18S rRNA gene sequencing for environmental aflatoxigenic fungi and risk of hepatic carcinoma among exposed workers.

Aspergillus exposure causes an increase in aflatoxin (AF) levels among exposed workers thereby increasing their risk of developing hepatocellular carcinoma (HCC). This study attempted to determine the presence of airborne aflatoxigenic fungi in environment of waste water treatment plant (WWTP); and study the hepatic cancer risks among exposed workers, emphasizing the role of glutathione S-transferases (GST) gene polymorphism protecting against the risk of hepatic cancer development due to exposure to AFs. The study isolated and identified different Aspergillus species producing AFs in air samples from WWTP sites using 18S ribosomal ribonucleic acid (18S rRNA) gene sequencing technique. GST gene polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A significant increase in blood AF levels was found among WWTP exposed workers. The occurrence of GSTT1& M1 gene polymorphism in 6% of the workers was accompanied by significant decrease in the levels of AFs and alpha fetoprotein (AFP). In conclusion, Aspergillus-producing AFs were found in air of WWTP. Continuous exposure to AF-producing fungi caused elevated AF-levels in exposed workers. However only workers with heterozygous GSTT1& M1 genotypes can detoxify AFs, thereby decreasing the risk of HCC development among exposed workers.

Antibacterial effect of the red sea soft coral Sarcophyton trocheliophorum.

The marine soft corals Sarcophyton trocheliophorum crude extracts possessed antimicrobial activity towards pathogenic bacterial strains, i.e. Bacillus cereus, Salmonella typhi, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Bioassay-guided fractionation indicated that the antimicrobial effect was due to the presence of terpenoid bioactive derivatives. Further biological assays of the n-hexane fractions were carried out using turbidity assay, inhibition zone assay and minimum inhibitory concentration for investigating the growth-inhibition effect towards the Gram-positive and Gram-negative bacteria. The fractions were screened and the structure of the isolated compound was justified by interpretation of the spectroscopic data, mainly mass spectrometry (GC-MS). The structure was assigned as (5S)-3-[(3E,5S)-5-hydroxy-3-hepten-6-yn-1-yl]-5-methyl-2(5H)-furanone and was effective at concentrations as low as 0.20 mg/mL. The above findings, in the course of our ongoing research on marine products, may implicate that the profound anti-microbial activity of the S. trocheliophorum soft corals, inhabiting the red sea reefs, is attributed to the presence of growth-inhibiting secondary metabolites mainly terpenoids.

Effect of carnosine on gentamicin-induced nephrotoxicity.

BACKGROUND: Gentamicin (GM) is an antibiotic whose clinical use is limited by its nephrotoxicity. Thus the present study was undertaken to investigate if carnosine, an antioxidant, could protect the kidney in this experimental model. MATERIAL/METHODS: The animals were divided into seven groups each of 10 animals: one control group, two healthy carnosine groups (10 mg/kg/day), two GM groups (80 mg/kg/day), and two carnosine-GM groups. Kidney function tests, histopathological, ultrastructural, and enzymatic histochemical studies clarified GM nephrotoxicity. RESULTS: GM rat showed early kidney function failure as blood creatinine and blood urea were significantly increased after one and two weeks. Experimental evidence suggested a role of reactive oxygen species in GM-induced nephrotoxicity. Histopathological examination revealed degenerative changes in glomeruli and tubules. Ultrastructural study showed glomerular changes, some degeneration of both distal and collecting tubules. The proximal tubules showed marked degrees of changes and necrosis. Enzymatic histochemical studies of GM rats revealed marked elevation of lactate dehydrogenase (LDH) and inhibition of succinic dehydrogenase (SDH), alkaline phosphatases (ALP), acid phosphatases (ACP), and adenosine triphosphatase (ATPase). Blood creatinine and urea were normalized in the carnosine-GM group after one and two weeks. Structural and enzymatic histochemical pictures were greatly ameliorated. CONCLUSIONS: The mechanism by which carnosine has a protective effect on GM-induced nephrotoxicity was attributed to its many actions: double antioxidant action, protein molecule protection, removal of harmfully modified ones, activation of immune system, preservation of membrane fluidity, and cytosolic buffering. Carnosine thus offers a promise of ameliorating GM nephrotoxicity.

Biochemical modifications induced in rabbits by Schistosoma mansoni antigens and the beneficial effect of carnosine treatment.

This immunological study involved individual injection of the three Schistosoma mansoni antigens (Ags). soluble egg antigen (SEA), cercarial antigen preparation (CAP) or soluble worm antigen preparation (SWAP) in three rabbits groups (Ag). respectively. Three other groups each received the same specific antigen conjoined with administration of L-carnosine (Ag-C). Determination of three hepatic parameters and ten serum proteins was done. These were total protein, glycogen content and glycogen phosphorylase b activity of liver as well as serum total protein and nine protein fractions [alpha2-macrglobulin; beta-galactosidase; phosphorylase b; serum albumin; fumarase; carbonic anhydrase; beta-lactoglobulin; alpha-lactalbumin and aprotinin]. Conjoined carnosine treatment produced numerous variations. SEA-I-C group presented sex decreased parameters. In CAP-I-C animals hepatic glycogen content was increased while phosphorrylase b activity was decreased as well as seven the concentration of serum parameters; total serum protein, alpha2-macroglobulin, phosphorylase b, albumin, fumarase, carbonic anhydrase, alpha-lactalbumin and aprotinin. In SWAP-I-C group the concentration of only one fraction was decreased; carbonic anhydrase. In batch A both the Ags. of the egg and cercaria, developmental stages having transient residence in the animal host, showed more affection by the specific Ag. Although, carnosine modified the results of all the three groups in batch B yet, its effect on both the egg and cercaria Ags. was still more than that of worm.

Effect of carnosine administration on the immune response of rabbit to Schistosoma mansoni antigens.

SDS-PAGE separation of soluble worm antigen preparation (SWAP), cercarial antigen preparation (CAP), and soluble egg antigen (SEA) of Schistosoma mansoni showed obvious qualitative and quantitative differences. The shared polypeptides of the three stages of S. mansoni were 116, 72.768 and 32.367 kDa under reducing conditions. The different anti-sera raised in rabbits against the different stages of antigens were recognized by electroimmune transfer blotting (EITB). Each of the 3 groups separated eight bands. Carnosine treatment of rabbits immunized with SWAP, CAP or SEA resulted in the disappearance of two bands in SWAP group and one band in CAP group in comparison with the non-treated immunized groups. This indicated that the carnosine modulated immune response of rabbits against S. mansoni antigens.

Effects of carnosine on bilharzial infestation in hamsters: biochemical and histochemical studies.

We tested the ability of carnosine to improve some liver disorders induced by Schistosoma mansoni parasite in hamsters (Mesocricetus auratus). Results indicate that parasitic infestation induced elevation in serum alkaline phosphatase, gamma-glutamyl transferase, aspartate aminotransferase and procollagen III peptide as a marker of liver fibrosis. Administration of carnosine (10 mg/day) for 15 days either concurrent with infection, 2 and 4 weeks post-infestation was effective in reducing differential worm burden. It was also effective in renormalizing blood glucose level depending on the time course. The most evident effect of carnosine was on serum procollagen III peptide level, which was lowered in infested groups treated with carnosine. Histopathological studies confirmed the potential use of carnosine for intervention in schistosomiasis.