BackgroundRecently, we have highlighted the immunomodulatory activity of the standardized extracts of Phyllanthus amarus and P. urinaria. The present study was carried out to correlate between the prevalent constituents of the herbs and their inhibitory effects on phagocytic activity of human neutrophils.MethodsThe compounds, gallic acid, ellagic acid, corilagin, geraniin, phyllanthin and hypophyllanthin were identified and quantitatively analyzed in the extracts of Phyllanthus amarus and P. urinaria obtained from Malaysia and Indonesia by using a validated reversed phase high performance liquid chromatography (RP-HPLC) method. The standardized extracts and the pure compounds were evaluated for their effects on chemotaxis, β2 integrin (CD18) expression, phagocytosis and chemiluminescence of human phagocytes. Chemotactic activity was assessed using the Boyden chamber technique, inhibition of CD18 expression and phagocytic ability were tested with the aid of flow cytometry, while effect on the respiratory burst was investigated using a luminol-based chemiluminescence assay.ResultsAll plant extracts strongly inhibited migration of the phagocytes with the Malaysian P. amarus depicting the highest inhibitory activity. Amongst the compounds tested, geraniin demonstrated the strongest inhibitory activity on chemotaxis of polymorphonuclear leukocytes (PMNs) and monocytes with IC50 values of 1.09 and 1.69 μM, respectively, which were lower than that of ibuprofen. All plant extracts and pure compounds exhibited high inhibitory activity on the oxidative burst of zymosan and PMA stimulated leukocytes. Geraniin and corilagin exhibited exceptionally strong inhibition on the reactive oxygen species (ROS) activity with IC50 values lower than aspirin. The plant extracts exhibited moderate inhibition of E. coli uptake by monocytes but weak effect on PMNs. Of all the compounds, phyllanthin at 50 μg/mL exhibited the highest engulfment inhibitory activity with percentage of phagocytizing cells of 14.2 and 27.1% for PMNs and monocytes, respectively. All plants and compounds tested possessed weak effect on CD18 expression on leukocytes except for hypophyllanthin and phyllanthin which exhibited significant inhibitory effect.ConclusionThe strong inhibition of the extracts on the phagocytic activity of neutrophils was due to the presence of their major constituents especially geraniin, corilagin, phyllanthin and hypophllanthin which were able to modulate the innate response of phagocytes at different steps.

Background Gynura segetum is used traditionally to treat various ailments related to the immune system, which include cancer, inflammation, rheumatism, diabetes, hypertension, and viral infections but little studies have been carried out to validate their ethnopharmacological aspects. In this study the immunosuppressive effects of G. segetum and its constituents were investigated.MethodsIsolation of compounds from G. segetum leaves was conducted using vacuum liquid chromatography (VLC) and column chromatography (CC). Two new compounds, namely 4,5,4'-trihydroxychalcone and 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol, together with stigmasterol and β-sitosterol were isolated from G. segetum methanol extract and their structures were determined spectroscopically. The presence of gallic acid and rutin in the extract was determined quantitatively by a validated HPLC method. G. segetum methanol extract and its constituents were investigated for their effects on chemotaxis, phagocytosis, β2 integrin (CD18) expression, and reactive oxygen species (ROS) of polymorphonuclear leukocytes (PMNs), lymphocytes proliferation, cytokine release and nitric oxide (NO) production of phagocytes.ResultsAll the samples significantly inhibited all the innate immune responses tested except CD 18 expression on surface of leukocytes. Among the samples, 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol exhibited the strongest inhibitory on chemotaxis, phagocytosis, ROS and NO production. The compound exhibited exceptionally strong inhibitions on ROS and chemotaxis activities with IC50 values lower than the positive controls, aspirin and ibuprofen, respectively. 4,5,4'-Trihydroxychalcone revealed the strongest immunosuppressive activity on proliferation of lymphocytes (IC50 value of 1.52 μM) and on release of IL-1β (IC50 value of 6.69 μM). Meanwhile rutin was the most potent sample against release of TNF-α from monocytes (IC50, 16.96 μM).ConclusionThe extract showed strong immunosuppressive effects on various components of the immune system and these activities were possibly contributed mainly by 4,5,4'-trihydroxychalcone, 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol and rutin.

Curcuma species (family: Zingiberaceae) are widely utilized in traditional medicine to treat diverse immune-related disorders. There have been many scientific studies on their immunomodulating effects to support their ethnopharmacological uses. In this review, the efficacy of six Curcuma species, namely, C. longa L., C. zanthorrhiza Roxb., C. mangga Valeton & Zijp, C. aeruginosa Roxb. C. zedoaria (Christm.) Roscoe, and C. amada Roxb., and their bioactive metabolites to modulate the immune system, their mechanistic effects, and their potential to be developed into effective and safe immunomodulatory agents are highlighted. Literature search has been carried out extensively to gather significant findings on immunomodulating activities of these plants. The immunomodulatory effects of Curcuma species were critically analyzed, and future research strategies and appropriate perspectives on the plants as source of new immunomodulators were discussed. Most of the pharmacological investigations to evaluate their immunomodulatory effects were in vivo and in vitro experiments on the crude extracts of the plants. The extracts were not chemically characterized or standardized. Of all the Curcuma species investigated, the immunomodulatory effects of C. longa were the most studied. Most of the bioactive metabolites responsible for the immunomodulating activities were not determined, and mechanistic studies to understand the underlying mechanisms were scanty. There are limited clinical studies to confirm their efficacy in human. Of all the bioactive metabolites, only curcumin is undergoing extensive clinical trials based on its anti-inflammatory properties and main use as an adjuvant for the treatment of cancer. More in-depth studies to understand the underlying mechanisms using experimental in vivo animal models of immune-related disorders and elaborate bioavailability, preclinical pharmacokinetics, and toxicity studies are required before clinical trials can be pursued for development into immunomodulatory agents.

The standardized methanol extracts of Phyllanthus amarus and P. urinaria, collected from Malaysia and Indonesia, and their isolated chemical markers, phyllanthin and hypophyllanthin, were evaluated for their effects on the chemotaxis, phagocytosis and chemiluminescence of human phagocytes. All the plant extracts strongly inhibited the migration of polymorphonuclear leukocytes (PMNs) with the Malaysian P. amarus showing the strongest inhibitory activity (IC50 value, 1.1 µg/mL). There was moderate inhibition by the extracts of the bacteria engulfment by the phagocytes with the Malaysian P. amarus exhibiting the highest inhibition (50.8% of phagocytizing cells). The Malaysian P. amarus and P. urinaria showed strong reactive oxygen species (ROS) inhibitory activity, with both extracts exhibiting IC50 value of 0.7 µg/mL. Phyllanthin and hypophyllanthin exhibited relatively strong activity against PMNs chemotaxis, with IC50 values slightly lower than that of ibuprofen (1.4 µg/mL). Phyllanthin exhibited strong inhibitory activity on the oxidative burst with an IC50 value comparable to that of aspirin (1.9 µg/mL). Phyllanthin exhibited strong engulfment inhibitory activity with percentage of phagocytizing cells of 14.2 and 27.1% for neutrophils and monocytes, respectively. The strong inhibitory activity of the extracts was due to the presence of high amounts of phyllanthin and hypophyllanthin although other constituents may also contribute.

Objective: This study was conducted to evaluate the immunomodulatory effects of ethanol extract of Curcuma mangga by in vivo study.Methods: The ethanol extract of C. mangga was comprised to carbon clearance method for its immunomodulatory potential. The extract wasadministered orally at doses of 100, 200, and 400 mg/kg BW to mice for 7 days. On day 8, carbon ink was injected, and the blood was collected formeasurement of elimination of carbon. Total leukocyte count was also determined.Results: The evaluation of immunomodulatory potential of ethanol extract of C. mangga revealed a dose-dependent increase in phagocytosis ability.The phagocytic index of ethanol extract of C. mangga was more than those of negative control, indicating the immunostimulatory activity of C. mangga.It showed low stimulation on total leukocyte count.Conclusion: The results indicate that ethanol extract of C. mangga rhizomes possesses immunomodulatory activity and has therapeutic potential forthe treatment of infectious diseases.

Background and purpose: Recently, we have highlighted the immunomodulatory activity of Curcuma mangga Val. on phagocytosis ability. The current study was conducted to determine the immunomodulatory effects of the standardized extract of C. mangga rhizomes by in vitro and in vivo studies. Experimental approach: The C. mangga extract was standardized according to a guideline for herbal preparation. The extract was investigated for its immunomodulatory effects on gene expression of cytokines, cytokines and antibody production as well as delayed-type hypersensitivity (DTH) response. The gene expression of cytokines on lipopolysaccharide-induced-RAW 264.7 cells was analysed by reverse transcription-polymerase chain reaction (RT-PCR) method. The effect of the extract on DTH response was investigated by the paw edema method, meanwhile the effects of the extract on antibody and cytokine production from normal and cyclophosphamide-induced Salmonella typhimurium infected rats were determined using an enzyme-linked immunosorbent assay (ELISA). Findings/Results: The extract of C. mangga demonstrated an inhibitory effect on gene expression of interleukin-1β (IL-1β), tumor necrosis factor-α, and IL-6 as compared to lipopolysaccharide-induced cells. The extract also depicted inhibitory activity on IL-4 production as compared to the negative control. Whereas, the DTH response and production of immunoglobulin G from both groups after treatment with C. mangga extract were higher than those of negative control ( P < 0.05). Conclusion and implications: The results indicated that the C. mangga extract has immunomodulatory effects, emphasizing its potential to be developed as immunotherapeutic agent.

The present study was conducted to correlate between the phytochemical constituents in the extract of C. mangga rhizomes and its immunomodulatory effect on phagocytosis of mice leukocytes. The phytochemical screening was performed using the standard method, while qualitative analysis of curcumin in C. mangga extract was examined using Thin Layer Chromatography (TLC). The n-hexane, ethyl acetate and ethanol extracts of C. mangga were introduced to carbon clearance method for their immunomodulatory potential. The phytochemical screening on nhexane and ethanol extracts of C. mangga rhizomes revealed the presence of steroids and terpenoids. Meanwhile, glycosides, saponins and flavonoids were detected in ethyl acetate and ethanol extracts. The TLC analysis led to the identification of curcumin in all extracts. All the samples tested demonstrated the immunostimulatory effect on phagocytosis ability of mice leukocytes. Of all the extracts, n-hexane extract displayed the strongest stimulation on phagocytosis effect but there was no significantly different (P>0.05). The results suggest that the immunostimulatory activity of extract on phagocytosis ability was due to the presence of its major constituents although other constituents may also contribute.

Objective: Doxorubicin (DOX) is a drug of choice in many cancer therapies. Virgin coconut oil (VCO) is one of nutraceutical which has many biology activities. This current study was carried out to investigate the VCO activity in modulating TCD4+, and TCD8+ cells profile toward rats which induced by DOX.Methods: A total of 15 Sprague-Dawley rats were divided into three groups consisting of five rats each as follows: Group 1, receiving oral saline 10 mL Kg BW (control group); Group 2, receiving oral saline 10 mL/kg BW; and Group 3, receiving VCO 5 mL/kg BW. Group 2 and 3 were administered with DOX intramuscularly at dose 4.67 mg/kg BW at day 1 and 4 to suppressed immune functions.Results: Treatment of VCO 5 mL/kg BW succeeded in reducing a side effect of DOX based on increasing the TCD4+ and TCD8+ blood level. Conclusion:The results reveal that VCO could increase the level of TCD4+ and TCD8+ in rats which induced by DOX.