Immune adjuvant effect of Juzentaihoto, a Japanese traditional herbal medicine, on tumor vaccine therapy in a mouse model

CD8+ T Cell-Mediated Therapeutic Antitumor Effect of an Herbal Mixture Containing Ganoderma lucidum

Although Kampo-a traditional Japanese herbal medicine-contributes in the control of tumor growth in vivo in experimental animals, most of the antitumor effects are prophylactic and not therapeutic. In this study, we determined whether oral administration of an herbal mixture containing Ganoderma lucidum (WTMCGEP; Wisteria floribunda, Trapae fructus, Myristica fragrans, Coicis semen, Ganoderma lucidum, Elfvingia applanata, and Punica granatum), anecdotally used in Japan for the palliative care of patients with cancer, exhibits a therapeutic effect on tumor growth in vivo in a hypodermic murine CT26 colorectal tumor model. An in vitro tumor assay revealed that WTMCGEP extract has some direct influence over suppression of tumor growth. In wild-type BALB/c mice, WTMCGEP did not show any antitumor effect in vivo. However, in BALB-CD1d^-/- mice with partly mitigated immunosuppression by reason of them being devoid of both antitumoral type I and immunosuppressive type II natural killer T (NKT) cells, WTMCGEP therapeutically suppressed tumor growth. CD8⁺ T cell depletion significantly accelerated tumor growth in WTMCGEP mice; therefore, its antitumor activity was primarily in a CD8⁺ T cell-dependent manner. Regarding immunosuppressive cells in tumor-bearing CD1d^-/- mice, WTMCGEP did not influence the abundance of tumor-infiltrating CD4⁺ and Forkhead box protein 3⁺ regulatory T cells. However, it reduced both intratumoral and splenic Ly6G⁺ Ly6C^lo polymorphonuclear myeloid-derived suppressor cells, which were most likely involved in tumor growth inhibition related to higher frequency of intratumoral CD107a⁺ CD8⁺ T cells in these mice. Overall, these data illustrate that the deficiency of NKT cells urges WTMCGEP to exert a therapeutic antitumor effect mainly through CD8⁺ T cells. Our efforts are the first to scientifically demonstrate the WTMCGEP's contribution to tumor immunity.

Japanese Kampo Medicine Juzentaihoto Improves Antiviral Cellular Immunity in Tumour-Bearing Hosts

Global and antigen-independent immunosuppression by growing tumours can cause life-threating damage when concurrent with an infection in tumour-bearing hosts. In the present study, we investigated whether the oral administration of the Japanese traditional herbal (Kampo) medicine, juzentaihoto (JTT), plays a role in the improvement of antiviral cellular immunity in tumour-bearing hosts. Female BALB/c mice subcutaneously injected with murine colorectal cancer CT26 cells fed a control or JTT diet were inoculated with recombinant vaccinia virus expressing human immunodeficiency virus-1 glycoprotein 160 (vSC25). At 7 days postinfection, anti-vSC25 cellular immunity was evaluated by measuring the abundance of splenic virus-specific CD8⁺ T cells. JTT had no impact on CT26 tumour growth in vivo. Surprisingly, JTT augmented anti-vSC25 cellular immunity in CT26-bearing mice. Depletion of either CD25⁺ regulatory T (Treg) cells or myeloid-derived suppressor cells (MDSCs) also enhanced anti-vSC25 cellular immunity in tumour-bearing mice but had no therapeutic benefit against tumour growth. However, JTT had no impact on the abundance of these immunosuppressive cells. Overall, our data indicates that JTT contributes to the improvement of anti-vSC25 cellular immunity in tumour-bearing hosts possibly via a mechanism independent of CD25⁺ Treg cells and MDSCs, suggesting that this Kampo medicine can act as a promising antiviral adjuvant in an immunosuppressive state caused by tumours.

Immunostimulatory properties of heat-resistant RNA in a decoction of Glycyrrhizae Radix

Research on the bioactive components of herbal medicines have been conducted mainly on the secondary metabolites of herbal plants. Accordingly, limited information is available on primary metabolites (carbohydrates, amino acids, lipids, and nucleic acids) and their biological effects. Here, we focused on the heat-resistant RNA of a decoction of Glycyrrhizae Radix and showed its immunostimulatory effects. The RNA activated NF-κB/AP-1 and induced TNF-α production in murine macrophages. Further analysis revealed that the RNA was around 90 nucleotides long. RNA sequencing (RNA-Seq) by next generation sequencing (NGS) showed that approximately 30% of the NGS reads were mapped to the genome of Glycyrrhiza uralensis, which is plant material of Glycyrrhizae Radix. Further analysis of the other 70% of reads indicated that the RNA contained RNA sequences that could be mapped to various microorganisms. Together, these results propose nucleic acids as a new research field in the bioactive components of herbal medicines.

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.

Intron retention as a new pre-symptomatic marker of aging and its recovery to the normal state by a traditional Japanese multi-herbal medicine

Intron retention (IR) is an important regulatory mechanism that affects gene expression and protein functions. Using klotho mice at the pre-symptomatic state, we discovered that retained-introns accumulated in several organs including the liver and that among these retained introns in the liver a subset was recovered to the normal state by a Japanese traditional herbal medicine. This is the first report of IR recovery by a medicine. IR-recovered genes fell into two categories: those involved in liver-specific metabolism and in splicing. Metabolome analysis of the liver showed that the klotho mice were under starvation stress. In addition, our differentially expressed gene analysis showed that liver metabolism was actually recovered by the herbal medicine at the transcriptional level. By analogy with the widespread accumulation of intron-retained pre-mRNAs induced by heat shock stress, we propose a model in which retained-introns in klotho mice were induced by an aging stress and in which this medicine-related IR recovery is indicative of the actual recovery of liver-specific metabolic function to the healthy state. Accumulation of retained-introns was also observed at the pre-symptomatic state of aging in wild-type mice and may be an excellent marker for this state in general.

Combination of Juzentaihoto and chemotherapy improves the prognosis of patients with postoperative recurrence of non-small cell lung cancer

Kampo medicines have been used to reduce chemotherapy-induced adverse events. However, whether Kampo medicine can improve the prognosis of cancer remains unclear. The present study aimed to clarify the effect of Juzentaihoto (TJ-48) on patients with postoperative recurrence of non-small cell lung cancer. In total, 45 patients with postoperative recurrent non-small cell lung cancer scheduled for first-line chemotherapy were enrolled in the present study. Differences in progression-free survival between the chemotherapy combined with TJ-48 and chemotherapy only groups were analyzed. Body weight change and prognostic nutritional index were also evaluated to examine whether these factors were influenced by TJ-48 administration. Multivariate analysis was performed to detect independent prognostic factors. A significant increase was observed in progression-free survival in the chemotherapy plus TJ-48 group compared with in the chemotherapy alone group (P<0.001). Significant decreases in body weight and prognostic nutritional index score were observed in the chemotherapy alone group (P<0.01 and P<0.05, respectively); however, these decreases were not observed in the chemotherapy plus TJ-48 group. Multivariate analysis revealed that TJ-48 administration with chemotherapy was an independent prognostic factor. In conclusion, TJ-48 combined with chemotherapy may improve the progression-free survival of patients with postoperative recurrence of non-small cell lung cancer by preventing nutritional disorders.

Japanese Kampo Medicine Juzentaihoto Enhances Antitumor Immunity in CD1d-/- Mice Lacking NKT Cells

Although the Japanese traditional herbal medicine (Kampo), Juzentaihoto (JTT), has been reported to have antitumor effects in several tumor models, its role in tumor immunology remains controversial. In the present study, we tested whether oral administration of JTT enhances antitumor immunity in CD1d^−/− mice, in which immunosuppression was partially relieved due to the lack of NKT cells. In a subcutaneous murine syngeneic CT26 colorectal tumor model, JTT had no impact on tumor growth in wild type (WT) BALB/c mice. However, the growth rate of tumors was significantly slower in CD1d^−/− mice than in WT mice. Surprisingly, JTT significantly delayed tumor growth in such CD1d^−/− mice. In vivo depletion of CD8⁺ T cells revealed that CD8⁺ T cells are required for JTT’s antitumor activity. Moreover, tumor-reactive cytotoxic T-lymphocytes were detected exclusively in JTT-treated mice with well-controlled tumors. JTT did not affect the number of tumor-infiltrating CD4⁺ regulatory T cells. On the contrary, JTT increased the degranulation marker CD107a⁺ CD8⁺ T cells and decreased Ly6G⁺ Ly6C^lo polymorphonuclear myeloid-derived suppressor cells in tumor-infiltrating lymphocytes, most probably contributing to the suppression of tumor growth in JTT-treated mice. Nonetheless, JTT had no impact on the proportion of monocytic myeloid-derived suppressor cells. In conclusion, our results indicate that in the absence of NKT cells, JTT augments antitumor immunity by CD8⁺ T cells, suggesting that this Kampo medicine is a promising anticancer adjuvant when negative immune regulation is partially relieved.

Novel trisaccharide based phospholipids as immunomodulators

A focused library of novel mannosylated glycophospholipids was synthesized employing imidate coupling and H-phosphate phosphorylation methods. All novel glycophospholipids were evaluated for their receptor interactions by molecular docking studies. Docking studies revealed dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) specific interaction of the glycophospholipid ligand P4 acts, which was further confirmed by in vitro DC-SIGN expression on monocyte-derived dendritic cells (MoDCs). Further, in vitro and in vivo immunomodulatory activity among the six compounds (P1-P6) examined, compound P4 displayed good immunopotentiation and adjuvant properties as indicated by the induced cytokine expression and enhanced ovalbumin (OVA) specific antibody (IgG) titers. Phosphatidylinositol mannosides (PIMs) analogues in the present study enforced the immunomodulatory properties, truncating parent PIMs or tailor-made of PIMs may bring the novel efficacious molecules, which will be useful in vaccine preparation against different diseases.

Juzentaihoto hot water extract alleviates muscle atrophy and improves motor function in streptozotocin-induced diabetic oxidative stress mice

A decrease in skeletal muscle mass and motor function occurs in diabetic patients. In type 1 diabetic patients, in particular, fast-type fiber-dominated muscle atrophy occurs due to increased oxidative stress and inflammation. Juzentaihoto is a herbal medicine that has been found to be effective in reducing oxidative stress. In this study, juzentaihoto hot water extract (JTT) was administered prophylactically to mice with diabetic oxidative stress, which was induced by an injection of streptozotocin, and the effects on skeletal muscle mass, motor function, and antioxidant activity were evaluated. In mice that were administered JTT, skeletal muscle atrophy and loss of motor function were suppressed. Additionally, the administration of JTT increased the mRNA expression level of Sirt1 and the activity of superoxide dismutase in the gastrocnemius. In addition to skeletal muscle atrophy, atrophy of the liver, spleen and thymus gland, and kidney hypertrophy were also suppressed. Furthermore, in order to evaluate the antioxidant activity of 10 constituent crude drugs that comprise juzentaihoto, Sirt1 transcriptional activity in C2C12 cells was evaluated. The Sirt1 transcriptional activity was increased by Cinnamomi Cortex, Astragali Radix, and Glycyrrhizae Radix extracts. These three constituent crude drugs play an important function in the antioxidant action of juzentaihoto, suggesting that juzentaihoto can prevent muscle atrophy by decreasing oxidative stress.

Sipjeondaebo-tang Alleviates Oxidative Stress-Mediated Liver Injury through Activation of the CaMKK2-AMPK Signaling Pathway

Sipjeondaebo-tang (SDT) is used frequently as a herbal prescription to treat deficiency syndromes in traditional Korean medicine. We investigated the hepatoprotective effects of SDT against oxidative stress and attempted to clarify the underlying molecular mechanisms. SDT pretreatment reduced arachidonic acid (AA) plus iron-mediated cytotoxicity in a concentration-dependent manner and prevented changes in apoptosis-related protein expression. In addition, SDT pretreatment significantly reduced glutathione depletion, hydrogen peroxide production, and mitochondrial dysfunction via treatment with AA plus iron. SDT increased the phosphorylation of AMP-activated protein kinase (AMPK) in accordance with the phosphorylation of Ca²⁺/calmodulin-dependent protein kinase kinase 2 (CaMKK2). Experiments using an AMPK chemical inhibitor (Compound C) or CaMKK2 chemical inhibitor (STO-609) suggested that the CaMKK2-AMPK signaling pathway contributes to SDT-mediated protection of mitochondria and cells. Moreover, administration of SDT for 4 consecutive days to mice significantly reduced the alanine aminotransferase and aspartate aminotransferase activities induced by carbon tetrachloride, and the numbers of degenerated hepatocytes, infiltrated inflammatory cells, nitrotyrosine-positive cells, and 4-hydroxynonenal-positive cells in liver tissue. Therefore, SDT protects hepatocytes from oxidative stress via CaMKK2-dependent AMPK activation and has the therapeutic potential to prevent or treat oxidative stress-related liver injury.

Discovery of a sugar-based nanoparticle universally existing in boiling herbal water extracts and their immunostimulant effect

Herbal medicine is mainly prepared from boiling herbal water extracts. Many epoch-making immunosuppressant drugs, such as glycyrrhizic acid (old example) and FTY720 (current example), were developed from herbal secondary metabolites in the boiling water extract by partition with organic solvents. However, few immunostimulants have been discovered by this method. Instead of the usual method, we aimed to find a novel immunostimulant component by two unique methods in the research of herbal medicine: ultracentrifugation and electron microscopy. The immunostimulant was not a secondary metabolite, as expected, but the structure was a nanoparticle formed by a polysaccharide. In addition, we clarified the immune effect of the nanoparticle. Intake of the nanoparticle by phagocytosis resulted in immunostimulant effects by increasing the genes and proteins of inflammatory cytokines in macrophage cells. The immunostimulant effects were inhibited by a phagocytosis inhibitor, cytochalasin D. To the best of our knowledge, this study is the first to describe the discovery of a nanoparticle in boiling herbal water extracts and its immunostimulant properties. This study will provide additional understanding of the efficacy of herbal medicine, in that the immunostimulant nanoparticle universally exists in boiling herbal water extracts. Thus, traditional herbal medicine may be an oldest known nanomedicine. Furthermore, this study suggests that the immunostimulant nanoparticle simply can be obtained from herbal medicine only by ultracentrifugation. We hope that this simple strategy will substantially contribute to drug development, including vaccine adjuvant, in the future.

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Nanoparticles are universally present in boiling herbal water extracts.

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Nanoparticles are obtained from these extracts by ultracentrifugation.

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Nanoparticles are mainly composed of polysaccharides.

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Nanoparticles have an immunostimulatory effect on macrophage cells.

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This effect is exhibited by the phagocytosis of exogenous nanoparticles.

Japanese Kampo medicine ninjin'yoeito synergistically enhances tumor vaccine effects mediated by CD8+ T cells

Although Japanese traditional herbal medicine (Kampo) has been widely applied to the treatment of various diseases, including cancer, their mechanisms of action have not yet been elucidated in detail, particularly regarding their role in tumor immunology. The present study investigated the antitumor effects of the Japanese Kampo medicine, ninjin'yoeito (NYT; Ren-Shen-Yang-Rong-Tang in Chinese), which was orally administered with or without an irradiated tumor cell vaccine to a subcutaneous CT26 colon carcinoma tumor model. The irradiated tumor cell vaccine in a prophylactic setting significantly delayed tumor growth in mice fed a control diet, whereas a diet containing NYT alone did not exert any antitumor effects in vivo. However, the inhibition of tumor growth was significantly greater in vaccinated mice fed the NYT diet compared with in vaccinated mice given the control diet. These results suggest that NYT synergistically enhances the effects of the antitumor vaccine. The depletion of cluster of differentiation (CD)8⁺ T cells abrogated these effects, indicating that antitumor activity required CD8⁺ T cells. Furthermore, reductions in CD4⁺ CD25⁺ and forkhead box protein 3⁺ T regulatory cell numbers were more apparent between vaccinated mice fed the NYT diet and non-vaccinated mice fed the control diet than between vaccinated mice and non-vaccinated mice fed the control diet, suggesting that the weaker impact of T regulatory cells contributes to the augmentation of antitumor immunity by CD8⁺ T cells in vaccinated mice fed with NYT. Overall, these results indicate that NYT synergistically enhances the effects of the prophylactic tumor vaccine mediated by CD8⁺ T cells and that this Japanese Kampo medicine has potential as a useful adjuvant agent for cancer immunotherapy.