Systemic treatment with n-6 polyunsaturated fatty acids attenuates EL4 thymoma growth and metastasis through enhancing specific and non-specific anti-tumor cytolytic activities and production of TH1 cytokines

Beneficial Actions of Essential Fatty Acids in Streptozotocin-Induced Type 1 Diabetes Mellitus

The essential fatty acids (EFA), n3 alpha-linolenic acid (ALA), and n6 linoleic acid (LA) are of benefit in diabetes mellitus, but their mechanisms of action are unknown. We, therefore, examined the effects of EFAs on the metabolism, gut microbiota, and inflammatory and retinal histopathology indices in streptozotocin (STZ)-induced type 1 diabetes mellitus (T1DM) animals, and we assessed the levels of vitreal lipoxin A4 (LXA4)-derived from LA-in subjects with diabetic retinopathy (DR). STZ-induced T1DM rats received LA or ALA 100 μg/day intraperitoneally on alternate days for 21 days, and their blood glucose; lipid profile; plasma, hepatic, and retinal fatty acid profiles (by gas chromatography); retinal histology; activities of hepatic and retinal desaturases; and inflammatory markers (by qRT-PCR) were evaluated. Gut microbiota composition was assayed by 16S rDNA sequencing technology of the fecal samples, and their short-chain fatty acids and bile acids were assayed by gas chromatography, liquid chromatography coupled with tandem mass spectrometry, respectively. The human vitreal fatty acid profiles of subjects with proliferative DR and LXA4 levels were measured. LA and ALA significantly improved the plasma glucose and lipid levels; increased the abundance of Ruminococcaceae (the ALA-treated group), Alloprevotella, Prevotellaceae_Ga6A1_group, Ruminococcaceae_UCG_010, and Ruminococcus_1 (the LA-treated group) bacteria; enhanced acetate and butyrate levels; and augmented fecal and hepatic concentrations of cholic acid, chenodeoxycholic acid, and tauro ursodeoxycholic acid in ALA- and LA-treated animals. Significant STZ-induced decreases in plasma LA, gamma-linolenic acid, arachidonic acid, and ALA levels reverted to near normal, following LA and ALA treatments. Significant changes in the expression of desaturases; COX-2, 5-LOX, and 12-LOX enzymes; and cytokines in T1DM were reverted to near normal by EFAs. DR subjects also had low retinal LXA4 levels. The results of the present study show that ALA and LA are of significant benefit in reversing metabolism, gut microbiota, and inflammatory and retinal index changes seen in T1DM, suggesting that EFAs are of benefit in diabetes mellitus.

Perilla Fruit Oil-Fortified Soybean Milk Intake Alters Levels of Serum Triglycerides and Antioxidant Status, and Influences Phagocytotic Activity among Healthy Subjects: A Randomized Placebo-Controlled Trial

This study aimed to develop perilla fruit oil (PFO)-fortified soybean milk (PFO-SM), identify its sensory acceptability, and evaluate its health outcomes. Our PFO-SM product was pasteurized, analyzed for its nutritional value, and had its acceptability assessed by an experienced and trained descriptive panel (n = 100) based on a relevant set of sensory attributes. A randomized clinical trial was conducted involving healthy subjects who were assigned to consume deionized water (DI), SM, PFO-SM, or black sesame-soybean milk (BS-SM) (n = 48 each, 180 mL/serving) daily for 30 d. Accordingly, health indices and analyzed blood biomarkers were recorded. Consequently, 1% PFO-SM (1.26 mg ALA rich) was generally associated with very high scores for overall acceptance, color, flavor, odor, taste, texture, and sweetness. We observed that PFO-SM lowered levels of serum triglycerides and erythrocyte reactive oxygen species, but increased phagocytosis and serum antioxidant activity (p < 0.05) when compared to SM and BS-SM. These findings indicate that PFO supplementation in soybean milk could enhance radical-scavenging and phagocytotic abilities in the blood of healthy persons. In this regard, it was determined to be more efficient than black sesame supplementation. We are now better positioned to recommend the consumption of PFO-SM drink for the reduction of many chronic diseases. Randomized clinical trial registration (Reference number 41389) by IRSCTN Registry.

Combination therapy with interferon beta-1a and sesame oil in multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system. Several effector mechanisms are involved in the immunopathology of MS and a variety of medications such as beta interferons are applied to treat the disease. This study was conducted to evaluate the anti-inflammatory and immunomodulatory effects of sesame oil in combination with interferon beta-1a in MS treatment.

METHODS

Ninety-three MS patients were enrolled in the study. The patients were randomly divided into two groups. The control group (n = 39) received 30 μg/week of interferon beta-1a intra-muscularly. The sesame oil-treated group (n = 54) received interferon beta-1a the same as the control group with the addition of 0.5 ml/kg/day of oral sesame oil for 6 months.

RESULTS

After the 6-month study period, the interleukin (IL)-10 concentration in the sesame oil-treated group was significantly greater than that of the control group (p = 0.04). The concentrations of interferon-γ (IFN-γ), nitric oxide (NO), and tumor necrosis factor-α (TNF-α) in the sesame oil group after treatment were significantly less than those of the control group (p = 0.029, p = 0.0001, and p = 0.01, respectively). Lymphocyte proliferation in the sesame oil-treated group was significantly lower at the end of the study than at the beginning (p = 0.001).

CONCLUSION

Sesame oil, through a decrease in IFN-γ secretion and anti-inflammatory and anti-oxidant activities, may have beneficial effects for MS patients.

Tumor Challenges in Immunotoxicity Testing

Syngeneic murine tumor models have been widely used by researchers to assess changes in tumor susceptibility associated with exposure to toxicants. Two common tumor models used to define host resistance against transplanted tumors in vivo are EL4 mouse lymphoma cells (established from a lymphoma induced in a C57BL/6 mouse by 9,10-dimethyl-1,2-benzanthracene) and B16F10 mouse melanoma cells (derived through variant selection from a B16 melanoma arising spontaneously in C57BL/6 mice). While C57BL/6 mice are commonly used as the syngeneic host for these tumor models, other mouse strains such as B₆C₃F₁ (C57BL/6 × C3H) can also be used. Tumor challenge of the host can be done by subcutaneous (sc) or intravenous (iv) injection, depending upon whether the effects are to be examined on local tumor development or experimental/artificial metastasis. Materials and methodologies for injection of both tumor cell models are described in detail in the subsequent sections.

Nuclear Factor of Activated T Cells-dependent Down-regulation of the Transcription Factor Glioma-associated Protein 1 (GLI1) Underlies the Growth Inhibitory Properties of Arachidonic Acid

Numerous reports have demonstrated a tumor inhibitory effect of polyunsaturated fatty acids (PUFAs). However, the molecular mechanisms modulating this phenomenon are in part poorly understood. Here, we provide evidence of a novel antitumoral mechanism of the PUFA arachidonic acid (AA). In vivo and in vitro experiments showed that AA treatment decreased tumor growth and metastasis and increased apoptosis. Molecular analysis of this effect showed significantly reduced expression of a subset of antiapoptotic proteins, including BCL2, BFL1/A1, and 4-1BB, in AA-treated cells. We demonstrated that down-regulation of the transcription factor glioma-associated protein 1 (GLI1) in AA-treated cells is the underlying mechanism controlling BCL2, BFL1/A1, and 4-1BB expression. Using luciferase reporters, chromatin immunoprecipitation, and expression studies, we found that GLI1 binds to the promoter of these antiapoptotic molecules and regulates their expression and promoter activity. We provide evidence that AA-induced apoptosis and down-regulation of antiapoptotic genes can be inhibited by overexpressing GLI1 in AA-sensitive cells. Conversely, inhibition of GLI1 mimics AA treatments, leading to decreased tumor growth, cell viability, and expression of antiapoptotic molecules. Further characterization showed that AA represses GLI1 expression by stimulating nuclear translocation of NFATc1, which then binds the GLI1 promoter and represses its transcription. AA was shown to increase reactive oxygen species. Treatment with antioxidants impaired the AA-induced apoptosis and down-regulation of GLI1 and NFATc1 activation, indicating that NFATc1 activation and GLI1 repression require the generation of reactive oxygen species. Collectively, these results define a novel mechanism underlying AA antitumoral functions that may serve as a foundation for future PUFA-based therapeutic approaches.

Prenatal exposure to cigarette smoke alters later-life antitumor cytotoxic T-lymphocyte (CTL) activity via possible changes in T-regulatory cells

Epidemiological studies suggest that maternal smoking increases the incidence in the progeny of certain childhood cancers. Our previous study in mice demonstrated the feasibility of such an association by demonstrating that prenatal exposure to cigarette smoke (CS) elevated the incidence of transplanted tumors and reduced cytotoxic T-lymphocyte (CTL) activity in juvenile male offspring. The current study extends these findings by investigating the relationship between CS-induced CTL suppression and effects on regulators of effector T-cell activity, such as T-regulatory (Treg; CD4+ CD25+ Foxp3+) cells and transforming growth factor (TGF)-β. Results here demonstrate that in utero exposure to CS, at a maternal particle concentration of 15 mg/m3 (4 h/d, 5 d/wk), significantly reduced ex vivo CTL activity of whole splenocytes (and isolated CD8+ cells) against tumor cells both before and after injection of prenatally exposed mice with EL4 lymphoma cells. In contrast, prenatal CS exposure significantly increased levels of thymic Treg cells in a time-dependent manner following tumor cell injection. In vitro production of TGF-β by splenocytes recovered from prenatally exposed, tumor-bearing mice was also altered. Neither prenatal CS exposure nor subsequent administration of EL4 cells exerted any marked effects on lymphoid organ weights, cellularity, or histologic profiles. Given that Treg cells and TGF-β suppress effector T-cell activities, these findings suggest possible immune mechanisms by which early exposure to CS reduces CTL tumoricidal activity during tumor cell development. Data suggest that children of smoking mothers may be less able to mount an appropriate adaptive immune response to tumors, thus increasing their risk for some cancers later in life.

TNF-α-decreased thrombomodulin expression in monocytes is inhibited by propofol through regulation of tristetraprolin and human antigen R activities

Thrombomodulin (TM) is expressed on the surface of monocytes and is a key regulator of actual immune capacity. Propofol is an anesthetic agent that exerts anti-inflammatory effects. The objective of this study was to determine whether propofol could modulate TM in TNF-α-stimulated monocytes. THP-1 cells and male New Zealand rabbits were used in this study. The results showed that TNF-α decreases the TM expression by mediating posttranscriptional modification, and this inhibition may be repressed by treatment with propofol. Immunofluorescence, immunoprecipitation, and pull-down assays were used to demonstrate that Rac1-dependent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, Cdc42, and p38 mitogen-activated protein kinase activation, as well as tristetraprolin (TTP) expression, all contributed to the downregulation of TM in TNF-α-treated cells. Propofol reversed the effects of TNF-α on TM downregulation. Propofol mediated the expression of intracellular TTP and the distribution of cytosolic human antigen R (HuR) and changed their interactions with the 3'-untranslated region of TM mRNA regulating by Cdc42 and Rac1. In addition, the animal study showed that propofol regulates TM, TTP, and HuR expression on monocytes in TNF-α-treated rabbits. In conclusion, the inhibition of TM expression in TNF-α-treated monocytes was mediated by the activation of NADPH oxidase and the expression of TTP. Propofol may inhibit the downregulation of TM by mediating NADPH oxidase and TTP inactivation and through the activation of HuR in vitro and in vivo. Utilizing TTP and HuR to control TM expression may be a promising approach for controlling systemic inflammation, and propofol may possess potential implications for the clinical immunity of monocytes after anesthesia or surgery.

The mechanism of sesame oil in ameliorating experimental autoimmune encephalomyelitis in C57BL/6 mice

Experimental autoimmune encephalomyelitis (EAE) is a Th1 cell-mediated autoimmune disease of the CNS that serves as an animal model for multiple sclerosis (MS). The study investigated the effectiveness of treatment with sesame oil on the development of EAE. EAE was induced in 8 week old C57BL/6 mice with an emulsion of MOG35-55. Therapy with sesame oil (4 mL/kg/day as oral gavage) was started on day 3 before the immunization. IFN-gamma and IL-10 production from cultured spleen supernatants were determined by the ELISA method. The results showed that daily oral gavage of sesame oil significantly reduced the clinical symptoms of EAE in C57BL/6 mice. In addition, sesame oil-treated mice displayed a significantly delayed disease onset. Mononuclear cells isolated from spleen of sesame oil-treated mice showed a significant decrease in the production of IFN-gamma compared with control mice (p = 0.001). IL-10 production was also enhanced in splenic mononuclear cells in sesame oil-treated mice. The ratio of IFN-gamma to IL-10 in sesame oil-treated EAE mice was significantly less than in non-treated EAE mice (p = 0.01). This report indicates that sesame oil therapy protected mice from developing EAE by reducing IFN-gamma secretion. Thus, sesame oil treatment may be effective in MS patients by immunomodulating the Th1 immune response.

Tumor challenges in immunotoxicity testing

Syngeneic murine tumor models have been widely used by researchers to assess changes in tumor susceptibility associated with exposure to toxicants. Two common tumor models used to define host resistance against transplanted tumors in vivo are EL4 mouse lymphoma cells (established from a lymphoma induced in a C57BL/6 mouse by 9,10-dimethyl-1,2-benzanthracene) and B16F10 mouse melanoma cells (derived through variant selection from a B16 melanoma arising spontaneously in C57BL/6 mice). While C57BL/6 mice are commonly used as the syngeneic host for these tumor models, other mouse strains such as B(6)C(3)F(1) (C57BL/6 x C3H) can also be used. Tumor challenge of the host can be done by subcutaneous (sc) or intravenous (iv) injection, depending upon whether the effects are to be examined on local tumor development or experimental/artificial metastasis. Materials and methodologies for injection of both tumor cell models are described in detail in the subsequent sections.

Recent trends in the advanced analysis of bioactive fatty acids

The consumption of dietary fats have been long associated to chronic diseases such as obesity, diabetes, cancer, arthritis, asthma, and cardiovascular disease; although some controversy still exists in the role of dietary fats in human health, certain fats have demonstrated their positive effect in the modulation of abnormal fatty acid and eicosanoid metabolism, both of them associated to chronic diseases. Among the different fats, some fatty acids can be used as functional ingredients such as alpha-linolenic acid (ALA), arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), gamma-linolenic acid (GLA), stearidonic acid (STA) and conjugated linoleic acid (CLA), among others. The present review is focused on recent developments in FAs analysis, covering sample preparation methods such as extraction, fractionation and derivatization as well as new advances in chromatographic methods such as GC and HPLC. Special attention is paid to trans fatty acids due its increasing interest for the food industry.

Fatty acids isolated from royal jelly modulate dendritic cell-mediated immune response in vitro

Royal jelly (RJ), especially its protein components, has been shown to possess immunomodulatory activity. However, almost nothing is known about the influence of RJ fatty acids on the immune system. In this work we studied the effect of 10-hydroxy-2-decanoic acid (10-HDA) and 3,10-dihydroxy-decanoic acid (3,10-DDA), isolated from RJ, on the immune response using a model of rat dendritic cell (DC)-T-cell cocultures. Both fatty acids, at higher concentrations, inhibited the proliferation of allogeneic T cells. The effect of 10-HDA was stronger and was followed by a decrease in interleukin-2 (IL-2) production and down-regulation of IL-2 receptor expression. Spleen DC, cultivated with 10 microg/ml of fatty acids down-regulated the expression of CD86 and the production of IL-12, but up-regulated the production of IL-10. In contrast, DC, pretreated with 100 microg/ml of 3,10-DDA, up-regulated the expression of CD86 and augmented the proliferation of allogeneic T cells. The highest dose (200 microg/ml) of both fatty acids which was non-apoptotic for both T cells and DC, down-regulated the expression of MHC class II and CD86, decreased the production of IL-12 and made these DC less allostimulatory. The immunosuppressive activity of 3,10-DDA was also confirmed in vivo, using a model of Keyhole lymphet hemocyanine immunization of rats. In conclusion, our results showed the immunomodulatory activity of RJ fatty acids and suggest that DC are a significant target of their action.

Effect of sesame oil on the inhibition of experimental autoimmune encephalomyelitis in C57BL/6 mice

Sesame oil was evaluated in the treatment of in C57BL/6 mice. It has profound anti-inflammatory activity and been traditionally used to treat inflammatory disorders. EAE was induced by immunization of 6-8 week old mice with MOG(35-55) with complete Freunds adjuvant. Therapy with sesame oil was started on day 3 before the immunization. Total Antioxidant Capacity (TAC) was assessed by Ferric Reducing-antioxidant Power (FRAP) method. Nitric Oxide (NO) production was also estimated by Griess reaction. For histological analysis, mice brain was harvested and sections were stained with Hematoxylin-Eosin. After daily intraperitoneal dosage the sesame oil significantly reduced the clinical symptoms in C57BL/6 mice with EAE. Also, treated mice displayed a significantly delayed disease onset compared with control mice. Sesame oil significantly increased TAC, but it's effect on serum nitrite production was not significant. Typical brain leukocyte infiltration was observed in control mice compared with treated mice. Present results suggest for the first time that sesame oil therapy may be effective in the prevention of symptomatic EAE. This resistance to encephalomyelitis may be associated with inhibition of oxidative stress.