BACKGROUND: Melatonin has demonstrated protective effects in severe sepsis/shock in the animal model. Zymosan A causes inflammation and shock leading to death in rats. We hypothesized that daily afternoon melatonin administration would improve rat survival after an intraperitoneal (IP) zymosan injection. METHODS: Adult male rats, maintained on a 12L:12D photoperiod, received a single IP injection of either zymosan (500 mg/kg) or paraffin vehicle at 1200 hours. At 1700 hours and daily thereafter, zymosan-injected rats received subcutaneous injections of either melatonin (0.8 mg/kg) or saline (SAL). Any surviving animals were killed on day 10 to obtain wet organ weights. RESULTS: Three independent experiments produced similar results. In each zymosan+SAL group, all animals died by day 4. In the melatonin-treated groups combined, 33/45 rats survived (73.33%, P<.00002). Posthumous body weight was greater in melatonin-treated animals compared with the zymosan+SAL groups (P<.001). Mean splenic weight in the melatonin-treated groups was twice that of the control groups (P<.001). CONCLUSION: Melatonin administered in the late afternoon after a lethal dose of zymosan significantly improved animal survival. Melatonin has no known adverse effects in humans and may represent a novel treatment for sepsis/shock.
BACKGROUND:Melatonin has demonstrated protective effects in severe sepsis/shock in the animal model. Zymosan A causes inflammation and shock leading to death in rats. We hypothesized that daily afternoon melatonin administration would improve rat survival after an intraperitoneal (IP) zymosan injection. METHODS: Adult male rats, maintained on a 12L:12D photoperiod, received a single IP injection of either zymosan (500 mg/kg) or paraffin vehicle at 1200 hours. At 1700 hours and daily thereafter, zymosan-injected rats received subcutaneous injections of either melatonin (0.8 mg/kg) or saline (SAL). Any surviving animals were killed on day 10 to obtain wet organ weights. RESULTS: Three independent experiments produced similar results. In each zymosan+SAL group, all animals died by day 4. In the melatonin-treated groups combined, 33/45 rats survived (73.33%, P<.00002). Posthumous body weight was greater in melatonin-treated animals compared with the zymosan+SAL groups (P<.001). Mean splenic weight in the melatonin-treated groups was twice that of the control groups (P<.001). CONCLUSION:Melatonin administered in the late afternoon after a lethal dose of zymosan significantly improved animal survival. Melatonin has no known adverse effects in humans and may represent a novel treatment for sepsis/shock.
Authors: Eleni N Sertaridou; Ioanna G Chouvarda; Konstantinos I Arvanitidis; Eirini K Filidou; George C Kolios; Ioannis N Pnevmatikos; Vasilios E Papaioannou Journal: Ann Intensive Care Date: 2018-12-04 Impact factor: 6.925
Authors: Antonio Carrillo-Vico; Patricia J Lardone; Nuria Alvarez-Sánchez; Ana Rodríguez-Rodríguez; Juan M Guerrero Journal: Int J Mol Sci Date: 2013-04-22 Impact factor: 5.923