In vitro toxicity of cinnamaldehyde and nanoemulsion of cinnamaldehyde on protoscoleces of hydatid cyst.

Cystic echinococcosis is a major parasitic and zoonotic disease and surgery is the most common treatment of this disease which carries the risk of intraoperative leakage and recurrence. Using scolicidal agent to inactivate cyst contents reduces the risk of recurrence. Considering side effects of available scolicidals and growing interests on natural pharmaceuticals, the present study aimed to evaluate toxicity of cinnamaldehyde (CA), the main component of cinnamon essential oil, and a developed nanoemulsion of cinnamaldehyde (nano-CA) on protoscoleces of hydatid cyst. Nanoemulsion was prepared by the low energy system and characterized by dynamic light scattering to confirm dimensions. For evaluation of scolicidal effects, serial dilutions of CA and nano-CA were mixed with protoscolices suspension and mortality were recorded at 10, 30, and 60 minutes by eosin exclusion test. Albendazole was used as the positive control. The mean diameter of nano-CA was characterized as equal to 88.5 nm, and poly dispersity index was 0.09. After 30 min of treatment, nano-CA, at 50 µg/ml, killed 99.33% of protoscoleces. At the same time point and concentration, CA only caused mortality rate of 26.18%. 30 min-LC50 value of 369.39 µg/ml was obtained for CA, while after 30 min of exposure, nano-CA showed promising rapid activity with LC50 value of 3.22 µg/ml. Nano formulation significantly increased scolicidal activity of CA probably by increasing penetration and tegumental disorganization of protoscoleces. Further in vivo safety studies are needed to introduce nano-CA as a clinically applicable scolicidal agent.

Importance of Connexin-43 based gap junction in cirrhosis and acute-on-chronic liver failure.

BACKGROUND & AIMS: In cirrhosis, superimposed inflammation often culminates in acute-on-chronic liver failure (ACLF) but the mechanism underlying this increased sensitivity is not clear. Cx43 is a ubiquitous gap junction protein that allows transmission of signals between cells at a much higher rate than the constitutively expressed gap junctions. The aims of the study were to test the hypothesis that inflammation drives the increased expression of hepatic Cx43 and to determine its role by Cx43 inhibition. METHODS: Four weeks after bile-duct ligation (BDL) or sham operation, rats were treated with an anti-TNF antibody, or saline; with or without LPS (1mg/kg); given 3h prior to termination. Biochemistry and cytokines were measured in the plasma and hepatic protein expression (NFkB, TNFα, iNOS, 4HNE, Cx26, 32, and 43) and confocal microscopy (Cx26, 32, and 43) were performed. The effect of a Cx43-specific inhibitory peptide was studied in a mouse BDL model. RESULTS: BDL animals administered LPS developed typical features of ACLF but animals administered infliximab were relatively protected. Cx26/32 expression was significantly decreased in BDL animals while Cx43 was significantly increased and increased further following LPS. Infliximab treatment prevented this increase. However, inhibiting Cx43 in BDL mice produced detrimental effects with markedly greater hepatocellular necrosis. CONCLUSIONS: The results of this study show for the first time an increased expression of hepatic Cx43 in cirrhosis and ACLF, which was related to the severity of inflammation. This increased Cx43 expression is likely to be an adaptive protective response of the liver to allow better cell-to-cell communication.

Characterization of occult hepatitis B virus strains in South African blood donors.

UNLABELLED: Since October 2005, all blood units collected in South Africa were screened individually for human immunodeficiency virus (HIV)-1, hepatitis B and C virus (HBV, HCV) genomes uncovering preseroconversion window period (WP) infections for each virus and occult HBV infections (OBIs) defined as persistent HBV DNA without detectable hepatitis B surface antigen (HBsAg). Samples identified as HBsAg-negative/DNA-positive were confirmed by combining real-time quantitative polymerase chain reaction, nested amplification, anti-HBc and anti-HBs. Amplified basic core promoter/precore, pre-S/S, and whole genome were sequenced, analyzed, and compared to 73 HBsAg+ strains. Genotype was determined by phylogenetic analysis. From 109 samples examined, 54 were classified as OBI, 14 as WP, 20 as false-positive, five as other classification, and 16 as undetermined due to lack of serological or follow-up data. OBI donors were predominantly males (67%), median age 31 years, black (54%), with normal alanine aminotransferase levels. Viral load ranged between unquantifiable and 518 IU/mL (median 5 IU/mL). Genotype A1 was more frequent (23 strains) than genotype D (seven strains). Genotype A1 strains were little mutated. In the major hydrophilic region, 56.5% strains were wild type or with few amino acid substitutions. Most important, all 13 full genome sequences presented 1 to 7 mutations known to or assumed to negatively impact viral replication. In particular, 6/13 sequences had a stop codon in the HBx gene translated into deletion of 117 or 19-25 C-terminus amino acids not found in 15 HBeAg+ HBsAg+ strains. One WP sequence with an HBx stop codon suggested infectivity. CONCLUSION: Genotype A1 OBIs are different from genotype A2 and D OBIs in that there is little evidence of immune pressure as a major factor involved in OBI genesis. Limited replication appears mostly related to genetic viral defects.

Characterization of occult hepatitis B virus from blood donors carrying genotype A2 or genotype D strains.

BACKGROUND/AIMS: Nucleic acid testing (NAT) for hepatitis B virus (HBV) DNA in blood donations identified occult HBV infection (OBI) as a potential threat to blood safety. METHODS: A collaborative study was undertaken to explore the molecular basis of OBIs prevalent in Europe in relation to clinical and serological data. RESULTS: Ninety-one percent of 77 donor samples of European origin HBV DNA positive but HBV surface antigen (HBsAg) negative were confirmed. Viral load ranged between unquantifiable and 5640 IU/mL (median 25 IU/mL). Fifty-two strains were genotyped (14 HBV(A2) and 38 HBV(D)). Compared to HBsAg+ samples, genotype D was significantly more frequent than genotype A2 in OBIs from Poland or Italy (P<0.04). Amino acid substitutions were concentrated in the immunologically active parts of the Pre-S/S proteins (P<0.0001) affecting both cellular CD8 T-cell epitopes and B-cell neutralizing Major Hydrophilic Region epitopes. Substitutions were more frequent in OBIs than in HBsAg+ strains of both genotype D (P<0.001) and A2 (P<0.01), in OBIs of genotype D than A2 in the 'a' region (P<0.001) but not cellular epitopes, and in anti-HBs+ than anti-HBs- OBIs (P<0.001). CONCLUSIONS: Results support the hypothesis that humoral and cellular immune pressure on the HBV envelope proteins are major mechanisms generating OBI.