Combined treatment of autoimmune MRL/MP-lpr/lpr mice with a herbal medicine, Ren-shen-yang-rong-tang (Japanese name: Ninjin-youei-to) plus suboptimal dosage of prednisolone

Administration of chinpi, a component of the herbal medicine ninjin-youei-to, reverses age-induced demyelination

The disruption of myelin causes severe neurological diseases. An understanding of the mechanism of myelination and remyelination is essential for the development of therapeutic strategies for demyelination diseases. Our previous findings indicated that the FcRγ/Fyn cascade is a potential therapeutic target for remyelination caused by the Chinese/Japanese traditional herbal (Kampo) medicine ninjin'youeito (Ninjin-youei-to, NYT), which is a hot-water extract made from 12 medicinal herbs. To identify which constituents of NYT are involved in the reversal of demyelination and to examine the potential therapeutic effect, we tested several of the chemical constituents of NYT. Here, we report that Chinpi, a constituent of NYT, upregulates the FcRγ/Fyn signaling cascade resulting in a potentially therapeutic effect against age-induced demyelination. In addition, we observed that phosphorylated (activated) FcRγ/Fyn upregulated the expression of the 21.5 kDa isoform of myelin basic protein, inducing rapid morphological differentiation, when oligodendrocyte precursor cells (OPCs) were cultured in the presence of hesperidin and/or narirutin (the major active constituents of Chinpi). These results suggest that hesperidin and narirutin participate in the FcRγ/Fyn signaling pathway in OPCs causing these cells to differentiate into myelinating oligodendrocytes.

Mineralocorticoid receptor mediates glucocorticoid treatment effects in the autoimmune mouse ear

The standard treatment for many hearing disorders is glucocorticoid therapy, although the cochlear mechanisms involved in steroid-responsive hearing loss are poorly understood. Cochlear dysfunction in autoimmune mice has recently been shown to be controlled with the mineralocorticoid aldosterone as effectively as with the glucocorticoid prednisolone. Because aldosterone regulates sodium, potassium, and other electrolyte homeostasis, this implied the restoration of hearing with the mineralocorticoid was due to its impact on cochlear ion transport, particularly in the stria vascularis. This also suggested glucocorticoids may be controlling hearing recovery in part through their binding to the mineralocorticoid receptor in addition to their glucocorticoid receptor-mediated anti-inflammatory and immunosuppressive functions. Therefore, the aim of the present study was to better delineate the role of the mineralocorticoid receptor in steroid control of hearing in the autoimmune mouse. Spironolactone, a mineralocorticoid receptor antagonist, was administered to MRL/MpJ-Fas(lpr) autoimmune mice in combination with either aldosterone or prednisolone to compare their hearing and systemic disease with mice that received either steroid alone. ABR thresholds showed either aldosterone or prednisolone alone preserved hearing in the mice, but spironolactone prevented both steroids from maintaining normal cochlear function. This suggested both steroids are preserving hearing through the mineralocorticoid receptor within the ear to regulate endolymph homeostasis. The spironolactone treatment did not block normal glucocorticoid receptor-mediated immune-suppression functions because mice receiving prednisolone, either with or without spironolactone, maintained normal body weights, hematocrits, and serum immune complexes. Thus, reducing systemic autoimmune disease was not sufficient to control hearing if mineralocorticoid receptor-mediated functions were blocked. It was concluded the inner ear mineralocorticoid receptor is a significant target of glucocorticoids and a factor that should be considered in therapeutic treatments for steroid-responsive hearing loss.

A newly devised formulation for self-medication enhances interferon-gamma production and proliferation of splenic lymphocytes

A newly devised formulation for self-medication in Toyama, PanaWang, is a new herbal medicine (so called Toyama original brand formulation) developed based on traditional philosophy and scientific evidence. We here tried to examine the effect of oral administration of PanaWang on the balance of type I helper T cells (Th1) and Th2 cells. Splenic lymphocytes from normal mice were stimulated with Concanavalin A (Con A) in vitro and the secretion of Th1- and Th2-type cytokines, interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) respectively, was investigated. Con A-induced production of IFN-gamma from spleen cells, but not IL-4, was enhanced by the administration of PanaWang. Increased production of IFN-gamma was also detected in splenic lymphocytes from Th2-predominant BALB/c mice after DNP-immunization, without a change in antigen-specific IgE levels in vivo. Antigen-specific proliferative responses were also increased in lymphocytes from PanaWang-treated mice. These findings raise the possibility that PanaWang has Th1-stimulating activity and induces Th1-predominant immunity.

Effects of Hochu‐ekki‐to and Ninjin‐youei‐to, Traditional Japanese Medicines, on Porcine Serum‐Induced Liver Fibrosis in Rats

In this study, we estimated the effects of traditional Japanese medicines on liver fibrosis in Wistar rats injected with porcine serum twice a week for 8 weeks. The rats were orally administered Hochu-ekki-to, Ninjin-youei-to (100 and 300 mg/kg/day) or Sho-saiko-to (300 mg/kg/day) 5 days per week. Serum and liver samples were obtained 2 days after the last porcine serum injection. Hochu-ekki-to and Ninjin-youei-to showed significant suppressive effects on the increase in hepatic hydroxyproline, namely total collagen. Further, Ninjin-youei-to significantly suppressed the increases of type IV collagen localized in the basement membrane and prolyl 4-hydroxylase, a collagen synthesis enzyme, in serum or liver. Hochu-ekki-to showed a similar trend. Although Sho-saiko-to did not significantly suppress the increase in hepatic hydroxyproline, it intensely suppressed serum type IV collagen. Further, Hochu-ekki-to, Ninjin-youei-to, and Sho-saiko-to inhibited the production of fibrogenic cytokines, namely TGF-beta1 and IL-13, in the serum and liver. Additionally, we showed that IL-13 levels were positively correlated with hydroxyproline contents in the liver. These results suggest that Ninjin-youei-to as well as Hochu-ekki-to suppress porcine serum-induced liver fibrosis more effectively than Sho-saiko-to. The effects of these three medicines probably depend on the inhibition of fibrogenic cytokine production, resulting in the suppression of collagen synthesis and deposition in the liver, though different mechanisms underlie their anti-fibrogenic effects.

Effect of a traditional Chinese herbal medicine, Ren-Shen-Yang-Rong-Tang (Japanese name: Ninjin-Youei-To), on oligodendrocyte precursor cells from aged-rat brain

Understanding of oligodendrocyte precursor cells and their role in the generation of oligodendrocytes in developing and adult rodents has been considered, particularly much less is known about aged-rodent oligodendrocyte precursor cells and their cell lineage. In this present study, we have developed oligodendrocyte cultures from the 30-month-old rat brain and examined whether oligodendrocyte precursor cells can proliferate in vitro. Adult oligodendrocyte precursor cells (O1(-), O4(+)) and oligodendrocytes (O1(+), O4(+)) are present in the cultures of the 30-month-old rat brain. They are also capable of proliferating and differentiating in the cultures. These capabilities increased four- to fivefold, when the aged rats are treated with Ninjin-Youei-To for 3 months in comparison with those of control aged rats. These results suggest that Ninjin-Youei-To has a potential mitotic effect on oligodendrocyte precursor cells in aged-rat brains and may be expected to have a therapeutic effect on brain aging.

Effect of ninjin-youei-to on Th1/Th2 type cytokine production in different mouse strains

Ninjin-youei-to (NYT; ren-shen-yang-rong-tang in Chinese) is a traditional herbal formula, which is widely used in Japan, Korea and China to modulate physiological immunity. The effects of oral administration of NYT on cytokine production from splenocytes were investigated in both C57BL/6 and BALB/c mice in which Th1 and Th2 were dominant, respectively. Splenocytes from C57BL/6 and BALB/c mice, which took NYT orally forfour weeks, were cultured with anti-mouse CD3 mAb, and the supernatant was examined for cytokine production using enzyme-linked immunosorbent assay (ELISA). Administration of NYT to C57BL/6 mice, increased the production of interleukin-4 (IL-4) significantly, and slightly decreased interferon-y (IFN-gamma) production from splenocytes. In contrast, the same treatment significantly increased IFN-gamma secretion from splenocytes of BALB/c mice. No remarkable changes of IL-12 production from splenocytes were observed in either strain of mice. These results suggest that oral administration of NYT ameliorates the excessive inclination of Th1 and Th2 type cytokine production, and NYT may provide a beneficial effects for the treatment of diseases caused by a skewed Th1-Th2 balance in the immune system.

Aldosterone and prednisolone control of cochlear function in MRL/MpJ-Fas(lpr) autoimmune mice

Recently this laboratory showed aldosterone, a mineralocorticoid that only enhances sodium transport, was as effective as the glucocorticoid prednisolone in restoring cochlear function in autoimmune mice. To further test this relationship between sodium transport and autoimmune hearing loss, dosage comparisons were made of prednisolone and aldosterone control of the auditory dysfunction in autoimmune MRL/MpJ-Fas(lpr) mice. Mice were tested at 2 months of age to establish baseline auditory brainstem response (ABR) thresholds, hematocrit, serum immune complexes, and anti-nuclear antibodies. Mice were then given different doses of prednisolone or aldosterone in their drinking water for 2 months. After the treatment period, most untreated water controls showed elevation of ABR thresholds due to the ongoing autoimmune disease. However, the steroid groups had significantly more mice with improved or unchanged thresholds. Both steroids improved stria vascularis morphology, although aldosterone appeared to be more effective. The immune suppressive prednisolone caused a dose-related improvement in levels of serum immune complexes and hematocrit, hallmarks of systemic autoimmune disease. Aldosterone, which has no immune suppressive function, did not alter systemic disease. The comparable efficacy of prednisolone and aldosterone in restoring auditory function suggests steroid reversal of autoimmune hearing loss in mice is due to increasing stria vascularis sodium transport and not suppression of systemic autoimmune reactions.

Steroid treatment in young MRL.MpJ-Fas(lpr) autoimmune mice prevents cochlear dysfunction

Corticosteroid therapy reverses clinical autoimmune sensorineural hearing loss, although little is known of how steroids restore normal auditory function. If suppression of systemic autoimmune processes underlies hearing restoration, then preventing autoimmune symptoms from developing should prevent cochlear dysfunction. MRL. MpJ-Fas(lpr) autoimmune mice were used to test this potential mechanism by initiating oral prednisolone treatment at 6 weeks of age, prior to autoimmune disease and hearing loss onset. The steroid treatment group was given prednisolone in their drinking water, while untreated controls were given tap water. Treatment continued for 7 months with periodic evaluations of cochlear function with auditory brainstem response (ABR) audiometry. Autoimmune mice given the steroid lived longer and did not develop levels of serum immune complexes seen in their untreated controls. Also, their ABR thresholds remained near normal throughout the 7 months of treatment, while untreated controls showed progressive threshold elevations typical for autoimmune disease. This correlation of suppressed systemic autoimmune activity and maintenance of normal cochlear function identifies one potential mechanism for autoimmune hearing loss and hearing restoration with steroid therapy. The autoimmune mouse should serve as a valuable model for future studies of the cochlear mechanisms responsive to steroid treatment in autoimmune hearing loss.

Steroid treatment improves cochlear function in the MRL.MpJ-Fas(lpr) autoimmune mouse

Corticosteroid therapy is used to reverse autoimmune sensorineural hearing loss, although little is known of the mechanism by which this occurs. This has been due to the lack of a suitable animal model with spontaneous hearing loss that is steroid responsive. The present study examined the effects of prednisolone treatment on auditory thresholds in the MRL.MpJ-Fas(lpr) autoimmune mouse to determine its suitability as such a model. Autoimmune mice at 3.5-4. 5 months of age were evaluated by pure-tone auditory brainstem response (ABR) to establish threshold elevations due to the disease. The steroid treatment group was then given prednisolone in their drinking water for 2.5 months, while untreated controls were given tap water. Significantly more steroid treated mice survived to the time of post-treatment ABR evaluation. Half of the steroid treated ears demonstrated either improvement or no change in cochlear function compared to only 25% in the untreated controls. Overall, cochlear thresholds in the untreated controls increased by 14.7 dB, whereas no significant threshold increase was seen in the steroid treated group (4.3 dB) over the treatment period. No qualitative anatomical differences were seen in the ears of those mice surviving to the end of the study. These findings establish the autoimmune mouse as a model for studies of steroid responsive mechanisms within the ear. This could apply to autoimmune sensorineural hearing loss, as well as any hearing disorder for which steroid therapy is recommended.

Combined treatments with Ninjin-youei-to (Ren-shen-yang-rong-tang) plus a suboptimal dose of prednisolone on autoimmune nephritis in MRL/lpr mice

MRL/lpr mice suffer from a systemic lupus erythematosus-like autoimmune disease. We studied the effects of oral treatments with Ninjin-youei-to (NYT, Ren-shen-yang-rong-tang, 1000 mg/kg/day), a suboptimal dose (2 mg/kg/day) of prednisolone(PSL) and their combination on nephritis in MRL/lpr mice. Treatments with NYT or PSL alone inhibited the development of proteinuria and prolonged survival. The combined treatment reduced the incidence of proteinuria and prolonged survival. In histological analysis, NYT treatments decreased the degree of mesangial proliferative glomerulonephritis and infiltration of mononuclear cells in the kidneys. PSL treatment was effective in reducing periglomerular nephritis and vasculitis in addition to such effects as NYT and NYT plus PSL treatment was more effective than PSL alone. The active form of TGF-beta was reduced in NYT and PSL-treated mouse serum, and the combined treatments further suppressed it. However, the treatment with NYT alone did not induce a decrease in the latent form of TGF-beta. The effect of NYT can be assumed to be different from an immunosuppressive effect of PSL. Therefore, the combined treatment with NYT and PSL can be expected to be more useful for the therapy of autoimmune disease such as nephritis, compared with NYT or PSL alone treatments.

Thymus-dependent effects of a traditional Chinese medicine, ren-shen-yang-rong-tang (Japanese name; Ninjin-youei-to), in autoimmune MRI/MP-lpr/lpr mice

Autoimmune MRL/lpr mice were i.p. treated with 200 mg/kg Ren-shen-yang-rong-tang (Japanese name: Ninjin-youei-to, NYT), a traditional Chinese herbal medicine (Japanese name: Kampo), from 8 weeks of age every 3 days before the onset of autoimmune disease Compared to age-matched control MRL/lpr mice, the serum IL-6 concentration in NYT-treated mice was decreased, their serum IFN-gamma concentration was increased, and the proliferative responses of whole and enriched CD4+ cells in their spleen and lymph nodes stimulated with ConA in vitro were restored. FACS analysis revealed that the rate of decreased CD4+CD8+ T-cell population in the thymus was decreased in MRL/lpr mice but recovered by NYT treatment. Further, adult thymectomized (ATX) MRL/lpr mice were treated with 200 mg/kg NYT similarly. NYT treatment prolonged the survival of sham-operated MRL/lpr mice and ameliorated their proteinuria but did not improve such autoimmune manifestations in ATX-MRL/lpr mice. These findings suggest that NYT plays an important role in the abrogation of autoimmune-prone T cell differentiation and that the therapeutic effect of NYT is dependent on the thymus in MRL/lpr mice.

Combined treatment with ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to) plus prednisolone on adjuvant-induced arthritis in Lewis rat

The effects of combined treatment with 250 mg/kg Ren-shen-yang-rong-tang (Japanese name: Ninjinyouei-to, NYT) plus 4 mg/kg, an average dosage, or 0.2 mg/kg, a suboptimal dosage, of prednisolone (PSL) on adjuvant-induced arthritis in Lewis rats were investigated using two treatment schedules. The agents were administered orally every day from day 0 to 21 (schedule A), or from day -7 to 21 (schedule B) after adjuvant injection. PSL treatment (4 mg/kg) obviously inhibited paw swelling due to non-immune inflammation, diminished the weights of the thymus, spleen, adrenals and iliac lymph nodes, and suppressed the increment of serum interleukin (IL)-6 concentration in both schedules compared to controls. NYT treatment alone inhibited paw swelling due to immune inflammation, diminished the weight of the adrenals and decreased IL-6 concentration only in schedule A. Combined treatment with NYT plus PSL (4 mg/kg) showed: (1) a superior effect to that of PSL on paw swelling in the uninjected hind foot, especially in schedule B, (2) a tendency to diminish adrenal weight in schedule A and the weights of all four organs in schedule B compared with PSL treatment alone, and (3) a suppressive effect on IL-6 concentration weaker than that of PSL alone in schedule B. The suppressive effect of combined treatment with NYT plus PSL (0.2 mg/kg) on paw swelling was significantly stronger compared with either NYT or PSL treatment alone in schedule B. Although this dose of PSL had no influence upon the IL-6 concentration, the combined treatment or NYT alone increased the IL-6 concentration.(ABSTRACT TRUNCATED AT 250 WORDS)