Effect of a novel food rich in miraculin on the oral microbiome of malnourished oncologic patients with dysgeusia

Abstract

Dysgeusia contributes to the derangement of nutritional status in patients with cancer, as well as worsening the quality of life. The pharmaceutical industry has failed to provide effective treatments for patients suffering from taste disorders. The present study provided a novel strategy to reduce side effects in patients with cancer through the administration of a novel food supplement approved by the European Union, Dried Miracle Berries (DMB), containing the taste-modifying glycoprotein miraculin, as an adjuvant to medical-nutritional treatment. This was done in a pilot randomized, parallel, triple-blind, and placebo-controlled intervention clinical trial in which 31 malnourished patients with cancer and dysgeusia receiving antineoplastic treatment were randomized into three arms [standard dose of DMB (150 mg DMB/tablet), high dose of DMB (300 mg DMB/tablet) or placebo (300 mg freeze-dried strawberry)] for three months. Patients consumed a DMB or placebo tablet before each main meal. Using the Nanopore methodology, we analyzed the oral microbiome of patients with cancer using saliva samples. All patients with cancer and dysgeusia had dysbiosis in terms of lower bacterial diversity and richness. DMB consumption was associated with changes in oral microbiome composition. Neither selected bacteria, nor taste perception, type of diet, and cytokine levels were associated with mucositis. Likewise, alcohol and tobacco consumption as well as general and digestive toxicity due to systemic therapy was not associated to specific changes of the oral microbiota. The standard dose of DMB resulted in a greater relative abundance ofEnterococcusand a lower abundance ofVeillonellacompared with the high DMB dose and placebo. In particular, some species such asGranulicatella elegans,Granulicatella adiacens,Streptococcus mutans, andGemella morbillorumshowed higher relative abundances in the DMB standard-dose group; in contrast,Streptococcus parasanguinis,Veillonella parvula,Streptococcus australis, andStreptococcus cristatuswere less abundant. Additionally, the consumption of a standard dose of DMB revealed a negative association between the concentrations of TNF-α and the abundance of species such asStreptococcus thermophilus,Streptococcus pneumoniae,Streptococcus dysgalactiaeandStreptococcus agalactiae.Accordingly, regular DMB consumption changed the oral microbiome in patients with cancer and dysgeusia, which may contribute to maintaining an appropriate immune response without changing taste perception. However, as the present pilot study involved a small number of participants, further studies are necessary draw robust conclusions from the data.HighlightsPatients with cancer and dysgeusia exhibit a dysbiotic state in terms of bacterial diversity and richness.The regular consumption of a standard dose of Dried Miracle Berries (DMB), rich in miraculin, before each main meal for three months as an adjuvant to medical-nutritional treatment, improves the oral microbiome composition in malnourished patients with cancer and dysgeusia.Several species i.e.,Granulicatella elegans,Granulicatella adiacens,Streptococcus mutans, andGemella morbillorum, show higher relative abundances in the DMB standard-dose group; in contrast,Streptococcus parasanguinis,Veillonella parvula,Streptococcus australis, andStreptococcus cristatusare less abundantDMB consumption is negatively associated with some species ofStreptococcusand TNF-α concentrations in malnourished patients with cancer and dysgeusia.Neither of the highly represented bacteria are associated with the presence or absence of mucositis, digestive toxicity, or tobacco use and alcohol consumption or a change in taste perception at the end of the intervention.