Mohamed A. Hamzawy

An Additional risk of Lung Cancer from Recurrent Exposure to EthylCarbamate (EC) in BALB/C Mice

Ethyl carbamate (EC); urethane is a chemical carcinogen (IARC group 2A). It has been commonly found in the fermented food and beverages. EC induced cancerous lesion in different sites due to the formation of active metabolite; vinyl carbamate (VC). The current study aims to investigate the potential risk of cancerous lesions in small and repeated exposure of ethyl carbamate in BALB/C mice. Three groups of BALBL/C mice were treated for 120 days included untreated control; group treated with a single dose of urethane (1.5 g/kg B.w/i.p) at a day one; group treated with repeated doses, the first at a day one and a second at day sixty (1.5g/ kg B.w/i.p). Ethyl carbamate (EC) exposure showed sever changes of serum biochemical markers, apoptosis markers, inflammatory cytokines as well as lipid peroxide formation in lung homogenate, these changes were pronounced in repeated exposure to ethyl carbamate. In addition, histological examinations revealed that epithelial changes in pulmonary tissues were advanced in animals treated with repeated doses of ethyl carbamate. These findings indicate that repeated exposure to ethyl carbamate of fermented foods and beverages is an additional risk for lung cancer due to permanent mitochondrial dysfunction and increase the cellular mitotic activity.

Transdermal delivery of vancomycin hydrochloride using combination of nano-ethosomes and iontophoresis: in vitro and in vivo study

Abstract This study aimed to evaluate transdermal delivery of vancomycin hydrochloride using the combination of ethosomes as an encapsulating vesicle and iontophoresis. Ethosomes were prepared and evaluated in terms of electrochemical stability. Cathodal iontophoresis of negatively charged ethosomes and anodal iontophoresis of free drug solution and positively charged vesicles were conducted. The effect of current mode, density, concentration of drug and ionic strength was studied. In vivo study was performed by inducing mediastinitis in Sprague-Dawley rats using methicillin-resistant Staphylococcus aureus as infected pathogen, the mean bacterial count was compared between groups of rats, one of the treated groups received drug intramuscularly while the other group received vancomycin using iontophoretic delivery of optimized ethosomal formula. Ethosomes showed efficient electrochemical stability, cathodal iontophoresis of negatively charged vesicle (F2) showed maximum transdermal flux (550 µg/cm2/h) compared to free drug solution and other ethosomal formulae, transdermal flux was reduced by altering current mode from continuous to ON/OFF mode, reducing current density and by using normal saline as drug solvent; on the other hand, flux was potentiated by increasing drug concentration from 25 to 75 mg/ml. In vivo study revealed that there was a significant difference in terms of bacterial count between untreated and treated groups, while there was no statistically significant difference between the I.M. vancomycin treatment and treatment conducted by iontophoretic delivery of vancomycin encapsulated in ethosomal formula. Combination between ethosomes and iontophoresis had succeeded in delivering vancomycin transdermally.

Dietary Supplementation of Calendula officinalis Counteracts the Oxidative Stress and Liver Damage Resulted from Aflatoxin

This study was conducted to evaluate the total phenolic compounds, the antioxidant properties, and the hepatorenoprotective potential of Calendula officinalis extract against aflatoxins (AFs-) induced liver damage. Six groups of male Sprague-Dawley rats were treated for 6 weeks included the control; the group fed AFs-contaminated diet (2.5 mg/kg diet); the groups treated orally with Calendula extract at low (CA1) and high (CA2) doses (500 and 1000 mg/kg b.w); the groups treated orally with CA1 and CA2 one week before and during AFs treatment for other five weeks. The results showed that the ethanol extract contained higher phenolic compounds and posses higher 1,1-diphenyl 1-2-picryl hydrazyl (DPPH) radical scavenging activity than the aqueous extract. Animals fed AFs-contaminated diet showed significant disturbances in serum biochemical parameters, inflammatory cytokines, and the histological and histochemical pictures of the liver accompanied by a significant increase in malondialdehyde (MDA) and a significant decrease in superoxide dismutase (SOD) and glutathione peroxidase (GPx) in liver. Calendula extract succeeded to improve the biochemical parameters, inflammatory cytokines, decreased the oxidative stress, and improved the histological pictures in the liver of rats fed AFs-contaminated diet in a dose-dependent manner. It could be concluded that Calendula extract has potential hepatoprotective effects against AFs due to its antioxidant properties and radical scavenging activity.

Antitumor activity of intratracheal inhalation of temozolomide (TMZ) loaded into gold nanoparticles and/or liposomes against urethane-induced lung cancer in BALB/c mice

Abstract The current study aimed to develop gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) as drug carriers for temozolomide (TMZ) and investigate the possible therapeutic effects of intratracheal inhalation of nanoformulation of TMZ-loaded gold nanoparticles (TGNPs) and liposome-embedded TGNPs (LTGNPs) against urethane-induced lung cancer in BALB/c mice. Physicochemical characters and zeta potential studies for gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) were performed. The current study was conducted by inducing lung cancer chemically via repeated exposure to urethane in BALB/C mice. GNPs and LGNPs were exhibited in uniform spherical shape with adequate dispersion stability. GNPs and LGNPs showed no significant changes in comparison to control group with high safety profile, while TGNPs and LTGNPs succeed to improve all biochemical data and histological patterns. GNPs and LGNPs are promising drug carriers and succeeded in the delivery of small and efficient dose of temozolomide in treatment lung cancer. Antitumor activity was pronounced in animal-treated LTGNPs, these effects may be due to synergistic effects resulted from combination of temozolomide and gold nanoparticles and liposomes that may improve the drug distribution and penetration.

Immunomodulatory and antimicrobial efficacy of Lactobacilli against enteropathogenic infection of Salmonella typhi: In-vitro and in-vivo study:

Salmonellosis-induced diarrhea, is one of the commonest cause of childhood mortality in developing countries. Using of probiotics is viewed as a promising means for reducing the pathogenic loads of bacterial infection. The current study aimed to evaluate the potential antimicrobial and immunomodulatory efficacy of isolated lactobacillus strains against the enteropathogenic effect of S. Typhi. Different Lactobacillus strains were isolated from 13 dairy products. Their antimicrobial activities were tested against different bacterial strains. Six groups of CD1 mice were treated for 8 days as follows: group (1) untreated control; group (2) was challenged with single inoculation S. typhi, and groups (3) and (4) were treated with Lactobacillus plantarum (LA5) or Lactobacillus paracsi (LA7) for 7 days, respectively. Groups (5) and (6) were challenged with S. typhi, and then treated with either LA5 or LA 7 for 7 days, respectively. Isolated Lactobacillus showed antimicrobial activity against wide range of bacterial strains. Salmonellosis showed high widal titer, induced significant disturbance of TNF and IL-1β, while sever changes of the histological patterns of the intestinal villi and hepatocytes have been illustrated. LA5 or LA7 succeeded to eradicate typhoid infection, restore the values of inflammatory cytokines to typical levels of control group, and improve histological pictures of intestinal and hepatic tissues. It can be concluded that lactobacilli are promising candidate in protection and eradication against bacterial infection induced by S. Typhi due to its antimicrobial, anti-inflammatory, and immunomodulatory activities.

Effects of natural compounds in treatment and prevention of hepatotoxicity and hepatocellular carcinoma

Liver diseases are most common disorders in the world and characterized by rapid changes from steatosis to chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Natural products that attained great attention is to be used in the prevention and treatment of multiple diseases in humans. Several researches have been reported numerous natural and phytochemical compounds that may counteract or prevent the hepatic injury and primary liver cancer. The conservative treatment of liver toxicity and HCC may face awkward challenges in chemotherapy such as therapeutic failure or drug resistance. Accordingly, there is an actual need for safe and effective therapeutic and preventive modalities for liver disorders. The present review aims to focus on the potential protective and therapeutic effects of natural compounds in the prevention and treatment of hepatotoxicity and HCC. It also demonstrates the mechanism of the natural products in enzymatic regulation of antioxidants and its role in apoptosis and proliferation of cancerous lesions of hepatocytes. Accordingly, it highlights the promising role of natural bioactive compounds and provides the rational for further transitional researches, and emphasize on the scientific validation of natural compounds for therapeutic portfolio for clinical use in liver diseases.