Phosphoinositide 3-kinase (PI3K) is an enzyme that mediates endocrinological responses, such as intracellular signaling of insulin and growth factors, and plays important roles in muscle homeostasis and growth. In this study, the effect of antemortem PI3K activity on meat quality traits was investigated using broiler chickens whose PI3K was inhibited pharmacologically. Breast and thigh muscles were harvested from broilers treated with the PI3K inhibitor wortmannin, and meat quality traits were evaluated by determination of color, water-holding capacity, and breaking strength. The pH and concentrations of glycogen and free amino acids were also investigated as determinants of the chemical properties of meat. The results indicated that antemortem PI3K inhibition by wortmannin modified breast muscle color with lower L∗ values (P < 0.05) and b∗ values (P < 0.05) and higher a∗ values (P < 0.05). Antemortem PI3K inhibition also increased the water-holding capacity of breast muscles (P < 0.05), although breaking strength was not much affected. In addition, antemortem PI3K inhibition increased the concentrations of free amino acids in breast muscles, especially arginine (P < 0.05) and glutamic acid (P < 0.05). Similar effects were observed in thigh muscles. Lower glycogen levels at sacrifice (P < 0.05) and the resultant higher pH during the postmortem period (P < 0.05) were associated with PI3K inhibition–induced changes in meat quality traits. The wortmannin-treated muscles shared certain features with dark, firm, and dry meat which is a common abnormal meat. These findings suggest that antemortem PI3K activity contributes to meat quality traits and is involved in the molecular mechanism of the production of meat quality abnormalities.

磷酸肌醇 3-激酶 (PI3K) 是一种介导内分泌反应的酶，例如胰岛素和生长因子的细胞内信号传导，在肌肉稳态和生长中起重要作用。在这项研究中，使用药理学抑制 PI3K 的肉鸡研究了生前 PI3K 活性对肉质性状的影响。从用 PI3K 抑制剂 wortmannin 处理的肉鸡身上采集胸部和大腿肌肉，并通过测定颜色、持水性和断裂强度来评估肉质性状。还研究了糖原和游离氨基酸的 pH 值和浓度作为肉类化学性质的决定因素。结果表明，wortmannin 对生前 PI3K 的抑制作用改变了乳房肌肉的颜色，具有较低的 L* 值（P < 0.05) 和 b∗ 值 ( P < 0.05) 和更高的 a∗ 值 ( P < 0.05)。Antemortem PI3K抑制也增加了乳房肌肉的保水能力（P <0.05），虽然断裂强度没有太大影响。此外，生前PI3K抑制增加了胸肌中游离氨基酸的浓度，尤其是精氨酸（P < 0.05）和谷氨酸（P < 0.05）。在大腿肌肉中观察到类似的效果。处死时较低的糖原水平 ( P < 0.05) 并导致死后期间较高的 pH 值 ( P< 0.05) 与 PI3K 抑制诱导的肉质性状变化有关。经渥曼青霉素处理的肌肉与深色、紧实和干燥的肉具有某些特征，这是一种常见的异常肉。这些发现表明，生前 PI3K 活性有助于肉质性状，并参与肉质异常产生的分子机制。