Dietary selenium supplementation prolongs pentobarbital induced hypnosis

Antiviral drug disposition and natural health products: risk of therapeutic alteration and resistance

The HIV/AIDS patient population is known to use natural health products (NHPs) in addition to the several antiretroviral drugs that constitute the treatment regimen for this disease. This review focuses on NHPs and their potential for interactions with antiretroviral agents resulting in therapeutic alterations or resistance. There are conflicting published medical literature reports and very few well-documented human clinical studies that unequivocally demonstrate if this concomitant use increases the risk of interaction/adverse reaction with these therapeutic products. This article outlines some findings from the Canadian domestic adverse reaction case reports associated with the use of antiretrovirals and NHPs. These adverse reaction case reports were specifically examined for patients taking NHPs together with their highly active antiretroviral therapy during or around the time when the adverse reaction developed. Together, the case reports and limited human clinical studies suggest that the risk for therapeutic alterations and resistance can exist due to changes in pharmacokinetic parameters with concomitant use of these therapeutic products.

Synergistic action of sodium selenite and N-acetylcysteine in acetaminophen-induced liver damage

Acetaminophen (AAP) is a commonly used analgesic and antipyretic drug; however, when used in high doses, it causes fulminant hepatic necrosis in both humans and experimental animals. In this study, we investigated whether selenium (Se) and N-acetylcysteine (NAC), alone or in combination, are protective against AAP toxicity in mice. At the beginning of the experiment, blood samples were taken from 10 of 350 mice. Then, the remaining mice were randomly allocated into four groups, each consisting of 35 animals. The 1st group received a single administration of AAP by gavage at a dose of 600 mg/kg-bw, p.o. The 2nd group (AAP-Se) was treated with sodium selenite (0.5 mg Se/kg-bw, p.o.) one hour after ingestion of AAP. The 3rd group (AAP-NAC) ingested AAP, 1.5 h later followed by NAC (500 mg/kg-bw, p.o.). The 4th group (AAP-Se-NAC) was given sodium selenite and NAC, 1 and 1.5 h after administration of AAP, respectively. From each group, blood samples of seven mice for each time point were taken at 4, 8, 24, and 48 h after AAP toxicity. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) levels were measured. Compared with AAP group, the levels of ALT were lower after AAP ingestion in AAP-NAC, AAP-Se, and AAP-Se-NAC groups at the 8th hour. ALT, AST, and LDH levels in AAP-Se-NAC group were 50% of the levels of other groups starting form the 4th hour of toxicity. It is concluded that protection against AAP hepatotoxicity using a combination of Se and NAC is better than that found with either agent alone.

mRNA expression in mouse hypothalamus and basal forebrain during influenza infection: a novel model for sleep regulation

After influenza infection, C57BL/6J mice develop increased slow-wave sleep (SWS) during the dark phase of the day-night cycle, whereas BALB/cByJ mice develop decreased SWS during the light phase. A previous analysis of CXB recombinant inbred mice revealed a quantitative trait locus (QTL) designated Srilp (sleep response to influenza, light phase) that was related to expression of the BALB/cByJ sleep phenotype. Srilp was localized to the 10- to 12-cM region of mouse Chr 6 between D6Mit74 and D6Mit188. Temt (thioether S-methyltransferase), which is located at region B3 of Chr 6, is a potential candidate gene for Srilp. We evaluated the expression of Temt and other Srilp candidate genes in hypothalamus and basal forebrain of uninfected and influenza-infected C57BL/6J and BALB/cByJ mice. We report here that Temt expression varies significantly with respect to mouse strain, health status, brain region, and day-night phase. C57BL/6J mice show day-night variation in Temt expression in hypothalamus, but BALB/cByJ mice do not. Temt expression in basal forebrain is much higher in C57BL/6J mice than in BALB/cByJ mice. During influenza infection, both C57BL/6J and BALB/cByJ mice show reduced Temt mRNA in basal forebrain at 30 h postinoculation, but expression remains much lower in the BALB/cByJ strain. In contrast, prostaglandin-d-synthase ( Ptgds) and lipocalin 2 ( Lcn2) mRNA increase in basal forebrain of both strains after influenza infection. Administration of the TEMT inhibitor sinefungin reduces sleep in uninfected BALB/cByJ mice and attenuates influenza-induced sleep enhancement in C57BL/6J mice. These data suggest that strain- and infection-related alterations in sleep may be influenced by Temt expression and perhaps by subsequent effects on prostaglandin metabolism.