GASTRO-PROTECTION OF ATORVASTATIN IN INDOMETHACIN-INDUCED ULCER: ROLE OF TUMOR NECROSIS FACTOR-ALPHA AND PROSTAGLANDINS

Using non-steroidal anti-inflammatory drugs as over-the-counter pain-killers may predispose to gastric ulcer as a side effect.The objective of this study is to investigate the possible benefit of a common statin used in hyperlipedemic patients;atorvastatin (AtoR), in ameliorating the ulcerogenic effect of indomethacin (IndoM), and to explore the possible mechanismsinvolved. AtoR (10 mg/kg/day) was administered orally for 7 days. At day 7, gastric ulcer was induced by a single dose ofIndoM (40 mg/kg i.p.), with or without AtoR pre-treatment. IndoM induced gastric ulcer as evident by notable gastriculceration in histopathological sections compared to normal control. Gastric tissue in rats receiving IndoM showedsignificantly higher oxidative stress markers as lipid peroxidation represented by increased malondialdehyde (MDA)content, with significant decrease in gastric tissue nitric oxide (NO) and prostaglandin E2 (PGE2) levels, as well as reductionin catalase and superoxide dismutase antioxidant enzymatic activities. In addition, IndoM induced inflammatory signs asshown by the significant increase in tumor necrosis factor-alpha (TNF-α) level assessed via ELISA. Pre-administration ofAtoR significantly decreased ulcer index (16±1) compared to that of IndoM alone (34±2). In addition, AtoR restored normalgastric histological structure and reverted oxidative and inflammatory markers tested. AtoR confers gastro-protection againstIndoM-induced ulceration via reducing gastric oxidative stress and increasing gastric NO and PGE2 levels, as well asdecreasing the inflammatory marker; TNF-α

Fluorescence Spectrometric Determination of Drugs Containing α-Methylene Sulfone/Sulfonamide Functional Groups Using N1-Methylnicotinamide Chloride as a Fluorogenic Agent

A simple spectrofluorometric method has been developed, adapted, and validated for the quantitative estimation of drugs containing α-methylene sulfone/sulfonamide functional groups using N1-methylnicotinamide chloride (NMNCl) as fluorogenic agent. The proposed method has been applied successfully to the determination of methyl sulfonyl methane (MSM) (1), tinidazole (2), rofecoxib (3), and nimesulide (4) in pure forms, laboratory-prepared mixtures, pharmaceutical dosage forms, spiked human plasma samples, and in volunteer's blood. The method showed linearity over concentration ranging from 1 to 150 μg/mL, 10 to 1000 ng/mL, 1 to 1800 ng/mL, and 30 to 2100 ng/mL for standard solutions of 1, 2, 3, and 4, respectively, and over concentration ranging from 5 to 150 μg/mL, 10 to 1000 ng/mL, 10 to 1700 ng/mL, and 30 to 2350 ng/mL in spiked human plasma samples of 1, 2, 3, and 4, respectively. The method showed good accuracy, specificity, and precision in both laboratory-prepared mixtures and in spiked human plasma samples. The proposed method is simple, does not need sophisticated instruments, and is suitable for quality control application, bioavailability, and bioequivalency studies. Besides, its detection limits are comparable to other sophisticated chromatographic methods

Capsaicin ameliorate pulmonary fibrosis via antioxidant Nrf-2/ PPAR- γ pathway activation and inflammatory TGF-β1/ NF-κB/COX II pathway inhibition

Bleomycin is an effective antibiotic with a significant anticancer properties, but its use is limited due to its potential to induce dose-dependent pulmonary fibrosis. Therefore, this study aimed to assess the therapeutic potential of Capsaicin as an additional treatment to enhance patient tolerance to Bleomycin compared to the antifibrotic drug Pirfenidone. Pulmonary fibrosis was induced in rats through by a single intratracheal Bleomycin administration in day zero, followed by either Capsaicin or Pirfenidone treatment for 7 days. After the animals were sacrificed, their lungs were dissected and examined using various stains for macroscopic and histopathological evaluation. Additionally, the study assessed various antioxidant, anti-inflammatory, and antifibrotic parameters were assessed. Rats exposed to Bleomycin exhibited visible signs of fibrosis, histopathological alterations, increased collagen deposition, and elevated mucin content. Bleomycin also led to heightened increased inflammatory cells infiltration in the bronchoalveolar lavage, elevated fibrosis biomarkers such as hydroxyproline, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta (TGF-β1), increased inflammatory markers including tumor necrosis factor-alpha (TNF-α), interlukine-6 (Il-6), interlukine-1β (Il-1β) nuclear factor-kappa B (NF-κB), and Cyclooxygenase-2 (COX-2), and transforming growth factor-beta (TGF-β1),. Furthermore, it reduced the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ), increased oxidative stress biomarkers like nitric oxide (NO), malondialdehyde (MDA), myeloperoxidase (MPO) and protein carbonyl. Bleomycin also decreased the expression of nuclear factor erythroid 2–related factor 2 (Nrf-2), reduced glutathione (GSH), total antioxidant capacity, and the activities of catalase and superoxide dismutase (SOD). Treating the animals with Capsaicin and Pirfenidone following Bleomycin exposure resulted in improved lung macroscopic and microscopic characteristics, reduced collagen deposition (collagen I and collagen III) and mucin content, decreased inflammatory cell infiltration, lowered levels of hydroxyproline, α-SMA, and TGF-β1, decreased TNF-α, Il-6, Il-1β, NF-κB, and COX-2, increased PPAR-γ and Nrf-2 expression, and improvement improved in all oxidative stress biomarkers. In summary, Capsaicin demonstrates significant antifibrotic activity against Bleomycin-induced lung injury that may be attributed, at least in part, to the antioxidant and anti-inflammatory activities of Capsaicin mediated by upregulation of PPAR-γ and Nrf-2 expression and decreasing. TGF-β1, NF-κB and COX II proteins concentrations

Despite Blocking Doxorubicin-Induced Vascular Damage, Quercetin Ameliorates Its Antibreast Cancer Activity

Quercetin is a naturally occurring flavonol present in many foods. Doxorubicin is an effective anticancer agent despite its dose-limiting cardiovascular toxicity. Herein, we investigated the potential protective effects of quercetin against doxorubicin-induced vascular toxicity and its effect on the therapeutic cytotoxic profile of doxorubicin in breast cancer cell lines. The incubation of isolated aortic rings with doxorubicin produced concentration-dependent exaggeration of vasoconstriction responses to phenylephrine but impaired vasodilation responses to acetylcholine. Coincubation with quercetin completely blocked the exaggerated vasoconstriction responses and the impaired vasodilation. In addition, doxorubicin incubation increased reactive oxygen species generation from the isolated aorta, while coincubation with quercetin inhibited ROS generation back to normal values. On the other hand, quercetin in combination with doxorubicin, doubled the IC50 of doxorubicin alone in MCF-7 cells from 0.4±0.03 to 0.8±0.06 μM. To a lesser extent, the IC50 of doxorubicin did not change after combination with quercetin in MDA-MB-231 cells. These findings indicate a significant antagonistic interaction between quercetin and doxorubicin in the aforementioned cell lines. Only in T47D cells, quercetin combination with doxorubicin was an additive interaction (CI−value=1.17). Yet, quercetin significantly impaired the immediate phase of intracellular ROS generation by doxorubicin within breast cancer cells from 125.2±3.6% to 102.5±3.9% of control cells. Using annexin-V/FITC staining technique, the quercetin/doxorubicin combination showed a significantly lower percent of apoptotic cells compared to doxorubicin alone treated cells. Cell cycle distribution in breast cancer cells was performed using DNA content flowcytometry after propidium iodide staining. Quercetin induced significant accumulation of cells in the S phase as well as in the G2/M phase within both MCF-7 and MDA-MB-231 cell lines and interfered with doxorubicin-induced cell cycle effects. Interestingly, quercetin was found to inhibit the P-glycoprotein ATPase subunit with a consequent enhanced intracellular concentration of doxorubicin in MDA-MB-231 and T47D cells. In conclusion, quercetin, despite its potent vascular protective activity against doxorubicin, was found to influence doxorubicin-induced antibreast cancer effects via pharmacodynamic as well as cellular pharmacokinetic aspects

Hepatoprotective effect of pentoxifylline against D-galactosamine-induced hepatotoxicity in rats

The present study was conducted to investigate effect of pentoxifylline (PTX) on acute liver injury caused by galactosamine (D-Gal) in rats and the underlying mechanism involved in this setting. Moreover, we attempted to compare its effect to the well-established hepatoprotective agent, silymarin (SYM). The rats were randomly assigned 5 groups, control, PTX-treated (100 mg/kg, 3 weeks), SYM-treated (100 mg/kg, 3 weeks) and their combination. Hepatic injury was induced by intraperitoneal single dose injection of D-Gal (800 mg/kg). Hepatic functions parameters, including serum albumin and alkaline phosphatase (ALP) levels were determined. Antioxidants enzyme activities such as superoxide dismutase (SOD), catalase (CAT) as well as lipid peroxides and hepatic total nitrites were measured. Besides, histopathological examination was also performed using portions of liver tissues. Results showed that the liver injury induced by D-Gal was improved in the three pretreated groups to variable extents. Pretreatment with PTX prevented D-Gal-induced reduction of antioxidante enzyme activities, SOD and CAT, and attenuated the elevated malonaldahyde (MDA) level in hepatic tissue as marker of lipid peroxidation. In addition, pretreatment with PTX resulted in an increase in hepatic triglycerides, normalization of nitric oxide level, and lowering serum ALP activity as well as inhibited the decreased serum albumin level caused by D-Gal. These biochemical changes were reflected on attenuation the structural alterations of the liver integrity. Collectively, our data suggest that PTX exhibits a potential hepatoprotective effect against D-Gal-induced hepatotoxicity and this effect might be attributed to its antioxidant properties

Purification and characterization of pectin methylesterase isoenzymes from orange peel

No Abstract. The Egyptian Journal of Biochemistry and Molecular Biology Vol. 24(1) 2006: 73-9