Effect of alpha-lipoic acid on relieving ammonia stress and hepatic proteomic analyses of broilers.

Ammonia in poultry houses not only affects worker health but also induces a variety of poultry diseases. Alpha-lipoic acid (LA) is an effective antioxidant that protects cells against oxidative injury during various toxic and pathological processes. This study was designed to evaluate the mitigating effects of LA supplementation on ammonia stress and hepatic proteome changes in broilers. Male broilers (22 d old) were allocated to 3 groups: (1) a control group without ammonia stress (CTRL); (2) exposure to 70 ppm ammonia (AM); and (3) exposure to 70 ppm ammonia and dietary administration of 300 mg/kg LA (AM+LA). Ammonia exposure significantly decreased broiler growth performance and plasma glutathione peroxidase activity (P < 0.05), and increased plasma malondialdehyde content and glutamic-pyruvic transaminase activity (P < 0.05). These negative effects were eliminated by LA supplementation. Comparative proteomic analyses revealed 291 differentially expressed proteins in the AM group compared to the CTRL and AM+LA groups. A total of 30 proteins were differentially expressed between the AM/CTRL and (AM+LA)/AM groups. The addition of LA restored 24 of these proteins to control levels; these proteins were mainly related to transcription regulation, detoxification, protein translation and degradation, and immune and stress responses. The differentially expressed proteins included the high mobility group box (HMGB) and glutathione S-transferase (GST), which is closely related to immune response and oxidative stress, and collagens, which are implicated in liver injury. The addition of LA to broiler diet may reduce ammonia toxicity by maintaining the antioxidant system, xenobiotic metabolism, and metabolic pathways.

Long-lasting infiltration anaesthesia by lidocaine-loaded biodegradable nanoparticles in hydrogel in rats.

BACKGROUND: Infiltration of a long-lasting anaesthetic is helpful during the post-operative period. The recently developed local drug delivery system, biodegradable nanoparticles in a thermo-sensitive hydrogel (nanogel system), may possibly provide an extended duration of drugs. Therefore, we evaluated whether prolonged infiltration anaesthesia could be achieved by loading lidocaine into this delivery system. METHODS: Thirty male rats were randomized into five groups of six rats each: saline; 2% hydrochloride lidocaine solution; lidocaine-loaded nanogel system and its compositing formulations, namely lido-nano gel; lido-nano; and lidogel. Durations of local anaesthesia with subcutaneously injected agents were measured by tail flick latency tests in a randomized, blind fashion. RESULTS: Lido-nano gel produced effective anaesthesia for 360+/-113 min, compared with 150+/-33 min by lidogel, 180+/-37 min by lido-nano, and 110+/-45 min by lidocaine solution (P<0.001, means+/-SD), and elicited complete sensory blockade for 300+/-114 min, compared with 75+/-37 min by lidogel, 105+/-53 min by lido-nano, and 60+/-33 min by lidocaine solution (P<0.001, means+/-SD) without severe skin/systemic toxicity. CONCLUSION: Lidocaine-loaded biodegradable nanoparticles in hydrogel produced prolonged infiltration anaesthesia in rats without severe toxicity, indicating a possible way to develop long-lasting local anaesthetics.