Immunomodulatory and antioxidant effects of carboxymethylpachymaran on the mice infected with PCV2

The objective of the current study is to investigate the protective effect of carboxymethylpachymaran (CMP) on the immune system of mice via multiple infections with porcine circovirus type 2 (PCV2). The in vivo results showed that CMP administration significantly improved the spleen or thymus index, promoted the proliferation activities of T or B lymphocytes, and increased the production of glutathione, the superoxidase dismutase capacity, and the total antioxidant capacity in the spleen or thymus of PCV2-infected mice. The administration of different CMP doses to PVC2-inoculated mice resulted in the upregulation of IL-2 and IFN-α or the downregulation of IL-10 levels in the serum. These findings suggest that CMP has potential applications in regulating immunological functions to overcome the immunosuppresion caused by PCV2 infection in mice. The findings may also prove useful in designing effective therapies against PCV2 infection.     

The interaction of neutrophilic granulocytes with Candida albicans fungi in the formation of mycotic foci under conditions of immunodepression

In the electron-microscopic study of the interaction of neutrophil granulocytes with the fungal species C. albicans in the process of the formation of mycotic foci in mice under the conditions of cyclophosphamide-induced immunosuppression, mouse leukocytes have been found to retain their capacity for migration to the focus of inflammation and for the phagocytosis of fungal cells. At the same time the fungicidal activity of leukocytes is decreased, which is manifested by the prevalence of viable fungal cells with the partially digested cell wall in the cytoplasm of leukocytes.     

Modulating effects of the synergistic combination of extracts of herbal drugs on cyclophosphamide-induced immunosuppressed mice

ObjectiveTaking leads from the available research, we aimed to develop a synergy-based herbal combination of Tinospora cordifolia (TC), Phyllanthus emblica (PE), and Piper nigrum (PN). Also, evaluating their synergistic effect on CP-induced immunosuppression in mice model and exploring the possible mechanisms involved in reversing the damage.MethodologyThe immunomodulatory activity of combination, of TC stem, PE fruits, and PN dried fruits, was determined by in vitro assays (splenocyte proliferation and pinocytic activity of peritoneal macrophages of mice) and in vivo study using CP-induced immunosuppression model in Swiss Albino mice. The ratio was optimized for combining three by in vitro MTT assay. The combination was further evaluated for anti-oxidant activity by DPPH scavenging method and quantified for its bioactive metabolites by HPTLC. Serum collected on day 0, 4, 7 and 14 was employed for estimation of haematogram (haematocrit, TLC, DLC, and haemoglobin, etc) and immune parameters (IL-10, IL-6 and TNF-α) by ELISA.ResultsThe study demonstrated, that combination of herbal extracts at an intermediate dose could inhibit the proliferation of spleen cells and peritoneal macrophages (P ≤ 0.0001) and induce suppression of pro-inflammatory mediators, and also certified that combination exerts synergized effects. The results showed that the combination possess potential antioxidant activity by DPPH scavenging method (IC₅₀-113.5 µg/ml). It was identified that combination significantly (P ≤ 0.0001) improved the immune markers, haematogram parameters, and histological parameters, with maximum protection offered by an intermediate dose.ConclusionThe results suggested that present combination could be further explored clinically as potent synergy-based therapeutic approach for immune modulation.     

Role for the Epidermal Growth Factor Receptor in Chemotherapy-Induced Alopecia

Treatment of cancer patients with chemotherapeutics like cyclophosphamide often causes alopecia as a result of premature and aberrant catagen. Because the epidermal growth factor receptor (EGFR) signals anagen hair follicles to enter catagen, we hypothesized that EGFR signaling may be involved in cyclophosphamide-induced alopecia. To test this hypothesis, skin-targeted Egfr mutant mice were generated by crossing floxed Egfr and Keratin 14 promoter-driven Cre recombinase mice. Cyclophosphamide treatment of control mice resulted in alopecia while Egfr mutant skin was resistant to cyclophosphamide-induced alopecia. Egfr mutant skin entered catagen normally, as indicated by dermal papilla condensation and decreased follicular proliferation, but did not progress to telogen as did Egfr wild type follicles. Egfr mutant follicles responded with less proliferation, apoptosis, and fewer p53-positive cells after cyclophosphamide. Treatment of control mice with the EGFR inhibitors erlotinib or gefitinib similarly suppressed alopecia and catagen progression by cyclophosphamide. Secondary analysis of clinical trials utilizing EGFR-targeted therapies and alopecia-inducing chemotherapy also revealed evidence for involvement of EGFR in chemotherapy-induced alopecia. Taken together, our results demonstrated the involvement of EGFR signaling in chemotherapy-induced alopecia, which will help in the design of novel therapeutic regimens to minimize chemotherapy-induced alopecia.     

兽疫链球菌荚膜多糖对免疫抑制鼠的抗氧化和免疫调节活性研究

目的测定部分纯化的兽疫链球菌荚膜多糖（PCP）的抗氧化和免疫调节活性。方法以注射用环磷酰胺（CY）造成免疫抑制鼠模型。结果口服PCP诱导了免疫抑制鼠超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶（CAT）的活性,提高了总抗氧化能力（TAOC）的水平。口服PCP后免疫抑制鼠的胸腺和脾脏指数明显增加,血清溶菌酶活性和迟发型超敏反应（DTH）引起的肿胀率也显著提高。结论 PCP对免疫抑制鼠具有免疫调节功能并改变CY诱导的氧化压力,是一种潜在的抗氧化剂和免疫调节剂。     

Antioxidant activities of polysaccharides from Hyriopsis cumingii

The antioxidant activities of crude Hyriopsis cumingii polysaccharides (HCPS) were evaluated both in vitro and in vivo. In vitro antioxidant assay, HCPS (crude and its purified fraction) could scavenge hydrogen peroxide, free radicals of superoxide anion and 2,2-diphenyl-1-picryl-hydrazyl, chelate ferrous ion and reduce ferric ion. Except for metal ion chelating activity, HCPS-3 exhibited much higher antioxidant activities than crude HCPS, HCPS-1 and HCPS-2. For antioxidant testing in vivo, different doses of crude HCPS were orally administrated over a period of 15 days in a d-galactose induced aged mice model. As results, administration of crude HCPS inhibited significantly the formation of malondialdehyde in mice livers and serums and raised the activities of antioxidant enzymes and total antioxidant capacity in a dose-dependent manner. The results suggested that HCPS had direct and potent antioxidant activities.     

Effect of taxifolin on cyclophosphamide-induced oxidative and inflammatory bladder injury in rats

The role of oxidative stress and inflammation in the pathogenesis of cyclophosphamide-related side effects has been demonstrated in previous studies. This study aimed to investigate the effect of taxifolin, due to its antioxidant and anti-inflammatory properties, on cyclophosphamide-induced oxidative and inflammatory bladder injury in albino Wistar rats. The taxifolin+cyclophosphamide (TCYC) group was given 50 mg/kg of taxifolin orally by gavage. Normal saline was used as a solvent for the cyclophosphamide (CYC) group and the healthy control (HC) group. One hour after taxifolin administration, 75 mg/kg of cyclophosphamide was intraperitoneally injected in the TCYC and CYC groups. This procedure was repeated once a day for 30 days. At the end of this period, biochemical markers were studied in the excised bladder tissues and histopathological evaluations were conducted. In the histopathological evaluation of the CYC group, severe epithelial irregularity, dilatation, congestion, and polymorphonuclear leukocyte accumulation in the vascular structures were observed. Additionally, the malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) levels, the total oxidant status (TOS), and the oxidative stress index (OSI) values were significantly higher, and the total glutathione (tGSH) levels and total antioxidant status (TAS) were significantly lower in the CYC group in comparison to the HC group (P<0.001). Taxifolin reduced the cyclophosphamide-induced increases in the MDA, TNF-α, IL-1β, and IL-6 levels and the TOS and OSI values; it decreased the tGSH and TAS levels and reduced histopathological damage (P<0.001). Taxifolin may be useful in the treatment of cyclophosphamide-induced bladder damage.     

Combining a peptide vaccine with oral ingestion of Lentinula edodes mycelia extract enhances anti-tumor activity in B16 melanoma-bearing mice

New anticancer vaccines must overcome regulatory T cell (Treg)-mediated immunosuppression. We previously reported that oral ingestion of Lentinula edodes mycelia (L.E.M.) extract restores melanoma-reactive T cells in melanoma-bearing mice via a mitigation of Treg-mediated immunosuppression. In this study, we investigated the effect of oral ingestion of the extract on peptide vaccine-induced anti-tumor activity. The day after subcutaneous inoculation in the footpad with B16 melanoma, mice were freely fed the extract and were vaccinated with a tyrosinase-related protein 2_180–188 peptide. The peptide vaccine was repeated thrice weekly. Melanoma growth was significantly suppressed in mice treated with both the peptide vaccine and L.E.M. extract compared with mice treated with vaccine or extract alone, and the effect was CD8⁺ T cell-dependent. The combination therapy increased H-2K^b-restricted and B16 melanoma-reactive T cells in the draining lymph nodes and spleen. Flow cytometric and immunohistological analyses revealed that the combination therapy significantly decreased the percentage of Tregs in the draining lymph nodes and spleen of melanoma-bearing mice compared to treatment with vaccine or extract alone. Kinetic analyses of peptide-specific T cells and Tregs revealed that induction of peptide-specific T cells by the peptide vaccine alone was transient, but when combined with L.E.M. extract, it efficiently prolonged the duration of peptide-specific T cell induction without increasing the percentage of Tregs. These results indicate that combination therapy enhances peptide vaccine-induced anti-tumor activity due to attenuation of the increase in the percentage of Tregs in tumor-bearing hosts.     

Effects of the antlered form of Ganoderma lucidum on tumor growth and metastasis in cyclophosphamide-treated mice

We examined the alleviation of cyclophosphamide-induced immunodepression by the antlered form of Ganoderma lucidum (G. lucidum AF) and also evaluated the anti-tumor and anti-metastatic effects of G. lucidum AF in cyclophosphamide-treated mice. G. lucidum AF alleviated cyclophosphamide-induced decrease in body weight, natural killer (NK) activity, interferon (IFN)-gamma production, and cytotoxic T lymphocyte (CTL) activity, and inhibited the abnormal increase and decrease in interleukine (IL)-4 level due to cyclophosphamide administration. Post-treatment with cyclophosphamide and G. lucidum AF significantly inhibited tumor growth in MM 46-bearing mice. When Lewis lung carcinoma cells were injected into mice after a cyclophosphamide administration, metastasis of these cells to the lung was increased, but G. lucidum AF suppressed it. The anti-tumor and anti-metastatic effects of the combination of G. lucidum AF and cyclophosphamide might influence the modulatory effects of G. lucidum AF on both cellular and humoral immunity. These findings suggest that G. lucidum AF would be beneficial in alleviating the reduction of immune response by chemotherapeutic anti-cancer drugs.     

Chemical modification of ascorbic acid and evaluation of its lipophilic derivatives as inhibitors of secretory phospholipase A2 with anti-inflammatory activity

This investigation aims to evaluate the antitumor and antioxidant potential of Chrysaora quinquecirrha (sea nettle) nematocyst venom on Ehrlich ascites carcinoma (EAC) tumor model. Tumor was induced in mice by intraperitoneal injection of EAC cells. The antitumor effect of sea nettle nematocyst venom (SNV) peptide was evaluated by assessing in vitro cytotoxicity, survival time, hematological, and antioxidant parameters. Intraperitoneal injection of SNV peptide increased the survival time of the EAC-bearing mice. The SNV peptide brought back the altered levels of the hematological and antioxidant parameters in a dose dependent manner in EAC-bearing mice. The results were comparable to that of the result obtained from the animals treated with the standard drug 5-fluorouracil (20 mg/kg bw). Thus, present study revealed that SNV peptide possessed significant antitumor and antioxidant activity.     

Lymphocyte function in experimental African trypanosomiasis. IV. Immunosuppression and suppressor cells in the athymic nu/nu mouse

The role of T cells in the development and expression of antigen-nonspecific immunosuppression in experimental African trypanosomiasis was addressed. Nude ($\text{nu}\text{nu}$) C57BL/ 6 NIH mice and their thymus-bearing ($\text{nu}\text{+}$) littermates were infected with Trypanosoma rhodesiense and examined for suppression of splenic B-cell responses in vitro to the mitogen LPS. All animals developed splenic unresponsiveness to LPS. Further, both nu/nu and nu/ + infected mice displayed suppressor cell activity in their spleen cell populations upon transfer to normal uninfected mouse spleen cell cultures. On the basis of these findings we suggest that both the generalized immunosuppression and the development of suppressor cell activity in the spleens of mice infected with T. rhodesiense are T-independent processes.     

Fertility,Gestation Outcome and Parasite Congenital Transmissibility in Mice Infected with TcI,TcII and TcVI Genotypes of Trypanosoma cruzi

This work aims to compare the effects of acute or chronic infections with the T. cruzi genotypes TcI (X10 strain), TcII (Y strain) and TcVI (Tulahuen strain) on fertility, gestation, pup growth and the possible vertical transmission of parasites in BALB/c mice. The occurrence of congenital infection was evaluated by microscopic examination of blood and/or qPCR on blood and heart in newborn pups and/or older offspring submitted to cyclophosphamide-induced immunosuppression in order to detect possible cryptic congenital infection. Altogether, the results show that: i) for the three strains tested, acute infection occurring after the embryo implantation in the uterus (parasite inoculation 4 days before mating), or close to delivery (parasite inoculation on day 13 of gestation), prevents or severely jeopardizes gestation outcome (inducing pup mortality and intra-uterine growth retardation); ii) for the three strains tested, gestation during chronic infection results in intra-uterine growth retardation, whereas re-inoculation of TcVI parasites during gestation in such chronically infected mice, in addition, strongly increases pup mortality; iii) congenital infection remains a rare consequence of infection (occurring in approximately 4% of living pups born to acutely infected dams); iv) PCR, detecting parasitic DNA and not living parasites, is not convenient to detect congenial infection close to delivery; v) transmission of parasites by breast milk is unlikely. This study should encourage further investigations using other parasite strains and genotypes to explore the role of virulence and other factors, as well as the mechanisms of such effects on gestation and on the establishment of congenital infection.     

Biosynthesized nanosilver as anti-oxidant,anti-apoptotic and anti-inflammatory agent against Plasmodium chabaudi infection in the mouse liver

In recent years, the use of plant-mediated nanoparticle synthesis to combat infectious diseases has become increasingly significant. Malaria is one of the world's most infectious diseases caused by Plasmodium species. The antioxidant, anti-apoptotic, and anti-inflammatory properties of nanosilver biosynthesized from Indigofera oblongifolia leaf extracts (NS) against Plasmodium chabaudi infection of the mouse liver were investigated in this research. Male mice were infected with P. chabaudi infected erythrocytes then treated with NS for 7 days. The parasitemia was suppressed by approximately 24, 28, 47 and 75% on days 4, 5, 6 and 7 postinfection, respectively after treatment of mice with NS. Also, NS was able to regulate the leucocytes count and the IL1β and TNF-α-mRNA expression in mice. Ns could increase the antioxidant activity in liver of mice and was able to regulate the apoptotic genes, Bcl2 and Casp3. We showed that NS has antioxidant, anti-apoptotic, and anti-inflammatory properties when it was used to treat the livers of mice infected with P. chabaudi.     

Excessive immunosuppression by regulatory T cells antagonizes T cell response to schistosome infection in PD-1-deficient mice

Schistosomiasis is caused by parasitic flatworms known as schistosomes and affects over 200 million people worldwide. Prevention of T cell exhaustion by blockade of PD-1 results in clinical benefits to cancer patients and clearance of viral infections, however it remains largely unknown whether loss of PD-1 could prevent or cure schistosomiasis in susceptible mice. In this study, we found that S. japonicum infection dramatically induced PD-1 expression in T cells of the liver where the parasites chronically inhabit and elicit deadly inflammation. Even in mice infected by non-egg-producing unisex parasites, we still observed potent induction of PD-1 in liver T cells of C57BL/6 mice following S. japonicum infection. To determine the function of PD-1 in schistosomiasis, we generated PD-1-deficient mice by CRISPR/Cas9 and found that loss of PD-1 markedly increased T cell count in the liver and spleen of infected mice. IL-4 secreting Th2 cells were significantly decreased in the infected PD-1-deficient mice whereas IFN-γ secreting CD4⁺ and CD8⁺ T cells were markedly increased. Surprisingly, such beneficial changes of T cell response did not result in eradication of parasites or in lowering the pathogen burden. In further experiments, we found that loss of PD-1 resulted in both beneficial T cell responses and amplification of regulatory T cells that prevented PD-1-deficient T cells from unleashing anti-parasite activity. Moreover, such PD-1-deficient Tregs exert excessive immunosuppression and express larger amounts of adenosine receptors CD39 and CD73 that are crucial for Treg-mediated immunosuppression. Our experimental results have elucidated the function of PD-1 in schistosomiasis and provide novel insights into prevention and treatment of schistosomiasis on the basis of modulating host adaptive immunity.     

Augmentation of specific immune response against a syngeneic SV40-induced sarcoma in mice by depletion of suppressor T cells with cyclophosphamide.

When cyclophosphamide was administered to mice before immunization with syngeneic SV40-transformed cells, the specific immune response elicited, as was measured by the tumor cell neutralization assay with a syngeneic SV40-induced sarcoma, was stronger and lasted longer as compared to the response generated in non-cyclophosphamide-treated mice. The augmentation effect of the drug was dependent on cyclophosphamide concentration, being optimal at 100 mg/kg, and on the time of drug administration in relation to antigen immunization, being optimal at 2–4 days before antigen administration. Transfer of T cells from normal syngeneic mice to drug-treated animals abolished the cyclophosphamide-induced augmentation of immune response. These results implied that cyclophosphamide-sensitive T cells suppressed the in vivo generation of specific effector T cells against SV40-induced sarcoma.     

The effect of rabbit anti-mouse brain-associated theta serum on the immunologic responsiveness of AKR mice

Rabbit anti-C3H mouse brain-associated antiserum (BA-θ) was tested for its effect on the immunologic responsiveness of preleukemic and leukemic AKR mice to sheep erythrocytes. This BA-θ antiserum was cytotoxic in vitro for both C3H and for AKR thymocytes, and was immunosuppressive in vivo. Greater immunosuppression was effected by the antiserum in preleukemic AKR mice than in leukemic animals. Control rabbit serum also was cytotoxic in vitro and immunosuppressive in vivo, but this activity was removed by absorption with homologous erythrocytes and liver tissue, and with agarose. Conversely, absorption of the rabbit anti-BA-θ serum had no effect on either the in vitro cytotoxic activity, or on the in vivo immunosuppression.     

3,4-Dihydroxyphenethyl nitrate with nitric oxide releasing,antioxidant, hypoglycemic and hypolipidemic effects

Nitric oxide (NO) dysfunction, oxidative stress, and dyslipidemia are main risk factors associated with the pathophysiology of diabetic complications. In this study, 3,4-dihydroxyphenethyl nitrate (HT-ONO₂) was designed, synthesized and evaluated, which incorporated hydroxytyrosol (HT) and nitrate. HT-ONO₂ significantly exhibited hypoglycemic activity after oral administration to diabetic mice induced by streptozocin (STZ). HT-ONO₂ also potently decreased plasma triglyceride (TG), total cholesterol (TC) in hyperlipidemia mice induced by Triton WR 1339. Meanwhile, HT-ONO₂ displayed NO-releasing and antioxidant activity both in diabetic and hyperlipidemia mice and in vitro. Moreover, HT-ONO₂ shown definite vasodilation and α-glucosidase inhibition activity in vitro. The results suggested that the hybrid hydroxytyrosol-based nitrate with NO supplement, antioxidant, hypoglycemia and hypolipidemia provided a potential multi-target agent to ameliorate the diabetes mellitus and its complications.     

A polysaccharide from Sargassum fusiforme protects against immunosuppression in cyclophosphamide-treated mice

A water-soluble polysaccharide (SFPS) isolated from Sargassum fusiforme was purified by DEAE-52 cellulose anion-exchange and Sephadex G-200 gel filtration chromatography. The high performance gel permeation chromatography (HPGPC) analysis showed that the average molecular weight (Mw) of SFPS was 299kDa. The SFPS was composed of d-fucose, l-xylose, d-mannose and d-galactose in a molar ratio of 5.9:1.0:2.3:2.2. The results showed that SFPS stimulated proliferation and the cytokines (IL-2, IL-6 and IFN-γ) secretion of splenic lymphocytes in cyclophosphamide-induced immunosuppressed mice. SFPS markedly increased the phagocytic rates and cytokines (IL-2, IL-6 and TNF-α) secretion of peritoneal macrophages. Administration of SFPS significantly raised spleen index. It could act as an efficacious adjacent immunopotentiating therapy or an alternative means in lessening chemotherapy-induced immunosuppression, and also can be utilized as immunostimulants for food and pharmaceutical industries.     

Antioxidant,hepatoprotective and cytotoxic effects of icetexanes isolated from stem-bark of Premna tomentosa

The study investigates the antioxidant, hepatoprotective and antiproliferative effects of novel icetexane diterpenoids (ice 1–4) isolated from hexane extract of stem bark of Premna tomentosa. A549, HT-29, MCF-7, MDA-MB-231, A431 cells were used to assess the antiproliferative activity by MTT assay. Cell death induced by apoptosis was determined by morphological assessment studies using acridine orange/ethidium bromide staining (dual staining), mitochondrial potential measurement by JC-1 staining, and cell cycle analysis by propidium iodide staining method by Muse cell analyser. Anti oxidant activity was investigated by in vitro assays such as DPPH, nitric oxide and superoxide scavenging activities. Hepatoprotective activity was determined in vitro with HepG2 cells and in vivo by tBHP induced hepatic damage mice model. Based on the in vitro cytotoxic assays and morphological assessment studies using fluorescence microscopic study (acridine orange and ethidium bromide double staining) and mitochondrial potential measurements, it was found that ice 2 and 3 possess good antiproliferative effect via mitochondrial mediated apoptosis in human lung and breast cancer cells. Results of in vitro antioxidant studies demonstrated that ice-4 has showed good antioxidant activity. The restoration of serum levels of SGOT, SGPT and ALKP, liver GSH status and reduction or inhibition of lipid peroxidation in liver of tBHP intoxicated mice after administration of ice-4 at dose of 250 mg/kg indicated its potential use for hepatoprotective activity.     

Dietary eicosapentaenoic acid prevents systemic immunosuppression in mice induced by UVB radiation.

Moison, R. M. W. and Beijersbergen van Henegouwen, G. M. J. Dietary Eicosapentaenoic Acid Prevents Systemic Immunosuppression in Mice Induced by UVB Radiation. Radiat. Res. 156, 36-44 (2001).Reactive oxygen species (ROS) contribute to the immunosuppression induced by UVB radiation. Omega-3 fatty acids in fish oil, e.g. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can modulate immunoresponsiveness, but because of their susceptibility to ROS-induced damage, they can also challenge the epidermal antioxidant defense system. The influence of dietary supplementation with different omega-3 fatty acids on systemic immunosuppression induced in mice by UVB radiation was studied using the contact hypersensitivity response to trinitrochlorobenzene. In an attempt to study the mechanisms involved, UVB-radiation-induced changes in epidermal antioxidant status were also studied. Mice received high-fat (25% w/w) diets enriched with either oleic acid (control diet), EPA, DHA, or EPA + DHA (MaxEPA). Immunosuppression induced by UVB radiation was 53% in mice fed the oleic acid diet and 69% in mice fed the DHA diet. In contrast, immunosuppression was only 4% and 24% in mice fed the EPA and MaxEPA diets, respectively. Increased lipid peroxidation and decreased vitamin E levels (P < 0.05) were found in unirradiated mice fed the MaxEPA and DHA diets. For all diets, exposure to UVB radiation increased lipid peroxidation (P < 0.05), but levels of glutathione (P < 0.05) and vitamin C (P > 0.05) decreased only in the mice given fish oil. UVB irradiation did not influence vitamin E levels. In conclusion, dietary EPA, but not DHA, protects against UVB-radiation-induced immunosuppression in mice. The degree of protection appears to be related to the amount of EPA incorporated and the ability of the epidermis to maintain an adequate antioxidant level after irradiation.