Hatem A. Salem

Nilotinib counteracts thioacetamide-induced hepatic oxidative stress and attenuates liver fibrosis progression.

The aim of this study was to evaluate and compare the effects of imatinib and nilotinib to that of silymarin on established liver fibrosis and oxidative stress in a thioacetamide (TAA) rat model. Male Wistar rats received intraperitoneal (i.p.) injections of TAA (150 mg/kg, twice weekly) for 12 weeks. Daily treatments with imatinib (10 mg/kg), nilotinib (10 mg/kg), and silymarin (100 mg/kg) were administered orally during the last 4 weeks of TAA‐administration. At the end of the study, hepatic damage was evaluated by analysis of liver function tests in serum. Hepatic histopathology and collagen content were employed to quantify liver fibrosis. Hepatic oxidative stress was assessed by measuring malondialdehyde (MDA), 4‐hydroxynonenal (4‐HNE), total nitrate/nitrite (NOx), and reduced glutathione (GSH) contents, as well as myeloperoxidase (MPO) and superoxide dismutase (SOD) activities. Nilotinib, silymarin and, to a lesser extent, imatinib treatments ameliorated TAA‐induced hepatic oxidative stress and damage as indicated by hepatic MDA, 4‐HNE, NOx, GSH, MPO and SOD levels, as well as liver function tests. Hepatic histopathology results revealed that nilotinib, imatinib, and silymarin treatments decreased the mean score of fibrosis in TAA‐treated rats by 24, 14, and 3%, respectively. However, nilotinib and silymarin, but not imatinib, treatments decreased hepatic collagen content in TAA‐treated rats by 17 and 36%, respectively. In conclusion, we demonstrated for the first time that nilotinib not only protected against hepatic oxidative stress, but also slowed down liver fibrosis progression. Thus, we provide the first evidence that nilotinib might be a promising anti‐fibrotic drug.

Effect of Zinc on the Anti-Inflammatory and Ulcerogenic Activities of Indometacin and Diclofenac

In the present study, the potential anti-inflammatory activity of zinc sulfate (zinc) has been examined in rats with acute and chronic inflammation. Additionally, we studied the effect of the concurrent administration of zinc on the anti-inflammatory activity of indometacin and diclofenac and their gastric side effects. Oral or subcutaneous administration of zinc (25 and 15 mg/kg, respectively) significantly reduced carrageenan-induced paw edema. Subcutaneous co-administration of zinc (15 mg/kg) and indometacin (5 mg/kg) or diclofenac (10 mg/kg) resulted in a further reduction in paw edema which was more than either that produced by either agent alone. However, after oral co-administration of zinc and diclofenac the reduction in paw edema was not significantly different from that produced by either zinc or diclofenac alone. In rats with chronic inflammation, the administration of zinc (5 mg/kg s.c. for 7 days) proved as effective as either indometacin (3 mg/kg) or diclofenac (5 mg/kg). Co-administration of zinc with indometacin or diclofenac did not affect the level of activity of either drug. Co-administration of zinc did not affect the ulcerogenic effect of indometacin expressed as the ulcer index. In contrast to indometacin, administration of zinc markedly reduced the ulcerative action of diclofenac. In conclusion, zinc supplementation may contribute significantly to the treatment of inflammation. The combination of zinc with other anti-inflammatory drugs may provide beneficial additive effects and reduce their gastric hazards, particularly with diclofenac.

Protective effect of allicin against gentamicin-induced nephrotoxicity in rats

In this study, the modulator effect of allicin on the oxidative nephrotoxicity of gentamicin in the kidneys of rats was investigated by determining indices of lipid peroxidation and the activities of antioxidant enzymes, as well as by histological analyses. Furthermore, the effect of allicin on gentamicin induced hypersensitivity of urinary bladder rings to ACh was estimated. Twenty-four male Wistar albino rats were randomly divided into three groups, control, gentamicin (100mg/kg, i.p.) and gentamicin+allicin (50mg/kg, orally). At the end of the study, all rats were sacrificed and then urine, blood samples and kidneys were taken. Gentamicin administration caused a severe nephrotoxicity as evidenced by an elevated kidney/body weight ratio, serum creatinine, blood urea nitrogen (BUN), serum lactate dehydrogenase (LDH) and proteinuria with a reduction in serum albumin and creatinine clearance as compared with control group. In addition, a significant increase in renal contents of malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NOx) and tumor necrosis factor-alpha (TNF-α) concomitantly with a significant decrease in renal reduced glutathione (GSH) and superoxide dismutase (SOD) activities was detected upon gentamicin injection. Exposure to gentamicin increased the sensitivity of isolated urinary bladder rings to ACh and induced acute renal tubular epithelial cells necrosis. Administration of allicin significantly decreased kidney/body weight ratio, serum creatinine, LDH, renal MDA, MPO, NOx and TNF-α while it significantly increased creatinine clearance, renal GSH content and renal SOD activity when compared to gentamicin-treated group. Additionally, allicin significantly reduced the responses of isolated bladder rings to ACh and ameliorated tissue morphology as evidenced by histological evaluation. Our study indicates that allicin exerted protection against structural and functional damage induced by gentamicin possibly due to its antioxidant, anti-inflammatory and immunomodulatory properties in addition to its ability to retaining nitric oxide level.

Crocin mediated amelioration of oxidative burden and inflammatory cascade suppresses diabetic nephropathy progression in diabetic rats

Diabetic Nephropathy (DN) is one of the main complications associated with diabetes mellitus. Persistently elevated blood glucose level drives histopathological changes in renal tissues that hinder normal kidney functions. In the current study, crocin; the main bioactive constituent of Crocus sativus was investigated as a reno-protective agent against DN by virtue of its numerous pharmacological activities. Diabetes was induced in male Sprague-Dawely rats through intravenous injection of streptozocin (STZ) (50 mg/kg), DN was confirmed eight weeks post diabetes induction. Daily oral crocin for eight weeks (20 mg/kg) significantly reduced blood glucose level with a significant increase in insulin level. Moreover, crocin improved impaired kidney functions as manifested in reduction of serum creatinine levels, blood urea nitrogen and proteinuria with concomitant increase in urinary creatinine clearance. Furthermore, biomarkers of cell injury and tissue necrosis like LDH activity was significantly reduced, kidney content of NOS significantly declined likewise. In addition, renal antioxidants such as SOD, GSH and serum catalase activity significantly increased with concomitant reduction of kidney MDA; biomarker of oxidative load. Kidney content of toll-like receptors 4 and IL-6 significantly declined with simultaneous suppression of nuclear factor kappa-B (NF-κB/p65) protein expression and immuno-staining in rat renal cortex. Furthermore, crocin inhibited progression of renal fibrosis as seen with reduction of renal hydroxyproline and collagen content, TGF-β immuno-staining and Massons Trichrome positive tissue. Histopathologically, crocin pretreatment was associated with minimal renal damage with fewer fibrotic lesions. There was a concomitant restoration of renal tubules integrity with preservation of glomerular space area. In conclusion, crocins ameliorative impact on DN may be attributed to its free radicals scavenging properties, its ability to enhance host antioxidant defense system and its ability to inhibit inflammatory and fibrotic cascades activation.

The NF-κB inhibitor celastrol attenuates acute hepatic dysfunction induced by cecal ligation and puncture in rats

Acute hepatic dysfunction associating sepsis is mediated mainly by toll-like receptor-4 (TLR-4)/nuclear factor kappa-B (NF-κB) inflammatory pathway. This study explores potential hepatoprotective effect of the NF-κB inhibitor celastrol in cecal ligation and puncture (CLP) model in rats. Protective effect of celastrol (1mg/kg, i.p., 1h before CLP) was illustrated after 24h by preventing CLP-induced hepatic histopathological changes and elevation in serum hepatic biomarkers [alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB) and gamma aminotransferase (γ-GT)] without affecting mortality. Celastrol anti-inflammatory effect was illustrated by inhibiting increased serum and hepatic mRNA expression of interleukin-6 (IL-6) without affecting IL-10 elevation. Furthermore, celastrol inhibited CLP-induced elevations in hepatic mRNA expression of nuclear factor inhibitory protein kappa-B alpha (NFκBia), TLR-4, 5-lipoxygenase (5-LOX) and prevented NF-κB/p65 nuclear translocation and activation. In conclusion, celastrol prevented CLP-induced acute hepatic dysfunction through its anti-inflammatory effect by attenuating NF-κB activation, TLR-4 and 5-LOX expression with subsequent reduction in pro-inflammatory IL-6.

Crocin Reverses Unilateral Renal Ischemia Reperfusion Injury-Induced Augmentation of Oxidative Stress and Toll like receptor-4 Activity

Renal Ischemia (RI) usually develops as a secondary manifestation of hypertension, various cardiovascular disorders and renal transplantation. It exerts hypoxic oxidative stress to kidneys, together with stimulation of several immune-mediated inflammatory cascades. Such events eventually damage renal tubules and glomeruli, driving acute kidney injury (AKI) and ultimately, renal failure. Crocin; the main bioactive constituent of Crocus sativus extract has been reported to demonstrate numerous pharmacological merits. In the current study, unilateral renal ischemia reperfusion injury (URIRI) was induced in rats by unilateral clamping of the left renal pedicle for 45 min followed by 24 h of reperfusion. Daily pre-treatment with crocin (20 mg/kg, orally) for 7 days, significantly improved all signs of renal injury. Biochemically, kidney functions; including serum creatinine (Sr Cr), blood urea nitrogen (BUN), proteinuria and creatinine clearance (Cr Cl) significantly improved. Inflammatory biomarkers; serum lactate dehydrogenase (LDH) and kidney nitric oxide (Nos) contents significantly declined. Oxidant/antioxidant balance was significantly restored; manifested in recovery of renal superoxide dismutase (SOD) activity, glutathione (GSH) concentration, malondialdehyde (MDA) content and restoration of serum catalase activity. Kidney contents of inflammatory cytokine interleukin-6 (IL6) and toll-like receptors 4 (TLR4) significantly declined as well. Histopathologically, crocin pretreatment resulted in signs of improvement with minimal renal lesions with significant decrease in renal inflammatory cells count. In conclusion, crocin induced restoration of normal kidney functions is mediated through multiple mechanisms including mainly attenuation of oxidative stress and inflammation via down-regulation of renal TLR4 and IL6 expression.

Attenuation of Bleomycin-induced pulmonary fibrosis in rats by flavocoxid treatment

Abstract Pulmonary fibrosis is a progressive fatal lung disorder with significantly high mortality rates. Bleomycin (BLM) is one of the most commonly used chemotherapeutic agents for treatment of several carcinomas. The most severe adverse effect of BLM is pulmonary toxicity; therefore, BLM has been repeatedly reported to be considered amongst the most widely used agents for induction of experimental pulmonary fibrosis. In the current study, flavocoxid has been investigated for its ability to ameliorate BLM-induced pulmonary fibrosis. BLM was instilled intratracheally and flavocoxid was administered orally (20 mg/kg) for 5 weeks; one week pre- and 5 weeks post BLM instillation. Flavocoxid significantly decreased lung/body weight index, BALF’s lactate dehydrogenase activity, total protein content and total cell count, lymphocyte and neutrophil counts. Flavocoxid significantly decreased lung MDA content, increased lung GSH content, SOD activity, serum total antioxidant capacity and decreased lung NO content. Moreover, flavocoxid reduced lung content of IL-10. In addition, flavocoxid significantly ameliorated histological changes and prevented collagen deposition with paralleled decrease in lung hydroxyproline content. In conclusion; flavocoxid can be proposed to be a potential therapeutic agent for management of pulmonary fibrosis.

EFFECT OF HIGH LIPID DIET AND ALLOPURINOL ON THE DEVELOPMENT OF EXPERIMENTALLY INDUCED ARTHRITIS IN RATS

Male albino rats were fed a high lipid diet for 5 consecutive weeks. We studied the development of paw inflammation after an injection with Freunds complete adjuvant. Increasing the lipid content of the diet significantly increased the rate of paw inflammation. Also the effect on this process of oral administration of a xanthine oxidase inhibitor (allopurinol, 50 mg/kg) for 15 consecutive days was studied. Results indicated that inflammation was significantly inhibited by allopurinol.

Vildagliptin/pioglitazone combination improved the overall glycemic control in type I diabetic rats

Type I diabetes (TID) is generally assumed to be caused by an immune associated, if not directly immune-mediated, destruction of pancreatic β-cells. In patients with long-term diabetes, the pancreas lacks insulin-producing cells and the residual β-cells are unable to regenerate. Patients with TID are subjected to a lifelong insulin therapy which shows risks of hypoglycemia, suboptimal control and ketosis. In this study, we investigated the potential role of vildagliptin (Vilda) alone or in combination with pioglitazone (Pio), as treatment regimens for TID using streptozotocin (STZ)-induced TID model in rats. Daily oral administration of Vilda (5 mg/kg) alone or in combination with Pio (20 mg/kg) for 7 weeks significantly reduced blood glucose levels and HbA1c. It increased serum insulin levels and decreased serum glucagon. It also showed a strong antioxidant activity. Immunohistochemical analysis showed a marked improvement in β-cells in treated groups when compared with the diabetic group, which appeared in the normal cellular and architecture restoration of β-cells in the islets of Langerhans. Vilda alone or in combination with Pio has the ability to improve the overall glycemic control in type I diabetic rats and may be considered a hopeful and effective remedy for TID.

Levocetirizine Pretreatment Mitigates Lipopolysaccharide-Induced Lung Inflammation in Rats

This research was conducted to investigate possible protective influences of levocetirizine, a nonsedating H1 antihistamine, against lipopolysaccharide (LPS)-induced lung injury in rats. Male Sprague Dawley rats received either levocetirizine (1 mg/kg/day, orally) or the vehicle of the drug (2 ml/kg/day, orally) for 1 week before a single IP injection of LPS (7.5 mg/kg). A group of normal rats served as control. The experiments were terminated 18 h after the LPS challenge. Serum C-reactive protein levels were determined. Moreover, total cell count, lactate dehydrogenase (LDH) activity, protein levels, and total NOx were evaluated in bronchoalveolar lavage fluid (BALF). Pulmonary edema was evaluated as the wet/dry lung weight ratio. Lung tissue homogenate was assessed for antioxidant/pro-oxidant status. BALF and lung tissue levels of tumor necrosis factor-α (TNF-α) were assessed. Lungs were examined for histological alterations. LPS-mediated lung injury was manifested by pulmonary edema, leukocyte infiltration, oxidative stress, and inflammation. Levocetirizine attenuated lung edema and mitigated the increases in BALF protein levels, LDH activity, and lung leukocyte recruitment in LPS-challenged rats. Additionally, TNF-α protein levels in BALF and lung tissue were diminished by levocetirizine administration. Levocetirizine also exhibited a potent antioxidant activity as indicated by a decrease in lung tissue levels of malondialdehyde and an enhancement of superoxide dismutase activity. Histological examination of lung tissues confirmed the beneficial effect of levocetirizine against LPS-induced histopathological alterations. In conclusion, levocetirizine may offer protection against lung tissue damage and inflammation in LPS-challenged rats.