Effects of Lactobacillus rhamnosus ATCC 7469 on Different Parameters Related to Health Status of Rainbow Trout (Oncorhynchus mykiss) and the Protection Against Yersinia ruckeri.

In the current study, we investigated the effect of a probiotic bacterium (Lactobacillus rhamnosus ATCC 7469) microencapsulated with alginate and hi-maize starch and coated with chitosan on improving growth factors, body composition, blood chemistry, and the immune response of rainbow trout (initial weight: 18.41 ± 0.32 g). Four experimental diets were formulated to feed fish for 60 days. They were control diet without any additive (C), diet added with beads without probiotic (E), a probiotic sprayed to the diet (L.r), and encapsulated probiotic supplemented diet (E-L.r). The results indicated that feeding with E-Lr significantly improved weight gain (84.98 g) and feed conversion ratio (0.95) compared to the other groups (P < 0.05). Also, fish fed E-Lr diet had a significantly higher value of whole-body protein (17.51%), total protein in the blood (4.98 g/dL), lysozyme (30.66 U/mL), alternative complement pathway hemolytic activity (134 U/mL), superoxide dismutase (203 U/mg protein), and catalase (528.33 U/mg protein) (P < 0.05) as compared to those fed the control diet. Similarly, a higher relative expression of immune-related genes such as interleukin-1 (Il-1) and tumor necrosis factor-alpha (TNF-1α) were reported in those fed E-L.r and L.r diets respectively. Interestingly, the fish fed dietary E-L.r had a significantly lower value of lipid in the whole body (4.82%) and cholesterol in the blood (160.67%) in comparison with those fed the control diet (P < 0.05). At the end of the experiment, all groups were challenged by Yersinia ruckeri where the survival rate of rainbow trout fed dietary E-L.r (70.36%) was statistically higher than that of the others (P < 0.05). Overall, the results suggested that encapsulated probiotic Lact. rhamnosus ATCC 7469 acted better than unencapsulated probiotic and has a potential to improve growth performance, flesh quality, and the immune response of rainbow trout.

Effects of orange peels derived pectin on innate immune response, disease resistance and growth performance of Nile tilapia (Oreochromis niloticus) cultured under indoor biofloc system.

The present study investigates the effects of orange peels derived pectin (OPDP) on skin mucus and serum immune parameters, disease resistance and growth performance of O. niloticus cultured under indoor biofloc system. Six hundred Nile tilapia (average weight 9.09 ±â€¯0.05 g) were distributed into 15 fiber tanks (300 L per tank) assigned to five treatments repeated in triplicate. Fish were fed experimental diets contain different levels OPDP as follows: 0 (control in clear water), 0 (control in biofloc system), 5, 10, and 20 g kg-1 OPDP for 8 weeks. At weeks 4 and 8 post feeding, skin mucus lysozyme (SMLA), peroxidase activities (SMPA), serum lysozyme (SL), serum peroxidase (SP), alternative complement (ACH50), phagocytosis (PI), and respiratory burst activities (RB) as well specific growth rate (SGR), weight gain (WG), final weight (FW), and feed conversion ratio (FCR) were measured. Also, resistance against Streptococcus agalactiae was assessed after 8 weeks post-feeding. Nile tilapia fed OPDP supplemented diets had significantly higher SMLA and SMPA compared to the controls (P < 0.05). The maximum values were observed in tilapia fed 10 g kg-1 OPDP followed by 5 and 20 g kg-1 OPDP. Nevertheless, no significant differences were observed between these two supplemented diets and between the control groups (P > 0.05). Regarding the serum immunological parameters, dietary inclusion of 10 g kg-1 OPDP showed significant higher SL and PI than other supplemented groups and control groups (P < 0.05). However, no significant differences were observed in SL and PI of fish fed 5 and 20 g kg-1 OPDP (P > 0.05). Dietary administration of OPDP significantly increased SP and ACH50 compared to the controls (P < 0.05), regardless of inclusion level. Additionally, non-significant change was found in RB of OPDP fed fish when compared with the controls (P > 0.05). The challenge test revealed that relative percent of survival (RPS) in OPDP treatments were 45.45%, 81.82%, 50%, respectively. The highest RPS was noticed in fish fed 10 g kg-1 OPDP. Furthermore, dietary administration of OPDP significantly improved SGR, WG, FW, and FCR (P < 0.05). Overall, the present findings suggested that OPDP can be taken into account as functional feed additives for O. niloticus.

Flavonol glycosides and other phenolic compounds from Viola tianshanica and their anti-complement activities.

CONTEXT: Viola tianshanica Maxim. (Violaceae) is a perennial herb distributed in Central Asia, especially in the Xinjiang Uygur Autonomous Region (XUAR) of China. Preliminary study showed that the ethanol extract of the herb exhibited the anti-complement activity against the classical pathway, but the active components responsible for this capacity remain unknown and are yet to be studied. OBJECTIVE: The objective of this study was the isolation and identification of the anti-complement constituents of V. tianshanica. MATERIALS AND METHODS: The ethyl acetate and n-butanol fractions from the ethanol extract of V. tianshanica were purified. The structures of the isolates were identified by spectroscopic methods, and comparing their spectral data with those reported in the literature. All the isolates (0.02-2.50 mg/mL) were evaluated for their anti-complement activity against the classical and alternative pathways. RESULTS: Twenty-one phenolic compounds including 15 flavonol O-glycosides (1-15), one flavone 6,8-di-C-glycoside (16), one flavone aglycone (17), and four phenolic acid derivatives (18-21) were isolated and identified. Bioassay showed that 11 compounds inhibited the classical pathway and the alternative pathway with CH50 and AP50 values of 0.113-1.210 mM and 0.120-1.579 mM, respectively. Preliminary mechanistic study using complement-depleted sera demonstrated that 1 acted on C1q, C2, C4, and C9 components, 16 on C1q, C4, and C5, and 21 on C1q, C3, C4, and C9. CONCLUSION: All isolated compounds except 1 and 10 were reported for the first time from V. tianshanica. Compound 16 is the first flavone C-glycoside isolated from the herb. Flavonol O-glycosides and phenolic acids contributed the anti-complement activity of the herb.

The effect of Pediococcus acidilactici bacteria used as probiotic supplement on the growth and non-specific immune responses of green terror, Aequidens rivulatus.

A 56-day feeding trial was conducted on a species of ornamental fish called green terror (Aequidens rivulatus) (0.388 ± 0.0021 g) to assess the effect of probiotic bacteria, Pediococcus acidilactici on the growth indices and innate immune response. The fish were randomly allocated into 9 oval tanks (120 l) at a density of 60 fish per tank. The experimental diets were comprised of the control (C), C complemented with fish oil (O) and the probiotic and fish oil (PA) and fed ad lib twice a day. The growth indices (specific growth rate (SGR), feed conversion ratio (FCR) and immunological indices of fish fed the diets including lysozyme activity, total immunoglobulin and alternative complement activity were measured. The Fish fed with the diet containing P. acidilactici (PA) displayed significantly (P < 0.05) higher final weight (3.25 ± 0.065 g), weight gain (830.94 ± 9.46%), SGR (3.53 ± 0.02%/day) and lower FCR (1.45 ± 0.011) compared to those of other experimental diets. Total immunoglobulin (10.05 ± 0.12 µg/ml), lysozyme activity (4.08 ± 0.85 µg/ml) and alternative complement activity (2.65 ± 0.12 U/ml) in the serum of PA fed fish showed significant compared to other treatments (P < 0.05). The results showed positive effects of P. acidilactici as a potent probiotic on growth indices and non-specific immune system of green terror.

Innate immune responses and efficacy of using mushroom beta-glucan mixture (MBG) on orange-spotted grouper, Epinephelus coioides, aquaculture.

This study attempts to describe the effects of innate immunity responses and field application of mushroom beta-glucan mixture (MBG) in cultured orange-sported grouper, Epinephelus coioides. Chemical analysis for MBG showed that the mixture contains 34.06% of macro-molecular polymers with bio-active linkage such as 3-; 3,4- and 4,6-glucopyranosyl and 6-linked galactopyranosyl residues. Study performed on the innate immunity showed that oral ingestion of MBG at 1.0 g and 2.0 g per kilogram of feed levels may significantly enhance the lysozyme activity, alternative complement activity, phagocytic activity and respiration burst of the experimental groupers. Observation on the experimental challenge of pathogen showed that uses of MBG at 0.1% and 0.2% levels in feed might significantly enhance the protection of grouper against Vibrio alginolyticus. Field trials performed on short and long-term culture showed that feeding of diet containing 0.1% or 0.2% of MBG may significantly enhance the survival of cultured groupers up to 16% when compared with those obtained from controls.

Potential probiotic Lactobacillus plantarum VSG3 improves the growth, immunity, and disease resistance of tropical freshwater fish, Labeo rohita.

The study evaluated the effects of dietary doses of Lactobacillus plantarum VSG3 on the growth performance, immunity, and disease resistance of Labeo rohita juveniles against Aeromonas hydrophila infection. Fish (mean body weight 60 g) were fed with diet containing 0 (control), 10(6), 10(8), 10(10) cfu g(-1)L. plantarum VSG3 for 60 days. Various growth and immune parameters were examined at 30 and 60 days of post-feeding. Fish were challenged with A. hydrophila 60 days post-feeding and mortalities were recorded over 10 days post-infection. Results showed that administration of VSG3 for 60 days had significant effects (P < 0.05) on the specific growth rate (SGR) and feed utilization efficiency of L. rohita. Dietary administration of L. plantarum VSG3 significantly increased the serum lysozyme and alternative complement pathway (ACP) activities, phagocytosis and respiratory burst activity in L. rohita throughout the experimental period. The highest superoxide dismutase (SOD) activity (P < 0.05) was observed in the fish group fed diet containing VSG3 at 10(8) cfu g(-1). The serum IgM levels were significantly higher in the experimental groups compared to the control group after 30 days of feeding; but, the result was opposite after 60 days of feeding. Further, fish fed the diet containing 10(8) cfu g(-1)L. plantarum VSG3 had significantly higher (P < 0.05) post-challenge survival rate (77.7%). These results collectively suggest that dietary supplementation of L. plantarum VSG3 at 10(8) cfu g(-1) to L. rohita is optimal for enhancing the growth, immunity, and disease resistance against A. hydrophila infection.

Effect of tricainemethanesulfonate (MS222), clove oil and electro-anaesthesia on respiratory burst activity in whole blood and serum alternative complement response in rainbow trout (Oncorhynchus mykiss), during the narcosis stage.

There is a little available information on the suppressive effect of anaesthesia on immune response in fish, especially electro-anaesthesia. In the present study, two anaesthetics, MS222 (50 ppm), clove oil (25 ppm), and electro-anaesthesia were tested in rainbow trout (Oncorhynchus mykiss) during the narcosis stage in order to observe their effects on the innate immune system. The results showed that electro-anaesthesia reduces light emission in chemiluminescence assay both 1 and 24 h post anaesthesia. Clove oil and MS222 decreased light emission 24 h post anaesthesia. In addition, clove oil, MS222 and electro-anaesthesia had no effect on alternative complement (ACH50) response. From the perspective of aquaculture practice, these data show that the type of anaesthesia should be taken into account to avoid possible immunosuppression in rainbow trout.

Recurrent dense deposit disease after renal transplantation: an emerging role for complementary therapies.

Dense deposit disease is a rare glomerulonephritis caused by uncontrolled stimulation of the alternative complement pathway. Allograft survival after kidney transplantation is significantly reduced by the high rate of disease recurrence. No therapeutic interventions have consistently improved outcomes for patients with primary or recurrent disease. This is the first reported case of recurrent dense deposit disease being managed with eculizumab. Within 4 weeks of renal transplantation, deteriorating graft function and increasing proteinuria were evident. A transplant biopsy confirmed the diagnosis of recurrent dense deposit disease. Eculizumab was considered after the failure of corticosteroid, rituximab and plasmapheresis to attenuate the rate of decline in allograft function. There was a marked clinical and biochemical response following the administration of eculizumab. This case provides the first evidence that eculizumab may have a place in the management of crescentic dense deposit disease. More information is necessary to clarify the effectiveness and role of eculizumab in dense deposit disease but the response in this patient was encouraging. The results of clinical trials of eculizumab in this condition are eagerly awaited.

Effects of dietary ß-1,3-glucan, chitosan or raffinose on the growth, innate immunity and resistance of koi (Cyprinus carpio koi).

This study was performed to determine the efficacy of three immunomodulators viz., ß-1,3 glucan, chitosan and raffinose on the innate immune response of koi, Cyprinus carpio koi. Kois were divided into 4 groups and each group was fed with diets supplemented with or without immunostimulant for 56 days. Total leukocyte counts (WBC), the non-specific humoral (lysozyme, alternative complement pathway and superoxide dismutase) and cellular (phagocytic capacity and respiratory burst activity) responses were determined and compared with controls (no supplement) after 7, 14, 21 and 56 days of feeding. The results of 8 weeks feeding trial showed that ß-1,3 glucan supplementation significantly enhanced koi growth, whereas other immunostimulants did not. Variation in the levels of responses was evident among different supplements. Compared with chitosan or raffinose, ß-1,3 glucan could maintain the immunity of kois at a higher level during the experimental period. However, continuously applying ß-1,3 glucan, chitosan or raffinose into the diet caused immunity fatigue in koi. No significant change in alternative complement pathway (ACP) activity was observed for any of the three supplements over the four different periods. After feeding for 14 days, the total leukocyte count (WBC), respiratory burst activity and superoxide dismutase (SOD) activity of the kois fed with chitosan or raffinose continuously remained relatively unchanged, subsequently decreased on the 56th day, but SOD did not. Meanwhile, lysozyme activity was no longer significantly higher on the 7th day, and for phagocytic capacity on the 14th day. After 56 days, these three immunostimulants groups also exhibited a decrease in the cumulative symptom rates compared to the controls when challenged with Aeromonas veronii. These results indicated that dietary intake containing immunostimulants could enhance the immune responses of koi and improve its resistance to infection by A.veronii. Especially supplementation with ß-1,3 glucan to the kois for 56 days showed considerable improvement in the growth, survival and immune response of the kois.

Differential cardioprotective effects of salvianolic acid and tanshinone on acute myocardial infarction are mediated by unique signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Salvianolic acid (SAL) and tanshinone (TAN) are major hydrophilic and lipophilic compounds, respectively, from one herbal medicine, Danshen, which has been widely and successfully used for treating cardiovascular diseases in Asian countries. Because few studies have reported different molecular mechanisms between the different compounds in same herb, we investigate if separate molecular pathways are involved in cardioprotective effect by different active components of Danshen. MATERIALS AND METHODS: We used an acute myocardial infarction (MI) model to compare the cardioprotective effects of SAL and TAN in rats. Both infarct size and echocardiographic response were evaluated at 3, 7, 14 and 28 days after surgery. Genes involved in ischemic injury and in responses to SAL or TAN treatment in ischemic hearts were identified by microarray analysis and verified by quantitative real-time RT-PCR. RESULTS: Results showed that both SAL and TAN delay the development of ischemia by decreasing infarct size and improving systolic function post MI. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated different kinetics and gene expression profiles by SAL and TAN. SAL acts in a later period after ischemia, and its effect is probably mediated by downregulation of genes involved in oxidative stress, certain G-protein coupled receptor activities and apoptosis. On the other hand, TAN acts relatively early after ischemic injury and its effect is at least in part mediated by inhibition of intracellular calcium, cell adhesion and alternative complement pathway. Strikingly, we found that TAN, a recently identified member of selective estrogen receptor modifier (SERM), indeed regulates genes known to be involved in estrogen metabolism post MI. CONCLUSIONS: Although both SAL and TAN contribute to the cardioprotective effect of Danshen, there are significant mechanistic and temporal differences between the two: TAN acts at an early stage after ischemic injury mainly by inhibition of intracellular calcium and cell adhesion pathways whereas SAL acts mainly by down-regulating apoptosis.

Epigallocatechin-3-gallate (EGCG) affects the antioxidant and immune defense of the rainbow trout, Oncorhynchus mykiss.

Epigallocatechin-3-gallate (EGCG), a very potent antioxidant derived from green tea, was compared with vitamin E in terms of its effects on antioxidant defense and immune response of rainbow trout, by means of a feeding trial of eight weeks. Two of the experimental diets were supplemented with EGCG at either 20 or 100 mg kg(-1) diet (which contained only 30% of the intended levels) and the third was provided with 100 mg kg(-1) vitamin E but not EGCG. The control diet was not supplemented with the test components. Observation of tissue levels indicated that the high amount of EGCG helped to increase the availability of the lipid-soluble antioxidant vitamin E. The lower levels of lipid hydroperoxide in the liver of fish fed the higher amount of EGCG suggested that it was an effective antioxidant. Considering the immune indices, EGCG and vitamin E at 100 mg (actual amounts 31.9 and 94.1 mg kg(-1) diet, respectively) had identical capabilities in improving phagocytic activity and controlling hydrogen peroxide production by leucocytes. However, EGCG could possibly be more effective at enhancing serum lysozyme activity and the alternative complement activity. This work revealed the potential of EGCG as an antioxidant and an immunostimulant for rainbow trout, at least at the inclusion level of 32 mg kg(-1) diet.

Improving therapeutic efficacy of a complement receptor by structure-based affinity maturation.

CRIg is a recently discovered complement C3 receptor expressed on a subpopulation of tissue-resident macrophages. The extracellular IgV domain of CRIg (CRIg-ECD) holds considerable promise as a potential therapeutic because it selectively inhibits the alternative pathway of complement by binding to C3b and inhibiting proteolytic activation of C3 and C5. However, CRIg binds weakly to the convertase subunit C3b (K(D) = 1.1 microm), and thus a relatively high concentration of protein is required to reach nearly complete complement inhibition. To improve therapeutic efficacy while minimizing risk of immunogenicity, we devised a phage display strategy to evolve a high affinity CRIg-ECD variant with a minimal number of mutations. Using the crystal structure of CRIg in complex with C3b as a guide for library design, we isolated a CRIg-ECD double mutant (Q64R/M86Y, CRIg-v27) that showed increased binding affinity and improved complement inhibitory activity relative to CRIg-ECD. In a mouse model of arthritis, treatment with a Fc fusion of CRIg-v27 resulted in a significant reduction in clinical scores compared with treatment with an Fc fusion of CRIg-ECD. This study clearly illustrates how phage display technology and structural information can be combined to generate proteins with nearly natural sequences that act as potent complement inhibitors with greatly improved therapeutic efficacy.

Complement activation by carotenoid derived aldehydes in cultured human vein epithelial cells.

This study was designed to determine the complement activation effects of carotenoid-derived aldehydes (CDA) on cultured human umbilical vein endothelial cells (HUVEC). A dose-dependent complement activation upon incubation of HUVEC with CDA was observed. Interestingly, the data showed that the alternative pathway was not activated. In addition, upon CDA treatment a significant number of apoptotic cells was also observed. The results revealed that CDA could activate the complement by way of the classical pathway. The study suggests that high carotenoid supplementation for the treatment of coronary heart disease should be used cautiously.

Anticomplementary principles of a Chinese multiherb remedy for the treatment and prevention of SARS.

AIM OF THE STUDY: To elucidate the anticomplementary principles of a Chinese multiherb remedy used for the treatment and prevention of SARS, which contains five ingredients of Herba Houttuyniae, Flos Chrysanthemi Indici, Herba Artemisiae Scopariae, Herba Eupatorii and Fructus Tsaoko. MATERIALS AND METHODS: The anticomplementary activity was evaluated from hemolytic assays through the classical pathway (CP) and the alternative pathway (AP) of complement system in vitro. Compounds were isolated using bioactivity-guided fractionation and tested in vitro for their complement-inhibiting properties on the CP and AP. HPLC-DAD-ESI-MS was used to assign the isolated compounds in the five ingredient herbs. RESULTS: 15 compounds, including chlorogenic acid (1), rutin (2), hyperoside (3), p-hydroxyacephenone (4), scopoletin (5), quercitrin (6) (3R,4R,6S)-3,6-dihydroxy-1-menthene (7), acaciin (8), scoparone (9), luteolin (10), quercetin (11), apigenin (12), acacetin (13), aristolactam (14), and apigenin-7,4'-dimethyl ether (15) were isolated and identified. Nine flavonoids (2, 3, 6, 8, 10-13, 15) were found to show inhibitory effects towards the CP and AP of complement system, luteolin (10) was the most potent with the CH50 and AP50 values of 0.19 and 0.17 mM. The bioactive flavonoids were mainly derived from Herba Houttuyniae, Flos Chrysanthemi Indici and Herba Artemisiae Scopariae. CONCLUSIONS: A Chinese multiherb remedy used for the treatment and prevention of SARS has robust inhibitory effect on complement system through the CP and AP, and its anticomplementary activity could be attributed to the flavonoids present in some ingredient herbs. Luteolin could be a potential anticomplementary agent.

Isolation and characterization of biopolymers extracted from the bark of Acanthopanax sessiliflorus and their anticomplement activity.

The crude biopolymer (AS-S1) and endo-biopolymer (AS-S2) were isolated from the dry stem bark of Acanthopanax sessiliflorus and tested for anti complement activity. The two potent anticomplement biopolymers, AS-1 and AS-2-Fr.I, were isolated by the combination of ion-exchange chromatography and gel filtration methods from the endo-biopolymers (AS-S2). The anticomplement activity of AS-1 (MW 12 kDa) and AS-2-Fr.I (MW 180 kDa) were found to be 84.4% and 100.0%, respectively, at the concentration of 25 microg/ml. Activated pathway of the complement system occurred in both classical and alternative pathways, as evidenced by crossed immunoelectrophoresis (CIEP), where a major pathway was detected to be the classical one. It was found that the anticomplement activities of the periodate oxidized were decreased significantly, but those of pronase digested biopolymers of AS-1 and AS-2-Fr.I were decreased very little. The AS-1 contained 2,4,6-tri-O-methyl-D-glucitol, 2,3,6-tri-O-methyl-D-glucitol, and 2,3,6-tri-O-methyl-D-galacitol, which indicated that AS-1 contained a (1 --> 3), (1 --> 4)-linked glucopyranosyl residue and a (1 --> 4)-linked galactosyl residue. AS-2-Fr.I contained mainly 2,4-di-O-methyl-D-mannitol and 2,3,4-tri-O-methyl-D-galacitol, which contained (1 --> 3), (1 --> 6) linked mannosyl and (1 --> 6) linked galactosyl residues.

Effect of the extract of the tamarind (Tamarindus indica) fruit on the complement system: studies in vitro and in hamsters submitted to a cholesterol-enriched diet.

This work evaluated a crude hydroalcoholic extract (ExT) from the pulp of the tamarind (Tamarindus indica) fruit as a source of compounds active on the complement system (CS) in vitro. ExT, previously characterized by other authors, had time and concentration dependent effects on the lytic activity of the CS. The activity of 0.8 mg/mL of the extract on the classical/lectin pathways (CP/LP) increased after 30 min of pre-incubation, while that of the alternative pathway (AP) decreased after 15 min at 1mg/mL. Since the CS is a mediator of inflammation, studies were also made in vivo, taking advantage of a model of hypercholesterolemia in hamsters to investigate the role of CS in the phase preceding the inflammatory process of atherosclerosis. Hamsters submitted to a diet rich in cholesterol showed increased lytic activity of the CP/LP and AP after 45 days. The activity levels of C2 and factor B components on respectively, classical/lectin and alternative pathways of the CS also increased. Early events cooperating to trigger the process of atherosclerotic lesions are not completely understood, and these alterations of complement may participate in these events. When treatment with a diet rich in cholesterol was associated to the furnishing of ExT, evaluation of complement components and complement lytic activity showed values similar to those of the controls, showing that treatment with ExT blocked the increase of complement activity caused by the cholesterol-rich diet. By itself, ExT had no effect on the complement system in vivo. ExT activity on the CS may be of interest for therapy and research purposes.

Effects of dietary beta-1, 3 glucan on innate immune response of large yellow croaker, Pseudosciaena crocea.

The present study was conducted to investigate the effects of dietary beta-1, 3 glucan on the innate immune response and protection against Vibrio harveyi infection in large yellow croaker, Pseudosciaena crocea. A basal diet was supplemented with 0% (control), 0.09% (low) and 0.18% (high) beta-1, 3 glucan to formulate three experimental diets. Each diet was randomly allocated to triplicate groups of fish in floating sea cages (1.5 x 1.5 x 2.0m), and each cage was stocked with 100 fish (initial average weight 9.75+/-0.35 g). Fish were fed twice daily (05:00 and 17:00) to apparent satiation for 8 weeks. The results of 8 weeks feeding trial showed that low glucan supplementation (0.09%) significantly enhanced fish growth, whereas high supplementation (0.18%) did not. The serum lysozyme activity was significantly increased with the increase of dietary glucan (P < 0.05), and fish fed the diet with high glucan had significantly higher lysozyme activity compared with low glucan. There were no significant differences in alternative complement pathway (ACP) activity between fish fed diets with and without supplementation of glucan. The phagocytosis percentage (PP) and respiratory burst activity in fish fed the diet with 0.09% glucan were significantly higher than those in fish fed with the control diet (P < 0.05), but both immunological parameters significantly decreased in fish fed the diet with high supplementation compared with low supplementation and no significant difference was observed between the control and high supplementation groups. The challenge experiment showed that fish fed the diet with low glucan had significantly lower cumulative mortality compared with the control and high glucan groups (P < 0.05), but no significant difference was observed between the control and high supplementation groups. These results suggested that low glucan could enhance growth and innate immunity of large yellow croaker with an 8-week oral administration, but higher supplementation did not influence growth, or further improve immunity of large yellow croaker.

The immunostimulatory effects of sodium alginate and iota-carrageenan on orange-spotted grouper Epinephelus coicoides and its resistance against Vibrio alginolyticus.

The lysozyme activity, alternative complement activity (ACH50), respiratory burst, SOD (superoxide dismutase) activity and phagocytic activity of orange-spotted grouper Epinephelus coicoides were examined when the fish were injected intraperitoneally with sodium alginate at 10, 20, 30mgkg-1 and iota-carrageenan at 10, 20, 30mgkg-1, respectively after 24, 72 and 120 h. Serum ACH50 increased directly with dose after 24 and 72 h for both sodium alginate and iota-carrageenan treatments. The fish that received sodium alginate at 20mgkg-1 after 24 and 72 h, and the fish that received iota-carrageenan after 72 and 120 h showed significantly increased respiratory burst, SOD activity and phagocytic activity, respectively. In another experiment, E. coicoides which had been injected individually with sodium alginate and iota-carrageenan at 10, 20, 30mgkg-1, were challenged with Vibrio alginolyticus at 1.8x10(9) colony-forming units (cfu)fish-1 and then placed in seawater of 33 per thousand. The survival of fish that received sodium alginate at 20mgkg-1, and the fish that received iota-carrageenan at 30mgkg-1 was significantly higher than that of fish which received saline and the control fish after 48 h as well as at the termination of the experiment (120 h after the challenge). It is therefore concluded that E. coicoides which received sodium alginate at 20mgkg-1 or iota-carrageenan at 30mgkg-1 increased the non-specific immune response and resistance from V. alginolyticus infection.

Immunomodulatory activity and chemical characterisation of sangre de drago (dragon's blood) from Croton lechleri.

The immunomodulatory activity of the latex from Croton lechleri (sangre de drago) was determined by in vitro assays. Classical (CP) and alternative (AP) complement pathways activities were determined in human serum. Intracellular generation of reactive oxygen species (ROS) by human polymorphonuclear leukocytes (PMNs) and monocytes, and phagocytosis of opsonised fluorescent microspheres were measured by flow cytometry. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Activity on proliferation of murine lymphocytes was also investigated. In addition, anti-inflammatory activity was assayed in vivo by carrageenan-induced rat paw oedema test. Some of the activities were compared with those of the isolated alkaloid taspine. Sangre de drago from Croton lechleri showed immunomodulatory activity. It exhibited a potent inhibitory activity on CP and AP of complement system and inhibited the proliferation of activated T-cells. The latex showed free radical scavenging capacity. Depending on the concentration, it showed antioxidant or prooxidant properties, and stimulated or inhibited the phagocytosis. Moreover, the latex has strong anti-inflammatory activity when administered i. p. Taspine cannot be considered the main responsible for these activities, and other constituents, probably proanthocyanidins, should be also involved.

Clionasterol: a potent inhibitor of complement component C1.

Clionasterol (1a), clionasterol monoacetate (1b) and 5alpha,8alpha-epidioxy-24alpha-ethylcholest-6-en-3-ol (2), isolated from the marine sponge Xestospongia exigua, and beta-sitosterol (3) were tested for their influence on the classical (CP) and alternative (AP) pathways of activation of the human complement system in vitro. All the sterols inhibited the CP in a dose-dependent manner but no detectable effect was observed in the AP even at concentrations of 400 microM. Clionasterol was found to be a potent inhibitor of CP (IC50 = 4.1 microM) being ten-fold more active than beta-sitosterol. The presence of the epidioxy group on C-5 and C-8 of compound 2 caused a pronounced decrease of the inhibitory effect. Mechanistic studies on the anticomplementary effect of clionasterol revealed that it interferes with the complement component C1.