Shih-Hua Fang

Ribavirin enhancement of hepatitis C virus core antigen-specific type 1 T helper cell response correlates with the increased IL-12 level

BACKGROUNDS/AIMS Combination IFN-a and ribavirin therapy for hepatitis C virus-infected patients has been reported to improve the response rate up to 50%. In this study, we aimed to study further the role of ribavirin in hepatitis C virus-specific immune responses. METHODS We immunized mice with hepatitis C virus core protein with or without different concentrations of ribavirin. Forty days after immunization, hepatitis C virus-specific immune responses were followed in these mice. RESULTS We found that the mice immunized with core antigen once every 2 weeks and 0.5 mg ribavirin every day showed higher levels of core-specific IgG2 compared with those mice immunized with core antigen only. In addition, core antigen-stimulated spleen cells produced higher levels of T helper type 1 cytokines and the core-specific cytotoxic T cell activity also increased significantly. Furthermore, lipopolysaccharide-stimulated peritoneal cells produced higher levels of IL-12 in ribavirin-treated mice, and peritoneal cells isolated from naive mice also produced significantly higher level of IL-12 when cultured with ribavirin. CONCLUSIONS Ribavirin may significantly promote the T helper type 1 immune response in vivo, and, furthermore, the effect of ribavirin on IL-12 level produced by accessory cells may contribute to the T helper type 1 enhancing effect.

Changes of mucosal immunity and antioxidation activity in elite male Taiwanese taekwondo athletes associated with intensive training and rapid weight loss

Objective The aim of this study was to investigate the cumulative effects of prolonged, intensive training and rapid weight loss on immunological parameters and antioxidation activity of elite male Taiwanese taekwondo athletes. Design 16 Elite male taekwondo athletes (mean age, 21.6 (1.3) years; mean height, 173.7 (5.5) cm) volunteered to participate in this study. Beginning at 30 days before a national competition, saliva samples were obtained during a 7-week training, the competition and the postcompetition period. Levels of salivary IgA, cortisol, lactoferrin and free-radical scavenging activity were measured at 30-, 14-, 7- and 1-day precompetition and 1-, 7- and 19-day postcompetition. Body weight and body fat were also recorded. Results The mean body weight was notably decreased during the week immediately before the competition. Results reveal that the levels of salivary IgA were differentially regulated during the training, competition and recovery period, while the salivary cortisol and lactoferrin concentrations and free-radical scavenging activity were not appreciably affected during the training and the competition period. Furthermore, the results of an upper respiratory tract infection incidence indicate that following the decreases of mucosal immunity, the risk of acquiring infection was significantly increased. Conclusions Our results demonstrated that mucosal immunity in elite male taekwondo athletes is modulated by exercise and rapid weight reduction during the training, competition and recovery period. Cumulative effects of prolonged intensive training and rapid weight reduction suppressed mucosal immunity. Furthermore, because of the “open window” of impaired immunity during the precompetition period, the incidence of upper respiratory tract infection was significantly increased after the competition.

Constituents isolated from Cordyceps militaris suppress enhanced inflammatory mediator's production and human cancer cell proliferation.

AIM OF THE STUDY The purpose of this study is to isolate the pure compounds from the extracts of Cordyceps militaris obtained through solid-state cultivation process, and evaluate their anti-inflammatory and anticancer properties. MATERIALS AND METHODS Silica gel column chromatographic purification of Cordyceps militaris extracts resulted in the isolation of 10 pure compounds (1-10). The compounds 1-10 were examined for their growth inhibitory properties against nitric oxide (NO), tumor necrosis factor (TNF)-alpha and interleukin (IL)-12 enhanced production from LPS/IFN-gamma-stimulated macrophages. Additionally, the anti-proliferation effects of 1-10 on human cancer cell lines, colon (colon 205), prostate (PC-3), and hepatoma (HepG2) cells were also analyzed. RESULTS Compound 8 displayed potent growth inhibition on NO, TNF-alpha and IL-12 production with an IC(50) value of 7.5, 6.3, and 7.6 microg/ml, respectively. A similar inhibitory trend on these inflammatory mediators was observed for 3, 7, 9 and 10 with an IC(50) values ranging from 10.8 to 17.2 microg/ml. On the other hand, compounds 3 and 8 were potent anti-proliferative agents with an IC(50) value of 35.6 and 32.6 microg/ml toward PC-3 and colon 205 cell lines, respectively. The compounds 1 and 2 showed potent anti-proliferation in PC-3 and colon 205 cells, while only 3 displayed such effect in HepG2 cells. CONCLUSION The present study provides scientific supporting information for the ethnopharmacological use of Cordyceps militaris as an anti-inflammatory and anticancer agent.

Honokiol inhibits LPS-induced maturation and inflammatory response of human monocyte-derived dendritic cells†

Honokiol (HNK) is a phenolic compound isolated from the bark of houpu (Magnolia officinalis), a plant widely used in traditional Chinese and Japanese medicine. While substantial evidence indicates that HNK possesses anti‐inflammatory activity, its effect on dendritic cells (DCs) during the inflammatory reaction remains unclear. The present study investigates how HNK affects lipopolysaccharide (LPS)‐stimulated human monocyte‐derived DCs. Our experimental results show that HNK inhibits the inflammatory response of LPS‐induced DCs by (1) suppressing the expression of CD11c, CD40, CD80, CD83, CD86, and MHC‐II on LPS‐activated DCs, (2) reducing the production of TNF‐α, IL‐1β, IL‐6, and IL‐12p70 but increasing the production of IL‐10 and TGF‐β1 by LPS‐activated DCs, (3) inhibiting the LPS‐induced DC‐elicited allogeneic T‐cell proliferation, and (4) shifting the LPS‐induced DC‐driven Th1 response toward a Th2 response. Further, our results show that HNK inhibits the phosphorylation levels of ERK1/2, p38, JNK1/2, IKKα, and IκBα in LPS‐activated DCs. Collectively, the findings show that the anti‐inflammatory actions of HNK on LPS‐induced DCs are associated with the NF‐κB and mitogen‐activated protein kinase (MAPK) signaling pathways. J. Cell. Physiol. 226: 2338–2349, 2011.

Ribavirin Enhances Interferon-γ Levels in Patients with Chronic Hepatitis C Treated with Interferon-α

Some patients with chronic hepatitis C respond to interferon (IFN)-α treatment, and the efficiency can be improved by combining it with ribavirin. The mechanism of this improvement is unknown. To investigate the effects of these two regimens on the immune responses in 51 patients with chronic hepatitis C, we examined the hepatitis C core antigen-specific proliferative response and cytokine production profiles, natural killer (NK) cell cytotoxicity and cytotoxic T cell function during treatment. The results are as follows: (1) both viral clearance and biochemical normalization occurred more frequently in patients receiving combination therapy; (2) the function of NK cells increased after treatment in the responders of both groups (p<0.05); (3) the level of IFN-γ produced by hepatitis C core antigen-stimulated peripheral blood mononuclear cells was higher in patients receiving combination therapy, especially in responders; (4) the core antigen-specific proliferative response decreased after treatment, and (5) in addition, the core-specific cytotoxic T cell activities of five responder patients also increased significantly after therapy. In conclusion, enhancement of immune responses, especially those related to type-1 T helper cell activity, may contribute to better efficacy in combining ribavirin with IFN-α for treatment of chronic hepatitis C.

Immunomodulatory Effects of Lactobacillus and Bifidobacterium on Both Murine and Human Mitogen-Activated T Cells

Background: Beneficial effects of probiotics have been reported for patients with allergic diseases and intestinal disorders. There is increasing interest in studying the role of different strains or combined probiotic administration on immunoregulation. In this study, we investigated whether probiotics modulate the immune response through regulating T cell proliferation and differentiation. Methods: We examined the effect of probiotic I (a combination of Lactobacillus acidophilus and Bifidobacterium bifidus) and probiotic II (a combination of L. acidophilus and B. infantis) on cell survival and proliferation, the progression of the cell cycle, and the production of Th1/Th2 cytokines by mitogen-stimulated murine spleen cells and human peripheral blood mononuclear cells (PBMCs). Results: Our experimental results showed that high concentrations (≧1 × 106 CFU/ml) of probiotic I or II inhibited mitogen-induced cell proliferation and arrested the cell cycle at the G0/G1 stage in both mitogen-stimulated spleen cells and PBMCs. In the results of low concentrations (<1 × 106 CFU/ml), probiotic I or II enhanced the production of IFN-γ but inhibited the production of IL-4. Our results indicated that high concentrations of probiotic I or II treatment could attenuate mitogen-induced overactive immune responses. On the other hand, low concentrations of probiotic I or II treatment could promote a shift in the Th1/Th2 balance toward Th1-skewed immunity. Conclusion: Dose selection is an important issue for probiotic studies. Our results indicated that probiotics have beneficial effects on regulating T cell-mediated immune responses by attenuating mitogen-induced overactive immune responses and promoting Th1 immune responses.

Potential ex vivo immunomodulatory effects of San-Huang-Xie-Xin-Tang and its component herbs on mice and humans

AIM OF THE STUDY San-Huang-Xie-Xin-Tang (SHXXT), an important Chinese medicine formula, contains Rhei Rhizoma (RR), Scutellariae Radix (SR) and Coptidis Rhizoma (CR). RR and SR are abundant in anthraquinone and flavonoid polyphenols. Pharmacokinetic study of SHXXT indicated that glucuronides were the predominant forms of polyphenols in rats. MATERIALS AND METHODS As an extension of pharmacokinetic study, the serum metabolites of SHXXT, RR, SR and CR were prepared from rats and quantitated, then the immunomodulation effects were examined by culturing these serum metabolites with murine and human immune cells. RESULTS The results indicated that the inhibitions on nitric oxide (NO) and cytokine production from mitogen-activated peritoneal macrophages by the serum metabolites of SHXXT, RR, SR and CR were through reducing the protein expression of inducible NO synthase (iNOS) and the IC(50) were 0.8%, 1.5%, 3.0% and 0.8% of their blood concentrations, respectively. In addition, the serum metabolites of SHXXT, RR, SR and CR significantly decreased the ratios of interferon-gamma (IFN-gamma) to interleukin (IL)-4 in mitogen-stimulated mice spleen cells and human peripheral blood mononuclear cells (PBMCs). Moreover, the serum metabolites of SHXXT and SR significantly arrested the mitogen-stimulated mice spleen cells at G2/M stage. CONCLUSIONS In conclusion, the serum metabolites of SHXXT and the component herbs exerted promising modulation activities on the immune functions and the cell cycle distribution of mice and human immune cells. We suggest that SHXXT is a promising remedy for immunomodulation through Th1/Th2 regulation.

Functional Measurement of Hepatitis C Virus Core-Specific CD8+ T-Cell Responses in the Livers or Peripheral Blood of Patients by Using Autologous Peripheral Blood Mononuclear Cells as Targets or Stimulators

ABSTRACT As is widely recognized, CD8+ cytotoxic T lymphocytes (CTLs) play a crucial role in hepatitis C virus (HCV) infection, both in pathogenesis of liver injury and in clearing the virus. CTL studies with HCV-infected patients have been difficult because of the relatively low frequency of CTL precursors in the peripheral blood and because the targeted epitopes vary depending on the human leukocyte antigen (HLA) types of the individuals. This study attempts to overcome these problems by assessing the feasibility of using autologous peripheral blood mononuclear cells (PBMCs) expressing viral antigens as stimulators or targets in order to monitor the CTL responses. Primary PBMCs were transduced using a retroviral vector pseudotyped with a vesicular stomatitis virus G glycoprotein expressing the HCV core gene. Additionally, the vector-transduced PBMCs were used as targets of CTL assays to measure the HCV core-specific CTL activities from the liver-infiltrating lymphocytes of six different HLA-type patients with chronic HCV infection. The core-expressing PBMCs also served as stimulators, allowing us to measure core-specific CD8+T-cell responses by intracellular gamma interferon staining of the peripheral blood of hepatitis C patients who had received treatment with alpha interferon plus ribavirin. This approach provides an efficient means of measuring antigen-specific CTL responses without HLA constraints.

Effects of carbohydrate, branched-chain amino acids, and arginine in recovery period on the subsequent performance in wrestlers

Many athletes need to participate in multiple events in a single day. The efficient post-exercise glycogen recovery may be critical for the performance in subsequent exercise. This study examined whether post-exercise carbohydrate supplementation could restore the performance in the subsequent simulated wrestling match. The effect of branched-chain amino acids and arginine on glucose disposal and performance was also investigated. Nine well-trained male wrestlers participated in 3 trials in a random order. Each trial contained 3 matches with a 1-hr rest between match 1 and 2, and a 2-hr rest between match 2 and 3. Each match contained 3 exercise periods interspersed with 1-min rests. The subjects alternated 10-s all-out sprints and 20-s rests in each exercise period. At the end of match 2, 3 different supplementations were consumed: 1.2 g/kg glucose (CHO trial), 1 g/kg glucose + 0.1 g/kg Arg + 0.1 g/kg BCAA (CHO+AA trial), or water (placebo trial). The peak and average power in the 3 matches was similar in the 3 trials. After the supplementation, CHO and CHO+AA trial showed significantly higher glucose and insulin, and lower glycerol and non-esterified fatty acid concentrations than the placebo trial. There was no significant difference in these biochemical parameters between the CHO and CHO+AA trials. Supplementation of carbohydrate with or without BCAA and arginine during the post-match period had no effect on the performance in the following simulated match in wrestlers. In addition, BCAA and arginine did not provide additional insulinemic effect.

Morin Promotes the Production of Th2 Cytokine by Modulating Bone Marrow-Derived Dendritic Cells

Our previous studies had reported that morin decreased the interleukin-12 (IL-12) and tumor necrosis factor-alpha (TNF-alpha) production in lipopolysaccharide (LPS)-activated macrophages, suggesting that morin may promote helper T type 2 (Th2) response in vivo. Dendritic cells (DCs) are the most potent antigen presenting cells and known to play a major role in the differentiation of helper T type 1 (Th1) and Th2 responses. This study aimed to reveal whether morin is able to control the Th differentiation through modulating the maturation and functions of DCs. Bone marrow-derived dendritic cells (BM-DCs) were incubated with various concentrations of morin and their characteristics were studied. The results indicated that morin significantly affects the phenotype and cytokine expression of BM-DCs. Morin reduced the production of IL-12 and TNF-alpha in BM-DCs, in response to LPS stimulation. In addition, the proliferative response of stimulated alloreactive T cells was significantly decreased by morin in BM-DCs. Furthermore, allogeneic T cells secreted higher IL-4 and lower IFN-gamma in response to morin in BM-DCs. In conclusion, these results suggested that morin favors Th2 cell differentiation through modulating the maturation and function of BM-DCs.