In this study were observed different levels of immune cells in lymph nodes and spleen tissue in normal/healthy BALBc mice group. In lymph nodes (LNs) there are almost 80% TL/NK cells and in Spleen there are about 40% TL/NK cells and similar % in granulocytes.
Dexamethasone can alter the normal responses of the immune system and, therefore, be useful in the treatment of certain diseases that affect the immune system, such as anemia (aplastic and hemolytic), thrombocytopenia and purple. Corticosteroids are used to treat rheumatoid arthritis, inflammatory bowel disease, and many other conditions. These drugs also help suppress the immune system to prevent organ rejection in transplant recipients. GCs (glucocorticoids) are fat-soluble molecules, are easily absorbed on any skin or mucosal surface, circulate in the blood, bound to proteins and the free fraction is the one that diffuses inside the cells, exerting its action. Although the simple diffusion mechanism through the lipid bilayer of cell membrane is the most accepted, there is evidence that its entry into the cell is regulated through membrane receptors other than the steroid receptor (GR). They would use G proteins as signals and this mechanism would be responsible for the rapid actions of these hormones . However, the exact molecular mechanism of GCs such as dexamethasone are not yet fully elucidated.
In this study were observed that dexamethasone treatment did not deplete the level of immune cells in Spleen but affected more than 92% the TL/NK and BL cells level in Lymph nodes. As was reported in 2018, Dexamethasone-mediated T cell suppression diminishes naïve T cell proliferation and differentiation , these findings are in accordance with our results.
Were also observed that the treatment with dexamethasone did not deplete the level of dranulocytes (neutrophils, basophils and eosinophils) nor either in LNs or spleen tissue. These results are partially agreed with a discovery performed in 1999, explained by the fact that glucocorticoids are known to negatively modulate apoptosis of human neutrophils ; however, it is still unclear by which mechanism delay the granulocytes death.
Beta-glucans are naturally occurring polysaccharides, glucose polymers are constituents of the cell wall of certain pathogenic bacteria and fungi. These mushrooms contain biologically active polysaccharides that mostly belong to beta-glucans groups, that increase host immune defense by activating complement system, enhancing macrophages and natural killer cell functions . Maitake (Grifola frondosa) has been prized in traditional Japanese herbology for hundreds of years. Modern science has identified in Maitake Proteoglycan, beta-1,3 and 1,6 glucans, as an active constituent to support the immune system. Maitake D-fraction is a standardized form of pure and active proteoglycan, contains 6000 mg of extract from Maitake mushroom (PD-Fraction TM) in alcohol free vegetable glycerin base.
In our studies were observed that the Maitake Pro4X treatment acts antagonistically with the immunosuppressor dexamethasone, recovering more than 40% the level of depleted TL/NK cells but are unable to recover the depleted level of BL/stem cells, however, surprisingly increased more than 700 times the granulocytes level in lymph nodes. Meaning that, under immune-depletion condition, Maitake Pro4X activate the production of granulocytes cells in lymph nodes ready to blood circulation to protect the host, also were observed in this study that Maitake Pro4X significantly help recovering in about 40% the completed depleted level of TL/NK cells in lymph nodes due to dexamethasone treatment. A study performed in 2010, indicates that oral MBG (Maitake mushroom Grifola frondosa) promoted maturation of HPC (human hematopoietic progenitor cells) to become functionally active myeloid cells and enhanced peripheral blood leukocyte recovery after chemotoxic bone marrow injury .
The conclusion in the present study opens a light to see good potential for beta-glucans from Maitake Pro4X in the immune system of mice, and it still interesting to considered Maitake Pro4X as immunosuppressor antagonist agent in patients with certain clinical conditions, contrasting the negative effect of such treatments, and recovering the level of the white cells for the host immune defense. Regarding the immune system, the regulation of its activation or suppression could contribute to the maintenance of a good state of host health. The use of agents that activate host defense mechanisms (immunostimulatory, immunopotentiators or biological response modifiers) could provide an additional therapeutic tool to conventional chemotherapy.
Based on these results, now will be interesting to understand by which molecular mechanism the beta-glucans from Maitake Pro4X are able to recover the Dexamethasone-depleted immune cells.