Fahad A. Al-Abbasi

Montelukast, a leukotriene receptor antagonist abrogates lipopolysaccharide-induced toxicity and oxidative stress in rat liver

Endotoxemia-induced hepatotoxicity is characterized by disturbed intracellular redox balance, excessive reactive oxygen species (ROS) generation inducing DNA, proteins and membrane lipid damages. In the present study, the protective effects of montelukast (MNT) against Escherichia coli lipopolysaccharides (LPS)-induced oxidative stress were investigated in rat liver. LPS (10mg/kg, i.p.) was injected and the animals were sacrificed 6h after LPS challenge. MNT (10mg/kg) was administered orally for seven successive days before endotoxemia induction. Blood samples were withdrawn for assessing the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and levels of serum total bilirubin, total protein, tumor necrosis factor-alpha (TNF-α) and interleukin 1β (IL-1β). Livers were dissected out and used for histological examination or stored for the determination of malondialdehyde (MDA), protein carbonyl content (PCC), reduced glutathione (GSH) levels, enzymatic activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and myeloperoxidase (MPO). Sepsis significantly increased ALT, AST, ALP, LDH, total bilirubin, TNF-α and IL-1β, MPO, MDA and PCC levels and decreased total protein, GSH and enzymatic antioxidants (CAT, SOD and GSH-Px). MNT decreased the markers of liver injury (AST, ALT, ALP, LDH, and total bilirubin), inflammatory biomarkers (TNF-alpha, IL-1β), MDA, PCC and MPO after LPS challenge. In conclusion, MNT abrogates LPS-induced markers of liver injury and suppresses the release of inflammatory and oxidative stress markers via its antioxidant properties and enhancement enzymatic antioxidant activities.

Anti-inflammatory activity of methyl palmitate and ethyl palmitate in different experimental rat models

Methyl palmitate (MP) and ethyl palmitate (EP) are naturally occurring fatty acid esters reported as inflammatory cell inhibitors. In the current study, the potential anti-inflammatory activity of MP and EP was evaluated in different experimental rat models. Results showed that MP and EP caused reduction of carrageenan-induced rat paw edema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In lipopolysaccharide (LPS)-induced endotoxemia in rats, MP and EP reduced plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). MP and EP decreased NF-κB expression in liver and lung tissues and ameliorated histopathological changes caused by LPS. Topical application of MP and EP reduced ear edema induced by croton oil in rats. In the same animal model, MP and EP reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In conclusion, this study demonstrates the effectiveness of MP and EP in combating inflammation in several experimental models.

Umbelliferone β-D-galactopyranoside exerts an anti-inflammatory effect by attenuating COX-1 and COX-2

Umbelliferone β-D-galactopyranoside (UFG) (benzopyrone) is a member of the coumarin family, found in many plants exhibiting numerous pharmacological actions. The current experiments were carried out to exemplify the anti-inflammatory potential of UFG on chronic inflammation induced by Complete Freund Adjuvant (CFA) (heat killed Mycobacterium tuberculosis) in experimental rats. Arthritis in rats was induced by intradermal administration of CFA (0.05 ml) in the right hind paw, and confirmed by development of paw edema and arthritic index in comparison with normal controls. The anti-arthritic activity of UFG was determined by its ability to inhibit various biochemical markers, viz., pro-inflammatory, antioxidant enzymes, and hematological parameters elevated upon administration of CFA. UFG was also tested for its inhibitory activity against cyclooxygenase-1 (COX-1) and COX-2 via enzyme inhibition assay and the results were monitored spectrophotometrically with a 96-well plate reader. The results of the study showed that UFG in a dose of 10, 20 or 40 mg kg−1 per day, p.o., helps to prevent paw edema and arthritic score development for arthritis in rats. It markedly alters hematological and oxidative stress induced by the adjuvant. Moreover, the changes brought about in inflammation/arthritis serum markers were reverted back to a near normal level upon UFG treatment in a dose dependent manner. Histopathological analysis of the joints of subjects showed UFG significantly decreases mononuclear infiltration and synovial hyperplasia, which confirms the utility of UFG as an anti-arthritic agent. In a COX inhibition assay UFG was found to act prominently to inhibit COX-2 then COX-1, which suggests its plausible mechanism of action. The current study clearly indicates that UFG possesses anti-inflammatory effects against CFA induced arthritis via suppressing COX-2 inhibition.

Lycopene attenuates oxidative stress and heart lysosomal damage in isoproterenol induced cardiotoxicity in rats: A biochemical study

The present study was designed to investigate the cardioprotective potential of lycopene (LYC) on isoproterenol (ISO)-induced oxidative stress and heart lysosomal damage in rats. Male Sprague Dawley rats were pretreated with LYC (4mg/kg, p.o.) once daily for 21 days. After the treatment period, ISO (85mg/kg) was injected subcutaneously, once daily, to rats for 2 days. Hemodynamic parameters, cardiac marker enzymes, antioxidant, and oxidative stress parameters in serum and heart tissues were measured. ISO treated rats showed significant changes in heart rates, heart weights and serum lipid profiles. The activity of aspartate aminotranferase (AST), lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) and cardiac troponin T (cTnT) were increased significantly (p<0.01) in the serum of ISO rats. The levels of lipid peroxides (thiobarbituric acid reactive substances, TBARS), protein carbonyl content (PCC) and neutrophil infiltration marker; myeloperoxidase (MPO) were significantly (p<0.01) increased. In addition, the activities of lysosomal enzymes (beta-glucuronidase, beta-N-acetylglucosaminidase, and cathepsin-d) in the serum and heart of ISO rats were increased significantly. Furthermore, a marked decrease in the levels of serum and cardiac reduced glutathione (GSH), vitamin C and cardiac enzymatic antioxidants; superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were observed. In vitro study confirmed the strong antioxidant effect of LYC on total antioxidant activity. In conclusion, the present study demonstrated that LYC supplementation to ISO rats significantly ameliorated lysosomal membrane damage as well as the alterations in cardiac enzymes, lipid profile and oxidative stress markers. These findings revealed the cardioprotective effects of LYC against ISO-induced oxidative stress and cardiotoxicity in rats. These observed effects are mediated via antioxidant power and free radical scavenging activity of LYC.

Protective Effects of Simvastatin, a Lipid Lowering Agent, against Oxidative Damage in Experimental Diabetic Rats

The present study was undertaken to evaluate the possible protective effects of simvastatin (SMV) against oxidative stress in streptozotocin- (STZ)-induced diabetic rats. Diabetes was induced experimentally in rats by i.p. injection of STZ in a dose of 60 mg/kg bwt. After 5 weeks of STZ injection, there were apparent reductions in the animal body weight and significant increase in blood glucose, HbA1c, urea, creatinine, AST, ALT, and lipid profiles with a concomitant decrease in total hemoglobin, plasma glutathione and vitamin C as compared to the control group. The treatment with SMV at a dose (10 mg/kg, orally) normalized all the above-mentioned biochemical parameters in STZ-induced diabetic rats. In vitro studies confirmed the free radical scavenging and antioxidant activity of SMV. Therefore, the present results revealed that SMV has a protective effect against STZ-induced oxidative damage by scavenging the free radicals generation and restoring the enzymatic and nonenzymatic antioxidant systems.

Umbelliferone β-D-galactopyranoside inhibits chemically induced renal carcinogenesis via alteration of oxidative stress, hyperproliferation and inflammation: possible role of NF-κB

Umbelliferone (7-hydroxycoumarin) possesses strong anti-inflammatory properties and free radical scavenging activity. The intent of the current study was to examine the renal protective efficacy of Umbelliferone β-D-galactopyranoside (UFG) against oxidative stress, inflammation and renal injury in Wistar rats, initiated by diethylinitrosamine (DEN) and promoted by ferric nitrilotriacetate (Fe-NTA). The capacity of UFG to scavenge the reactive nitrogen species (RNS) and reactive oxygen species (ROS) was evaluated and was also scrutinized for its effectiveness in scavenging the hydroxyl (OH), superoxide (O2), nitric acid (NO) and hydrogen peroxide (H2O2) radicals. Renal carcinoma was induced by a single intraperitoneal injection of DEN (200 mg kg−1 bodyweight) and promoted by twice weekly treatment of Fe-NTA (9 mg kg−1) for 22 weeks. To estimate the molecular mechanism involved in the antitumor potential of UFG, its effect on renal tumor inflammation was evaluated; the proinflammatory cytokines included interleukin-1β (IL-1β), interlukin-6 (IL-6) and tumor necrosis factor (TNF-α); the inflammatory mediator included prostaglandin E2 (PGE2), ornithine decarboxylase (ODC) and nuclear factor kappa B cell (NFκB). Serum abnormalities, including creatinine, lactate dehydrogenase (LDH), blood urea nitrogen (BUN) and [3H] thymidine incorporation were also induced. Furthermore, renal lipid peroxidation (LPO), endogenous antioxidant enzymes, phase II metabolizing enzymes and concomitant reduction in glutathione (GSH) were augmented. UFG showed the 95% and 99% antioxidant activity in the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) models. UFG significantly inhibited the RNS and ROS radical and indicated the antioxidant activity (in vitro). The results showed momentous renal markers and oxidative stress protection impaired by UFG. UFG also restored the altered inflammatory and proinflammatory cytokines, which further strengthens the renal protection of UFG in DEN + Fe-NTA induced renal carcinogenesis. These results indicate that UFG is an efficient chemoprotective agent, having the ability to thwart DEN induced and Fe-NTA promoted renal carcinoma in experimental rats.

Didox potentiates the cytotoxic profile of doxorubicin and protects from its cardiotoxicity

The use of adjuvant therapies in cancer treatment is rationalized by potentiating the efficacy and/or protecting from the major side effects of chemotherapeutics. Didox, besides its antioxidant properties, is an inhibitor for DNA synthesis and repair which might recommend its use as adjuvant therapy. Herein, we have studied the effect of didox in potentiating the efficacy of doxorubicin (DOX) against liver cancer cells and protecting from its dose-limiting cardiotoxic effects. Didox combination with DOX significantly decreased in the IC50 of DOX to half its original value in Huh7 and HepG2 liver cancer cell lines. The calculated combination index (CI-value) indicated additive type of drug interaction (CI-value ranged from 0.81 to 0.9). Both didox and DOX significantly blocked the cell cycle in S-phase and their combination significantly increased cell cycle blockade. Also, didox combination significantly increase the caspase-3 level compared to DOX treatment alone. On the other hand, didox (150 mg/kg daily) significantly protected the cardiomyocyte membrane integrity and decreased the intra-cardiac oxidative stress induced by DOX treatment (15 mg/kg). This protective effect was reflected in reverting the cardiomegaly and cardio-pathological features induced by DOX treatment. Also didox prolonged the median survival time of mice treated with DOX and decreased the mortality risk by 3.7 folds. In conclusion, didox significantly potentiated the cytotoxicity of DOX in liver cancer cells and protected from its cardiotoxicity.

Anti-Inflammatory Activity of Pistacia khinjuk in Different Experimental Models: Isolation and Characterization of Its Flavonoids and Galloylated Sugars

The present study aimed at isolating and elucidating the structure of the main components of Pistacia khinjuk L. and exploring its potential anti-inflammatory effect in different experimental models. The extract was evaluated for anti-inflammatory activity by measuring paw volume in three experimental models. Then, prostaglandin E₂ (PGE₂) level, ear edema, tissue myeloperoxidase (MPO) activity, histopathology, nitric oxide (NO) level, and tumor necrosis factor-α (TNF-α) level were assessed. Seven phenolic compounds, mainly flavonoids and galloylated compounds, were isolated from the aqueous methanol extract: gallic acid (1), methyl gallate (2), quercetin-3-O-β-D-⁴C₁-galactopyranoside (hyperin) (3), myricetin-3-O-α-L-¹C₄-rhamnopyranoside (myricitrin) (4), 1,6-digalloyl-β-D-glucose (5), 1,4-digalloyl-β-D-glucopyranoside (6), and 2,3-di-O-galloyl-(α/β)-⁴C₁-glucopyranose (nilocitin) (7). The anti-inflammatory activity was evidenced by decreased carrageenan-induced rat paw edema and PGE₂ elevation. In the croton oil-induced ear edema model, MPO activity was significantly inhibited, and inflammatory histopathological changes were ameliorated. In the rat air pouch model, NO generation and TNF-α release were significantly inhibited. The isolation and nuclear magnetic resonance spectral data of compound 6 from the genus Pistacia are revealed for the first time. Also, P. khinjuk L. aqueous methanol extract possesses anti-inflammatory activity in several experimental models.

The chemomodulatory effects of resveratrol and didox on herceptin cytotoxicity in breast cancer cell lines

Herceptin is considered an essential treatment option for double negative breast cancer. Resveratrol and didox are known chemopreventive agents with potential anticancer properties. The aim of the current study is to investigate the influence of resveratrol and didox on the cytotoxicity profile of herceptin in HER-2 receptor positive and HER-2 receptor negative breast cancer cell lines (T47D and MCF-7 cell lines, respectively). The IC50’s of herceptin in T47D and MCF-7 were 0.133 ± 0.005 ng/ml and 23.3795 ± 1.99 ng/ml respectively. Equitoxic combination of herceptin with resveratrol or didox in T47D significantly reduced the IC50 to 0.052 ± 0.001 and 0.0365 ± 0.001 ng/ml, respectively and similar results were obtained in MCF-7. The gene expression of BCL-xl was markedly decreased in T47D cells following treatment with herceptin/resveratrol compared to herceptin alone. Immunocytochemical staining of HER-2 receptor in T47D cells showed a significant reduction after treatment with herceptin/resveratrol combination compared to herceptin alone. On the contrary, herceptin/didox combination had no significant effect on HER-2 receptor expression. Cell cycle analysis showed an arrest at G2/M phase for both cell lines following all treatments. In conclusion, herceptin/resveratrol and herceptin/didox combinations improved the cytotoxic profile of herceptin in both T47D and MCF-7 breast cancer cell lines.

Anticancer effect of ursolic acid stearoyl glucoside in chemically induced hepatocellular carcinoma.

Hepatocellular carcinoma is one of the leading causes of death in cancer and yet no drug has proven to be a successful candidate for its treatment in advanced stages. Ursolic acid stearoyl glucoside (UASG) is a newly discovered triterpene in Lantana camara and there lies a possibility that it possess anti-hepatocellular carcinoma property. In the present study, we induced hepatocellular carcinoma in Wistar rats by diethylnitrosamine (DENA) and treated it with ursolic acid stearoyl glucoside. The ability to treat hepatocellular carcinoma was measured by comparing biochemical serum markers such as serum alanine aminotransferase, serum aspartate aminotransferase, serum alkaline phosphatase, and the specific marker for hepatocellular carcinoma, alpha fetoprotein. The histological studies of the livers were also performed. The results have shown significant elevated levels of these parameters as compared to normal control and the drug receiving groups have shown significant reduction in these marker levels. Histopathological studies also indicated the reduced liver damage in drug-treated groups. It was noted that a significant and dose-dependent reversal of DENA-diminished activity of antioxidant enzymes like superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase, and the reduced DENA-elevated level of lipid peroxidation (LPO) with a marked change. UASG significantly suppressed free radical formation by scavenging the hydroxyl radicals. It also modulates the levels of LPO and markedly increases the endogenous antioxidant enzymes level in DENA-induced hepatocellular carcinogenesis.