The present study aimed to evaluate the effects of the probiotic Lactobacillus rhamnosus GG (L.GG) on the serotonergic pathway in an animal model of peptic tryptic digested gliadin (PTG)-induced enteropathy that mimics celiac disease (CD). The serotonin (5-HT) levels, the gene expression and the protein contents of 5-HT_3B, 5-HTR₄ receptors, SERT and TPH1 were evaluated in the duodenal tissue samples of control and treated Wistar rats.

PTG caused an imbalance on both 5-HT receptors and SERT with a significant elevation of 5-HT levels, not due to increased synthesis by the TPH1. The L.GG counteracted the PTG-induced imbalance of the serotonergic system, reducing the 5-HTRs expression and increasing SERT without affecting TPH1 expression.

Further research, also performed in clinical trials, is required to understand the precise link between 5-HT and CD. Notwithstanding, by decreasing 5-HT levels, LGG may be a potential strategy for helping improve clinical symptoms of CD.

本研究旨在评估益生菌鼠李糖乳杆菌GG（L.GG）在消化性胰蛋白酶消化的醇溶蛋白（PTG）诱导的模仿乳糜泻（CD）的肠病动物模型中对血清素能途径的影响。在对照和治疗Wistar大鼠的十二指肠组织样品中评估5-HT，5-HT _3B，5-HTR ₄受体，SERT和TPH1的血清素水平，基因表达和蛋白质含量。

PTG导致5-HT受体和SERT均失衡，同时5-HT含量显着升高，这不是由于TPH1的合成增加。L.GG抵消了PTG诱导的5-羟色胺能系统的不平衡，降低了5-HTRs的表达并增加了SERT，而不会影响TPH1的表达。

还需要在临床试验中进行进一步的研究，以了解5-HT和CD之间的确切联系。尽管如此，通过降低5-HT水平，LGG可能是帮助改善CD临床症状的潜在策略。