Microbiota Modulates the Immunomodulatory Effects of Filifolinone on Atlantic Salmon.

Filifolinone is an aromatic geranyl derivative, a natural compound isolated from Heliotropum sclerocarpum, which has immunomodulatory effects on Atlantic salmon, upregulating cytokines involved in Th1-type responses through a mechanism that remains unknown. In this work, we determined whether the immunomodulatory effects of filifolinone depend on the host microbiotic composition. We evaluated the effect of filifolinone on immune genes and intestinal microbiotic composition of normal fish and fish previously treated with bacitracin/neomycin. Filifolinone induced the early expression of IFN-α1 and TGF-ß, followed by the induction of TNF-α, IL-1ß, and IFN-γ. A pre-treatment with antibiotics modified this effect, mainly changing the expression of IL-1ß and IFN-γ. The evaluation of microbial diversity shows that filifolinone modifies the composition of intestinal microbiota, increasing the abundance of immunostimulating organisms like yeast and firmicutes. We identified 69 operational taxonomic units (OTUs) associated with filifolinone-induced IFN-γ. Our results indicate that filifolinone stimulates the immune system in two ways, one dependent on fish microbiota and the other not. To our knowledge, this is the first report of microbiota-dependent immunostimulation in Salmonids.

Evaluation in vitro of proliferative activity of epithelial cells by flavonoid 3-O-methylgalangine and terpenenic derivative Filifolinone / Evaluación in vitro de la actividad proliferative de células epiteliales del flavonoide 3-O-metilgalangina y el derivado terpénico Filifolinona

The skin is the largest organ of the human body and its main function is to protect it from the external environment. It is exposed to injuries that require a rapid healing process to recover its functionality. Microorganisms inhabit the skin, which makes up the normal microbial flora, but in situations of injury they can cause infections that slow down the regeneration process. Therefore, there is a great interest in the development of alternative methods to accelerate the regeneration process and prevent infections. In this work, the efficacy of flavonoid 3-O-methylgalangine and the terpenic derivative Filifolinone and its mixtures, isolated from plants of the genus Heliotropium, on the stimulation of cell proliferation was evaluated. The results showed that the mixtures stimulated proliferation and migration in MA104 cells mainly due to the presence of Filifolinone, that together with the known antibacterial activity of 3-O-methylgalangine, opens new alternatives for the use of natural compounds in healing processes.

La piel es el órgano más grande del cuerpo humano y su función principal es protegerla del entorno externo. Está expuesta a lesiones que requieren un proceso de curación rápido para recuperar su funcionalidad. Los microorganismos que habitan en la piel, constituyen la flora microbiana normal, pero en situaciones de lesión pueden causar infecciones que retardan el proceso de regeneración. Por lo tanto, existe un gran interés en el desarrollo de métodos alternativos para acelerar el proceso de regeneración y prevenir infecciones. En este trabajo, se evaluó la eficacia del flavonoide 3-O-metilgalangina y el derivado terpénico Filifolinona y sus mezclas, aisladas de plantas del género Heliotropium, en la estimulación de la proliferación celular. Los resultados mostraron que las mezclas estimularon la proliferación y la migración en las células MA104 debido principalmente a la presencia de Filifolinona, que junto con la actividad antibacteriana conocida de la 3-O-metilgalangina, abre nuevas alternativas para el uso de compuestos naturales en los procesos de curación.

Key cytokines of adaptive immunity are differentially induced in rainbow trout kidney by a group of structurally related geranyl aromatic derivatives.

Filifolinone is a semi-synthetic terpenoid derivative obtained from Heliotropium filifolium that increases the expression level of pro-inflammatory and anti-inflammatory cytokines in kidney cells of salmon. Because cytokines are produced in response to a foreign organism and by distinct other signals modulating immune responses, we further studied the potential immunomodulatory effects of a group of structural related terpenoid derivatives from H. filifolium on salmonids to determine the relationship between the chemical structure of the derivatives and their ability to modify cytokine expression and the lymphoid content. The resin and four 3H-spiro 1-benzofuran-2,1'-cyclohexane derivatives were tested in vivo in rainbow trout (Oncorhynchus mykiss) by quantifying the transcript levels of antiviral and T helper-type cytokines and T and B cells in the kidney. Three of the four terpenoids differ only in the C-7'substituent of the cyclohexane and the presence of the ketone group at this position in Filifolinone appeared responsible of an important up-regulation of IFN-α1, IFN-γ, IL-4/13A and IL-17D in the kidney of the treated trout. In addition, the absence of a methoxy group in carbon 7 of the benzene ring, found in all compounds but not in Folifolinoic acid, produced a significant reduction of IFN-γ, IL-12 and IL-4/13A transcripts. B cells were not affected by the compound treatment but Filifolinoic acid and the resin induced a significant reduction of T cells. Altogether, results showed that immunomodulating responses observed in the trout by effect of 3H-spiro 1-benzofuran-2,1'-cyclohexane derivatives is related to the presence of the ketone group in the carbon 7' and the methoxy group in carbon 7 of the benzene ring, being Filifolinone the most active immunostimulatory compound identified.

Immunomodulatory effects of the aromatic geranyl derivative filifolinone tested by the induction of cytokine expression.

Fish farming crops are constantly exposed to infectious diseases due to intensive production conditions under which microorganisms develop and spread easily, resulting in severe economic losses. The massive use of antibiotics to control these diseases has lead to the accumulation of residues and the development of drug resistance. Consequently, it is urgent to develop new pharmacological tools to stimulate protective immune responses in salmonids to combat infectious diseases. We evaluated the immunostimulant activity of terpenoid derivatives isolated from species of the Heliotropium genus, which had previously shown antiviral activity in salmon. The immunomodulatory effects of the 3 H-spiro [1-benzofuran-2,1'-ciclohexane] derivative called filifolinone, were studied in vitro using the SHK-1 cell line derived from leucocytes of salmon head kidney and in vivo in Atlantic salmon. For the evaluation, we studied the effect of this compound in the expression of various cytokines. The results showed that Filifolinone increases the levels of expression of pro-inflammatory and anti-inflammatory cytokines. This suggests that Filifolinone is a potential alternative immunomodulator for veterinary purposes.

In vitro immunostimulant activity of the aromatic geranyl derivative Filifolinone / Actividad inmunoestimulante in vitro del derivado aromático geranilado Filifolinona

The in vitro effect of the 3 H-spiro [1-benzofuran-2,1’-ciclohexane] derivative (Filifolinone), was evaluated on mouse dendritic cells through the level of expression of MHC molecules class II by flow cytometry. The results show that Filifolinone increases the expression of MHC promoting maturation of dendritic cells. The results suggest that Filifolinone is a potential immunomodulator for veterinary use.

La actividad in vitro del derivado 3H-espiro [1-benzofurano-2,1’-ciclohexano] (Filifolinona), fue evaluado en células dendríticas de ratón a través del nivel de expresión de moléculas MHC clase II utilizando citometría de flujo. Los resultados muestran que Filifolinona incrementa la expresión de MHC promoviendo la maduración de las células dendríticas. Estos resultados permiten sugerir que Filifolinona es un potencial inmunomodulador de uso veterinario.