RESUMO
The objective of this study was to observe the effects of selenium-yeast (SY) on growth performance, muscle antioxidant activity, meat quality, fatty acid and amino acid profiles in growing goats. A total of 18 Qianbei-pockmarked goats were assigned to three groups (six duplicates per group) by body weight (25.75 ± 1.75 kg; mean ± standard deviation) according to a completely randomized design: (1) basal diet (CON); (2) CON with 2.4 mg/kg SY (LS); and (3) CON with 4.8 mg/kg SY (HS). The results indicated that goats receiving SY did not show any differences (P > 0.05) in terms of dry matter intake, growth performance, or muscle chemical composition. In addition, dietary treatment did not affect (P > 0.05) the pH values (pH45min and pH24h), percentage of water loss, drip loss, or cooking loss. The HS group showed a significant increase (P < 0.05) in the dressing percentage, eye muscle area and meat color, as well as muscle total antioxidant capacity, glutathione peroxidase and 2,2-diphenyl-1-picrylhydrazyl scavenging activity levels, whereas it showed a significant drop (P < 0.05) in shear force and muscle malondialdehyde levels relative to the control. Feeding 4.8 mg/kg SY led to a significant (P < 0.05) decrease in the levels of C8:0, C14:0, C15:0, C16:0, C17:0, C18:0, C20:0 and total saturated fatty acids, whereas it led to a significant (P < 0.05) increase in C15:1 in comparison with that of the control group. Goats receiving 2.4 mg/kg SY had significantly (P < 0.05) increased C16:1, C17:1, C18:1n7, C18:2n6, C18:3n3, C20:4n6, C22:1n9, and PUFA relative to the control group. Compared with the control group, the treatment groups had higher (P < 0.05) levels of C18:1n9, C22:4, and monounsaturated fatty acids. The inclusion of 2.4 mg/kg SY induced significant (P < 0.05) increases in 4-aminobutyric acid, glutamic acid and umami amino acid concentrations compared to the control. In addition, the feeding of 4.8 mg/kg SY had significantly higher (P < 0.05) muscle serine, valine, isoleucine, leucine, ornithine hydrochloride, methionine, and tyrosine levels than the control group. Collectively, Se supplementation in the diet did not affect growth performance, muscle chemical composition, whereas it could improve meat quality, muscle antioxidant activity, fatty acid and amino acid profiles in Qianbei-pockmarked goats. This showed that the optimal accession SY level was 4.8 mg/kg under the experimental conditions of this study.
RESUMO
Tissue injury is known to produce inflammation and pain. Synaptic potentiation between peripheral nociceptors and spinal lamina I neurons has been proposed to serve as a trigger for chronic inflammatory pain. Gastrodin is a main bioactive constituent of the traditional Chinese herbal medicine Gastrodia elata Blume, which has been widely used as an analgesic since ancient times. However, its underlying cellular mechanisms have remained elusive. The present study demonstrated for the first time that gastrodin exhibits an analgesic effect at the spinal level on spontaneous pain, mechanical and thermal pain hypersensitivity induced by peripheral inflammation, which is not dependent on opioid receptors and without tolerance. This analgesia by gastrodin is at least in part mediated by depressing spinal synaptic potentiation via blockade of acid-sensing ion channels. Further studies with miniature EPSCs and paired-pulse ratio analysis revealed the presynaptic origin of the action of gastrodin, which involves a decrease in transmitter release probability. In contrast, neither basal nociception nor basal synaptic transmission was altered. This study revealed a dramatic analgesic action of gastrodin on inflammatory pain and uncovered a novel spinal mechanism that could underlie the analgesia by gastrodin, pointing the way to a new analgesic for treating chronic inflammatory pain.
