Theoretical Basis for Herbal Medicines, Tokishakuyaku-San and Sairei-To, in the Treatment of Recurrent Abortion: Enhancing the Production of Granulocyte?Macrophage Colony-Stimulating Factor in Decidual Stromal Cells

Efficacy and safety of the traditional herbal medication Chai-Ling-Tang (in China), Siryung-tang (in Republic of Korea) or Sairei-To (in Japan)

ETHNOPHARMACOLOGICAL RELEVANCE

The herbal medicine designated Chai-Ling-Tang in China, Siryung-tang in South Korea, and Sairei-To (or Tsumura Saireito extract granules, TJ-114) in Japan is a complex polyherbal formulations with 12 plant components. It is used historically to treat Shaoyang syndrome, recorded in an ancient Chinese medical text "Treatise on Cold Damage Disorder" (Shanghan Lun). Chai-Ling-Tang formula combines two traditional Chinese herbal medicine prescriptions: Xiao-Chai-Hu-Tang and Wu-Ling-San (known as Sho-Saiko-To and Goreisan in Japan, and So Shi Ho Tang and Oreonsang in Korea, respectively). These traditional Chinese/Korean medicines and Kampo medicine have been used for more than 2000 years in East Asia, notably as regulators of body fluid homeostasis.

AIM OF THE STUDY

This study aims to evaluate clinical uses, pharmacological effects and unwanted effects of Sairei-To through a narrative literature survey. The main active phytoconstituents and their mechanism of actions are also collated based on the literature.

METHODS

Several databases including SciFinder and PubMed were searched in sourcing information using keywords corresponding to the medicinal treatment names and the corresponding plants and phytochemicals. Relevant textbooks, reviews, and digital documents (mostly in English) were consulted to collate all available scientific literature and to provide a complete science-based survey of the topic.

RESULTS

Sairei-To derives from ten plants and two fungi. The three major components are Bupleuri radix (Saiko), Pinelliae rhizoma (Hange), and Alismatis rhizoma (Takusha). The rest includes the species Scutellariae radix, Zizyphi fructus, Ginseng radix, Glycyrrhizae radix, Zingiberis rhizoma, Cinnamomi cortex, Atractylodis lanceae rhizoma, Poria sclerotium, and Polyporus sclerotium. The therapeutic uses of Sairei-To are very diversified, ranging from the treatment of autoimmune diseases, intestinal inflammatory disorders, edema, intestinal and kidney diseases, cancers, inflammatory skin pathologies, and other conditions such as reproductive failure. Sairei-To is considered as a safe and efficient medication, with potential rare unwanted side effects, notably lung injuries (pneumonitis essentially). Marked anti-inflammatory and immune-modulatory effects of Sairei-To have been reported, generally associated to the action of saponins (saikosaponins, glycyrrhizin), terpenoids (alisols) and flavonoids (baicalin, oroxylin A).

CONCLUSION

Sairei-To is commonly used to treat inflammatory diseases and appears efficient to decrease the side effects of corticosteroids. Its immune-regulatory action is well recognized and exploited to treat certain skin lesions and chemotherapy-related toxic effects. The activity of the Sairei-To product relies on the synergistic action of its individual ingredients. Further studies are warranted to quantify the synergy of action inherent to this interesting botanical medication.

Saireito (114) Increases IC50 and Changes T-Cell Phenotype When Used in Combination with Prednisolone Therapy in Human Peripheral Blood Mononuclear Cells

Prednisolone (PSL), a type of corticosteroid used to treat autoimmune diseases, can increase the risk of infection and osteoporosis. Saireito (114), a Kampo medicine, has an immunosuppressive effect; with its use, the dose of steroids can be reduced. However, its mechanism when used with PSL is still unclear. We used peripheral blood mononuclear cells (PBMCs) from healthy adults to examine the effect of 114 and PSL treatment on PBMC proliferation, T-cell subsets, and cytokine production. PBMCs were cotreated with concanavalin A and 300 μM 114 (either Tsumura & Co. (TJ) or Kracie Holdings (KR)) and 0.0001–1.0 μM PSL for 96 h to create the T-cell mitogen. We then measured the PBMC proliferation; ratio of CD4⁺ T cells, CD8⁺ T cells, and T-follicular helper (Tfh) cells; and concentration of cytokines (TNF, IFN-γ, IL-6, IL-10, IL-17A, and IL-21). The proliferation of PBMCs was dose dependently suppressed in both the PSL and PSL + 114 groups (p  <  0.05). Combination therapy increased the IC₅₀ in the PSL group (0.0947 μM) by 2.02 and 1.64-fold in the PSL + TJ114 and PSL + KR114 groups, respectively. Both the PSL + 114 groups had an increased ratio of CD4⁺ T cells compared to the PSL group, with no effect on the ratio of CD8⁺ T and Tfh cells. Furthermore, the PSL + 114 groups showed increased IL-6 and IL-10 compared to the PSL monotherapy group, although the difference was not significant. There was no significant difference in the TNF, IFN-γ, IL-17A, and IL-21 concentrations between the PSL and PSL + 114 groups. The elevated IC₅₀ with 114 cotreatment suggests diminished immunosuppressive action. Moreover, increased cytokine production by Th2 with 114 cotreatment suggests a restoration of T-cell balance in Th1-mediated autoimmune diseases. However, increased IL-6 suggests potential exacerbation of IL-6-mediated diseases, such as rheumatoid arthritis. Therefore, it is necessary to monitor these clinical parameters when using 114 in combination with PSL.

Immunological Differences in Human Peripheral Blood Mononuclear Cells Treated with Traditional Japanese Herbal Medicines Hochuekkito, Juzentaihoto, and Ninjin'yoeito from Different Pharmaceutical Companies

Hochuekkito (HET), Juzentaihoto (JTT), and Ninjin'yoeito (NYT) have been used as Hozai, a group of traditional Japanese herbal medicines, to treat physically and mentally weak cancer patients. Their compositions are quite different, and Japanese pharmaceutical companies have been using different types or quantities of herbs for formulations with the same name. Here, we compared the immunological differences between HET, JTT, and NYT with respect to the induced T cell subsets and cytokines. Peripheral blood mononuclear cells (PBMCs) were isolated from healthy volunteers and treated with 0 (control), 25, 50, 100, 200, or 400 μg/mL HET, JTT, or NYT (manufactured by Tsumura [TJ], Kracie [KR], and Kotaro [KO]). PBMC proliferation, CD4⁺ T cell, CD8⁺ T cell, and regulatory T cell (Treg) proportions and interleukin (IL) concentrations (IL-6, IL-10, IL-17A, interferon-γ, tumor necrosis factor-α, and transforming growth factor (TGF)-β) secreted by PBMCs were measured using Cell Counting Kit-8 or flow cytometry bead analysis. PBMC proliferation and CD4⁺ T cell percentages were similar in the HET, JTT, NYT, and control groups; however, the percentage of CD8⁺ T cells tended to increase after treatments. Tregs were suppressed by HET, JTT, and NYT, and TJ-JTT significantly decreased Treg numbers (compared with control). The concentrations of all cytokines except TGF-β were increased in a concentration-dependent manner (p < 0.05); particularly, KR-HET induced IL-6 secretion (compared with the control, TJ-HET, and KO-HET; 37-, 7-, and 17-fold, respectively; p < 0.05). The TGF-β concentration was decreased in a concentration-dependent manner by HET, JTT, and NYT (compared with the control). These results suggest that, compared with TJ-HET and KO-HET, KR-HET should be administered with caution. Although HET, JTT, and NYT belong to the same Hozai group and have the same names among companies, their differing effects on immune activity must be considered and they must be administered with caution.

Tokishakuyakusan, a traditional Japanese medicine (Kampo) mitigates iNKT cell-mediated pregnancy loss in mice

OBJECTIVE

Tokishakuyakusan (TSS) is a traditional herbal medicine that has been used empirically to prevent recurrent pregnancy loss. Its mode of action remains unclear. With their potent capacity to produce cytokines, invariant natural killer (iNKT) cells are involved in the control of fetomaternal immunity in early gestation. This study aimed to clarify the effect of TSS on iNKT cell activities in a well-studied murine miscarriage model.

METHODS

Pregnant mice were fed 1% TSS-containing or control diet from the day of vaginal plug formation. Alpha-galactosylceramide (AGC) was administered intraperitoneally to the pregnant mice at day 9.5 postcoitus (pc) to stimulate iNKT cells. Peripheral cytokine levels were evaluated using cytokine arrays. The percentage of iNKT cells among splenocytes was examined by flow cytometric analysis. The incidence of pregnancy loss was assessed at day 12.5 pc.

RESULTS

The ratio of fetal resorptions to total conceptuses was significantly higher in the group exposed to TSS (34%) than in controls (78%). A rapid and robust surge in inflammatory cytokines, including IFN-γ and TNF-α, was detected in the peripheral blood of control animals 2 hours after AGC administration. This peripheral cytokine induction was significantly attenuated in the TSS-fed group compared with the control. The percentage of iNKT cells among total splenocytes was lower in the TSS-fed group than in controls.

CONCLUSION

The findings in this study suggest that the inhibitory effects of TSS on pregnancy loss may involve immune modulation of iNKT cells during early pregnancy.