Nucleoside-nucleotide Mixture Research Articles

Protection of BALB/c mice against methicillin-resistant Staphylococcus aureus infection by intraperitoneal administration of nucleoside-nucleotide mixture.

The effect of intraperitoneally administered nucleic acid components (nucleoside-nucleotide mixture) on the recovery from methicillin-resistant Staphylococcus aureus (MRSA) strain 8985N infection was studied in mice. Two experiments were conducted in which BALB/c mice were fed a nucleotide-free 20% casein diet for 30 days. On the 10th day, the mice were inoculated intravenously with viable MRSA organisms. The mice were intraperitoneally administered nucleoside-nucleotide mixture or saline (control) daily from the onset of the experiment (experiment 1) or from the day of inoculation (experiment 2). The survival rate in the nucleoside-nucleotide group in experiment 1 (70%) was significantly higher than that in the saline group (20%) (p < 0.05). In experiment 2, the survival rate in the nucleoside-nucleotide group (55%) tended to be higher than that in the saline group (36%) without statistically significant difference; furthermore, in the surviving mice, the viable MRSA organisms recovered from the spleen and the kidney were fewer in the former group than in the latter group (p < 0.05). The studies showed that the intraperitoneal administration either before or after the MRSA challenge of the nucleoside-nucleotide mixture was effective for the recovery of the mice from the infection.

A Mixture of Nucleosides and a Nucleotide Alters Hepatic Energy Metabolism 24 Hours after Hepatectomy in Rabbits

The effect of administering a nucleoside-nucleotide mixture on hepatic energy metabolism was evaluated at 24 h after hepatectomy in rabbits that had had 70% of their livers removed. After hepatectomy, animals were administered continuous intravenous infusion of 2 mL/(kg body wt-h) of 9 g/L NaCl (Group S), 5.99 mmol/L nucleoside-nucleotide mixture (Group N1) or 11.98 mmol/L nucleoside-nucleotide mixture (Group N2). At 24 h after hepatectomy, the hepatic adenylate energy charge in Group S (0.83 ± 0.01, mean ± SEM) was significantly lower than that before hepatectomy (0.90 ± 0.01). By contrast, the values in Groups N1 and N2 after hepatectomy (0.74 ± 0.04 and 0.73 ± 0.04, respectively) were significantly lower than that in Group S. The hepatic mitochondrial phosphorylation rate before hepatectomy was 46.40 ± 4.88 nmol ATP/(mg mitochondrial protein-min). After hepatectomy, significantly greater values were observed in Groups N1 and N2 (69.53 ± 7.20 and 63.31 ± 6.11, respectively), yet those values were less than observed in Group S (109.14 ± 4.80). These results suggest that the nucleoside-nucleotide mixture suppressed the enhancement of hepatic mitochondrial phosphorylative activity at a time when hepatic adenylate energy charge is compromised. Such enhancement is needed to compensate for the increased energy expenditure due to surgical intervention.

Effect of intraperitoneally administered nucleoside-nucleotide on the recovery from methicillin-resistant Staphylococcus aureus strain 8985N infection in mice.

The effect of intraperitoneally administered nucleoside-nucleotide on the recovery from methicillin-resistant Staphylococcus aureus (MRSA) strain 8985N infection was studied in mice. Mice fed nucleic acid-free 20% casein diet were administered intraperitoneally with a nucleoside-nucleotide mixture or with saline (control group) daily for 30 days. On the tenth day on this treatment, mice were challenged with the bacteria. The survival rates were 25% and 72% for the control and nucleoside-nucleotide groups, respectively. The recovery of the survived mice from the infection was confirmed by the increment of body weight and the reduction of the bacteria in the organs. The results show the effectiveness of the intraperitoneal administration of the nucleoside-nucleotide mixture for the recovery from the MRSA strain 8985N infection in mice.

Effects of total parenteral nutrition with nucleoside and nucleotide mixture on D-galactosamine-induced liver injury in rats.

The effect of a nucleoside-nucleotide mixture on liver injury of rats induced by D-galactosamine was studied by examining changes in function and histopathology of the liver. Animals with liver damage received total parenteral nutrition with glucose and amino acids supplemented with a nucleoside-nucleotide mixture containing inosine, cytidine, GMP, uridine and thymidine, or with uridine which inhibits galactosamine injury, or with liver cell extract containing flavin adenine dinucleotide and nucleic acid derivatives. As control, animals with liver damage received total parenteral nutrition with glucose and amino acids only. The serum GOT and GPT concentrations were significantly lower in the group supplemented with nucleoside-nucleotide mixture than those in other groups. A large dose (1.2 g/kg) of uridine inhibited liver injury, but a lower dose (0.14 g/kg) did not have any effect, whereas nucleoside-nucleotide mixture containing the same amount of uridine inhibited the injury. Liver cell extract also did not improve liver function. Thus infusion of a physiological and balanced mixture of nucleosides or nucleotides may improve liver function in rats with liver injury.