Department of Pediatrics, Vittore Buzzi Children's Hospital, University of Milan, 20154 Milan, Italy.
Institute of Biomedical Technologies, National Research Council, 20090 Segrate, Italy.
Nutrients. 2022 Apr 29;14(9):1883. doi: 10.3390/nu14091883.
Glycomacropeptide (GMP) represents a good alternative protein source in Phenylketonuria (PKU). In a mouse model, it has been suggested to exert a prebiotic role on beneficial gut bacteria. In this study, we performed the 16S rRNA sequencing to evaluate the effect of 6 months of GMP supplementation on the gut microbiota of nine PKU patients, comparing their bacterial composition and clinical parameters before and after the intervention. GMP seems to be safe from both the microbiological and the clinical point of view. Indeed, we did not observe dramatic changes in the gut microbiota but a specific prebiotic effect on the butyrate-producer spp. and, to a lesser extent, of . Clinically, GMP intake did not show a significant impact on both metabolic control, as phenylalanine values were kept below the age target and nutritional parameters. On the other hand, an amelioration of calcium phosphate homeostasis was observed, with an increase in plasmatic vitamin D and a decrease in alkaline phosphatase. Our results suggest GMP as a safe alternative in the PKU diet and its possible prebiotic role on specific taxa without causing dramatic changes in the commensal microbiota.
甘氨酰脯氨酸二肽（GMP）是苯丙酮尿症（PKU）患者的一种优质替代蛋白来源。在小鼠模型中，它被认为对有益肠道细菌具有益生元作用。在这项研究中，我们对 9 名 PKU 患者进行了 16S rRNA 测序，以评估 GMP 补充 6 个月对肠道微生物群的影响，比较了干预前后的细菌组成和临床参数。GMP 从微生物学和临床角度来看似乎是安全的。事实上，我们没有观察到肠道微生物群的剧烈变化，但对丁酸产生菌 spp. 和 产生了特定的益生元作用，在较小程度上对 也有一定作用。临床上，GMP 摄入对代谢控制没有显著影响，因为苯丙氨酸值保持在年龄目标以下，且营养参数也没有变化。另一方面，观察到钙磷稳态得到改善，血浆维生素 D 增加，碱性磷酸酶减少。我们的研究结果表明，GMP 作为 PKU 饮食的一种安全替代物，可能对特定分类群具有益生元作用，而不会引起共生微生物群的剧烈变化。
