2.98 in controls with p value of 0.001, catalase was 401.645± 4.344 versus 278.221±71.712 in controls with p value of 0.001 and SOD in patients was 16.936±9.145 versus 5.578±0.231 in controls with p value of 0.001). CONCLUSION: H. pylori infection is associated with oxidative stress with significantly lower serum nitric oxide and reduced glutathione and significantly higher serum MDA, catalase and SOD in patients compared to controls. RECOMMENDATIONS: Antioxidants may be beneficial adjuvant treatment in H. pylori infection as H. pylori infection is associated with oxidative stress.

Protective effects of mirtazapine and chrysin on experimentally induced testicular damage in rats.

Mirtazapine is an antidepressant with prominent antioxidant effects. Chrysin, a natural flavone, exhibits multiple pharmacological actions. This study was designed to investigate the potential protective effects of chrysin and mirtazapine against nitrofurazone-induced testicular damage in rats. Possible underlying mechanisms such as oxidative stress, inflammation and apoptosis were also investigated. Testicular damage was induced by oral administration of nitrofurazone (50mg/kg/day) for two weeks. Chrysin (25 and 50mg/kg/day, p.o.) and mirtazapine (15 and 30mg/kg/day, p.o.) were applied for three weeks, starting one week before nitrofurazone administration. Prophylactic treatment with chrysin and mirtazapine attenuated the elevation of serum acid phosphatase enzyme activity and halted the decline of sperm count and sperm viability resulted from nitrofurazone administration. Moreover, both agents ameliorated nitrofurazone-induced lipid peroxidation, glutathione depletion, elevation in tumor necrosis factor-α level and reduction in c-kit level in rat testes. With respect to apoptosis, immunohistochemical analysis revealed that chrysin and mirtazapine reduced the expression of caspase-3 in testicular tissue which was induced by nitrofurazone. Histopathological findings further supported the protective effects of both drugs against nitrofurazone-induced testicular injury. These findings suggest that the cytoprotective effects of chrysin and mirtazapine on rat testes were associated with suppression of oxidative stress and apoptotic tissue damage. Generally, chrysin prophylactic treatment showed a superior testicular protection than mirtazapine at the tested doses.

Combination of Sitagliptin and Silymarin ameliorates liver fibrosis induced by carbon tetrachloride in rats.

Liver fibrosis is a common pathological condition that occurs in most conditions associated with chronic liver injury. Silymarin is a herbal product widely used for its hepatoprotective effect. Sitagliptin, a dipeptidyl peptidase-4 inhibitor (DPP4-I), is clinically used as an oral antidiabetic agent. This study was designed to investigate the effects of Sitagliptin, Silymarin, and their combination on established liver fibrosis in carbon tetrachloride (CCl4) rat model. Male albino rats received intraperitoneal injections of CCl4 three times a week for 7 weeks, as well as daily oral treatments of Sitagliptin (100mg/kg) or Silymarin (100mg/kg) or their combination during the 7 weeks of intoxication. Hepatic fibrotic changes were evaluated by measuring hepatic enzymes (ALT, AST, ALP, and GGT) and markers of fibrosis (transforming growth factor ß1 (TGF-ß1), tissue 4-hydroxyproline level, histopathological score), oxidative stress (MDA, GSH, and NOx levels), inflammation (interleukin-6) as well as markers of HSCs activation (α-smooth muscle actin (α-SMA) expression). The injected rats with CCl4 for 7 weeks resulted in a marked elevation of hepatic fibrotic changes and reduction of GSH level, while the combination therapy showed a significant decrease in the former one and a significant increase in the later. In conclusion, this study shows that the combination therapy is more beneficial than monotherapy in ameliorating liver fibrosis in rats. Our findings suggest that Sitagliptin alone or in combination with Silymarin may introduce a new strategy for treating liver fibrosis in humans.

Celecoxib and omega-3 fatty acids alone and in combination with risperidone affect the behavior and brain biochemistry in amphetamine-induced model of schizophrenia.

The implications of oxidative stress and neuro-inflammation in the pathogenesis of schizophrenia have been elucidated. Despite their effectiveness against positive symptoms of schizophrenia, antipsychotics have limited effectiveness against negative and cognitive symptoms and are associated with remarkable adverse effects. The use of celecoxib or omega-3 in schizophrenia may have beneficial effects. This study aimed to evaluate the possible efficacies of celecoxib, omega-3 or the combination of celecoxib+risperidone and omega-3+ risperidone compared to risperidone on the behavior and brain biochemistry in rats. In the present study, an amphetamine-induced model of schizophrenia in adult male rats was used to evaluate the effects of celecoxib, omega-3, celecoxib+risperidone and omega-3+ risperidone on the behavior of animals and on brain lipid peroxidation or tumor necrosis factor-alpha. In the water maze task, celecoxib, omega-3, celecoxib+risperidone, omega-3+ risperidone significantly decreased the latency time compared to amphetamine-treated group. Celecoxib, omega-3, celecoxib+risperidone, omega-3+risperidone also significantly reversed the decreased spontaneous alternation induced by amphetamine in the Y-maze task. In the social interaction task, groups treated with celecoxib, omega-3, celecoxib+risperidone, omega-3+ risperidone spent less time to recognize foreign animals than animals in the amphetamine-treated group. Increased brain MDA and TNF-α levels due to amphetamine were significantly reduced in groups treated with celecoxib+risperidone or omega-3+ risperidone. The present findings showed that celecoxib or omega-3 can attenuate amphetamine- induced behavioral impairment and these effects may be associated with their ability to decrease lipid peroxidation and cytokine release. Celecoxib or omega-3 may be promising candidates as adjuvant therapy for schizophrenia.

Combination of telmisartan with sildenafil ameliorate progression of diabetic nephropathy in streptozotocin-induced diabetic model.

Diabetic nephropathy (DN) is a leading cause of end-stage renal disease in the world. Several signaling pathways are involved in the pathogenesis of DN including elevation in level of angiotensin II, formation of advanced glycation end products (AGE), activation of protein kinase c (PKC), and lipid accumulation. These pathways activate one another mutually leading to oxidative stress, increasing expression of transforming growth factor beta-1(TGF-ß 1) and release of interleukins and adhesion molecules, so the aim of this study is to interrupt more than pathogenic pathway to ameliorate the progression of DN. In the present study, white male rats (N=48) were divided into six groups (8 rats each), the first two groups served as normal control and a control vehicle group while the remaining four groups were rendered diabetic by a single intraperitoneal injection of Streptozotocin (STZ) and being left for 4 weeks to develop DN. Thereafter, the rats were divided into DN group, DN group receiving Telmisartan or Sildenafil or Telmisartan Sildenafil combination. After the specified treatment period, urine samples were collected (using metabolic cages) to measure proteinuria, animals were then euthanized, blood and tissue samples were collected for measurement of Blood glucose,BUN, S.Cr, LDL, NO, TGF-ß1, IL-1ß, AGEPs, and SOD. The combination therapy showed significant decrease in BUN, S.Cr,LDL, TGF-ß1, IL-1ß, Proteinuria and AGEPs and significant increase in SOD and NO. The findings showed that combination therapy was able to ameliorate DN and that the effects were superior to the single drugs alone.

Bone marrow mononuclear cells enhance anti-inflammatory effects of pravastatin against isoproterenol-induced myocardial infarction in rats.

The current study investigated the combinatorial effect of pravastatin (PRAV) and bone marrow mononuclear cells (BM-MNC) on acute myocardial infarction (AMI) induced experimentally in rats. After induction of MI, rats were given oral PRAV (20 mg/kg/day) for 28 days or a bolus intravenous injection (via lateral vein) of a total of 14 × 10(6) autologous BM-MNC or a combination of both. Serum brain natriuretic peptide (BNP) and histologic changes in cardiac tissues were assessed. Cardiac contents of lipid peroxides, superoxide dismutase (SOD) and inflammatory biomarkers including tumor necrosis factor (TNF)-α and interleukin (IL)-1ß as well as vascular endothelial growth factor (VEGF) and nitric oxide (NO) were also measured. Combined PRAV and BM-MNC treatment significantly suppressed serum BNP. Cardiac cell apoptosis and inflammatory cell infiltration in heart tissue decreased significantly in both the PRAV and the PRAV + BM-MNC groups. Cardiac lipid peroxides along with TNFα and IL-1ß levels were significantly reduced in both the PRAV and PRAV + BM-MNC hosts with an increase in SOD levels. However, the combined treatment increased cardiac NO levels and did not modify cardiac VEGF levels. The current results indicated that administration of BM-MNC improved the therapeutic efficacy of PRAV treatment by improving the morphology of infarcted hearts as well as decreasing inflammation in a host, but did not do so by inducing therapeutic angiogenesis.

The potential role of cyclooxygenase-2 inhibitors in the treatment of experimentally-induced mammary tumour: does celecoxib enhance the anti-tumour activity of doxorubicin?

The potential anti-tumour activity of non-steroidal anti-inflammatory drugs (NSAIDS) has been previously discussed. This study was undertaken to assess the possible anti-tumour activity of the cyclooxygenase-2 (COX-2) inhibitor; celecoxib in an animal model of mammary carcinoma; the solid Ehrlich carcinoma (SEC). The possibility that celecoxib may modulate the anti-tumour activity of doxorubicin on the SEC was also studied. Some of the possible mechanisms underlying such modulation were investigated. The anti-tumour activity of celecoxib (25 mg kg(-1)), diclofenac (12.5 mg kg(-1)) and doxorubicin (2 mg kg(-1)) either alone or in combination were investigated on SEC in vivo through the assessment of tumour growth delay (TGD) and tumour volume (TV), changes in tumour DNA content and nitric oxide (NO) levels, immunohistochemical staining of the tumour suppressor gene product; p53 histopathological examination and determination of apoptotic index of SEC. In addition, the influence of these drugs on the DNA fragmentation pattern of Ehrlich carcinoma cells (ECC) was studied. It was found that both celecoxib and diclofenac lack the anti-tumour activity on SEC. In addition there was a significant increase in doxorubicin anti-tumour activity when administered in combination with celecoxib. Moreover, it was found that both celecoxib and diclofenac have the potential to inhibit the function of P-glycoprotein (P-gp) in ECC using rhodamine uptake and efflux assays. Therefore, the current study suggested the chemosensitizing potential of celecoxib in the SEC animal model of mammary tumour, which could be explained in part on the basis of inhibition of P-gp function, with possible enhancement of doxorubicin anti-tumour activity.