Genotoxicity testing of low molecular weight fucoidan from brown seaweeds

Fucoidan extracts from brown seaweed have anticoagulant, antithrombotic, and antiviral activities. Low molecular weight fucoidan (LMF) obtained by acid hydrolysis of high molecular weight fucoidan showed more favorable bioactivity. Despite extensive work on LMF bioactivities, detailed studies on the genotoxicity of LMF have not been conducted. As part of a safety evaluation, the potential genotoxicity of LMF was evaluated using a standard battery of tests (bacterial reverse mutation assay, chromosomal aberrations assay, and mouse micronucleus assay). The LMF was determined not to be genotoxic under the conditions of the reverse mutation assay, chromosomal aberrations assay, or mouse micronucleus assay. In a reverse mutation assay using four Salmonella typhimurium strains and Escherichia coli, LMF did not increase the number of revertant colonies in any tester strain regardless of metabolic activation by S9 mix, and did not cause chromosomal aberration in short tests with the S9 mix or in the continuous (24 h) test. A bone marrow micronucleus test in ICR mice dosed by oral gavage at doses up to 2000 mg/kg body weight/day showed no significant or dose-dependent increases in the frequency of micronucleated polychromatic erythrocytes. Use of LMF is presently expected to be safe, as anticipated intake is small compared to doses administered in the genotoxicity assays and may prove to be a useful bioactive agent after further toxicity research.     

Genotoxicity testing of sodium formononetin-3′-sulphonate (Sul-F) by assessing bacterial reverse mutation,chromosomal aberrations and micronucleus tests

As part of a safety evaluation, we evaluated the potential genotoxicity of sodium formononetin-3′-sulphonate (Sul-F) using bacterial reverse mutation assay, chromosomal aberrations detection, and mouse micronucleus test. In bacterial reverse mutation assay using five strains of Salmonella typhimurium (TA97, TA98, TA100, TA102 and TA1535), Sul-F (250, 500, 1000, 2000, 4000 μg/plate) did not increase the number of revertant colonies in any tester strain with or without S9 mix. In a chromosomal assay using Chinese hamster lung fibroblast (CHL) cells, there were no increases in either kind of aberration at any dose of Sul-F (400, 800, and 1600 μg/mL) treatment groups with or without S9 metabolic activation. In an in vivo bone marrow micronucleus test in ICR mice, Sul-F at up to 2000 mg/kg (intravenous injection) showed no significant increases in the incidence of micronucleated polychromatic erythrocytes, and the proportion of immature erythrocytes to total erythrocytes. The results demonstrated that Sul-F does not show mutagenic or genotoxic potential under these test conditions.     

Evaluation of genotoxicity of multi-walled carbon nanotubes in a battery of in vitro and in vivo assays

The genotoxic potential of two products of multi-walled carbon nanotubes (coded as N-MWCNTs, diameter of 44 nm/BET surface area of 69 m²/g and MWNT-7, diameter of 70 nm/BET surface area of 23 m²/g) was evaluated using a battery of genotoxicity assays, comprising a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and a mammalian erythrocytes micronucleus test. Neither type exerted mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, and TA1537, or in Escherichia coli WP2uvrA, in the absence or presence of metabolic activation. The products of MWCNTs did not increase the number of structural chromosomal aberrations either, regardless of metabolic activation, though they increased the number of numerical chromosomal aberrations, one slightly and the other distinctly, in the absence of metabolic activation. In ICR mice, the two products did not affect the proportion of immature erythrocytes, the total proportion of erythrocytes, or the number of micronuclei in immature erythrocytes.     

Genotoxicity studies on the root extract of Polygala tenuifolia Willdenow

The root of Polygala tenuifolia Willdenow has been used for the treatment against insomnia, amnesia, depression, palpitations with anxiety, and memory improvement. However, there is no sufficient background information on toxicological evaluation of the root to given an assurance of safety for developing dietary supplements and functional foods. As part of a safety evaluation, the potential genotoxicity of the root extract of P. tenuifolia was evaluated using a standard battery of tests (bacterial reverse mutation assay, chromosomal aberrations assay, and mouse micronucleus assay). In a reverse mutation assay using four Salmonella typhimurium strains and Escherichia coli, the extract did not increase the number of revertant colonies in any tester strain with or without metabolic activation by S9 mix, and did not cause chromosomal aberration in short-period test with the S9 mix or in the continuous (24 h) test. A bone marrow micronucleus test in ICR mice dosed by oral gavage at doses up to 2000 mg/kg/day showed no significant or dose dependent increase in the frequency of micronucleated polychromatic erythrocytes (PCE). These results indicate that ingesting the rot extract P. tenuifolia is not genotoxic at the proper dose.     

Safety studies of LP20 powder produced from heat-killed Lactobacillus plantarum L-137

The safety of LP20 and its prototype, a powder, with potential use in food, produced from a mixture of dextrin and heat-killed Lactobacillus plantarum L-137, was assessed in an acute study in mice, and in an in vitro bacterial reverse mutation assay, an in vitro chromosome aberration assay, and an in vivo mouse micronucleus assay. LP20 prototype was not acutely toxic when administered to male and female Slc:ICR mice by single gavage at 2000 mg/kg bw. Dosing was not associated with mortality, clinical signs, changes in bodyweight, or macroscopic abnormalities. The LD₅₀ in mice was greater than 2000 mg/kg bw. There was no evidence of genotoxicity of LP20 in the Ames assay (0–5000 μg/plate) or in the in vitro chromosome aberration assay with Chinese hamster lung fibroblasts (0–5000 μg/mL). Administration of two consecutive daily doses of 500, 1000, or 2000 mg/kg bw by gavage to male Crlj:CD-1 mice was not associated with an increased incidence of micronuclei and did not alter the ratio of polychromatic to normochromatic erythrocytes. These studies show that LP20 powder is not acutely toxic and is without genotoxic activity both in vitro and in vivo.     

Evaluation of the genotoxic potential and acute oral toxicity of standardized extract of Andrographis paniculata (KalmCold™)

Andrographis paniculata is used in the traditional medicine for cold and influenza remedy. The main endeavor in this study was to assess the genotoxicity of the standardized extract of A. paniculata (KalmCold™) through three different in vitro tests: Ames, chromosome aberration (CA), and micronucleus (MN). Ames test was performed at 5000 μg/ml, 1581 μg/ml, 500 μg/ml, 158 μg/ml, 50 μg/ml, 16 μg/ml, while the clastogenicity tests were performed at 80 μg/ml, 26.6 μg/ml, 8.8 μg/ml for short-term treatment without S9; 345 μg/ml, 115 μg/ml, 38.3 μg/ml for short-term treatment with S9; and 46 μg/ml, 15.3 μg/ml, 5.1 μg/ml for long-term without S9 using DMSO as a vehicle control. Results of Ames test confirmed that KalmCold™ did not induce mutations both in the presence and absence of S9 in Salmonella typhimurium mutant strains TA98 and TAMix. In CA and MN, KalmCold™ did not induce clastogenicity in CHO-K1 cells in vitro. Based on our results, it is evident that KalmCold™ is genotoxically safe.     

Safety evaluation of proanthocyanidin polymer-rich fraction obtained from stem bark of Stryphnodendron adstringens (BARBATIMÃO) for use as a pharmacological agent

The widespread use of medicinal plants among the Brazilian population warrants an assessment of the potential risks associated with their intake. Stryphnodendron adstringens (barbatimão) is one of the most frequently used medicinal plants in Brazil, and the risks associated with its use have yet to be investigated. This study evaluated the genotoxic safety of the use of the proanthocyanidin polymer-rich fraction (F2) of stem bark of S. adstringens. The micronucleus test with 750, 1500, and 2250 mg kg⁻¹ of F2 administered in Mus musculus (Swiss) outbred mice, showed respectively, 5.0 ± 0.8 (Mean ± S.D.), 9.1 ± 1.7, and 10.6 ± 1.9 micronucleated polychromatic erythrocytes (MNPCE). A positive control with cyclophosphamide resulted in 21.0 ± 3.8 MNPCE. Antimutagenicity was also evaluated, by adding 750 mg kg⁻¹ to cyclophosphamide; the result of 8.7 ± 1.4 showed a protective cytotoxic effect. For the Artemia salina test, 10, 100, and 1000 mg L⁻¹ of F2 showed, respectively, 8.7 ± 0.6, 7.7 ± 0.6, and 5.7 ± 1.2 survival, i.e., F2 did not inhibit 50% of the population when compared to the control (9.7 ± 0.6). These results indicated that F2 obtained from stem bark of S. adstringens has no genotoxic activity.     

Genotoxicity studies on licorice flavonoid oil (LFO)

Licorice flavonoid oil (LFO) is a new functional food ingredient. In this study, the genotoxicity of LFO was investigated using a test battery of three different methods. In a reverse mutation assay using four Salmonella typhimurium strains and Escherichia coli, LFO did not increase the number of revertant colonies in any tester strain with or without metabolic activation by rat liver S9 mix. In a chromosomal aberration test using Chinese hamster lung (CHL/IU) cells, LFO did not induce any chromosomal aberrations either in the short period test without rat liver S9 mix or in the continuous treatment (24 h or 48 h) test. However, in the short-period test with rat liver S9 mix, LFO induced structural chromosomal aberrations at concentrations higher than 0.6 mg/mL. A bone marrow micronucleus test using male F344 rats was initially conducted. The animals were dosed by oral gavage at doses up to 5000 mg/kg/day. No significant or dose-dependent increases in the frequency of micronucleated polychromatic erythrocytes (MNPCE) were observed and the high dose suppressed the ratio of polychromatic erythrocytes (PCE) to total erythrocytes. Subsequently, a liver and peripheral blood micronucleus test using male F344 rats was conducted. No micronuclei induction either in hepatocytes or PCE was observed even at the highest dose of 5000 mg/kg/day. From the findings obtained from the genotoxicity assays performed in this study and the published pharmacokinetic studies of LFO, it appears unlikely that dietary consumption of LFO will present any genotoxic hazard to humans.     

Literature review on the safety of Toyocerin,a non-toxigenic and non-pathogenic Bacillus cereus var. toyoi preparation

Bacillus cereus var. toyoi is a naturally occurring, non-toxigenic and non-pathogenic strain of B. cereus. Safety studies were conducted on a B. toyoi preparation (Toyocerin^®), including but not limited to enterotoxicity, eye irritation, genotoxicity, acute, subchronic and chronic toxicity studies and human clinical trials. In rabbits, Toyocerin^® did not exhibit enterotoxicity and was only slightly irritating to the eyes. It was non-mutagenic in an Ames assay at up to 10,000 μg/plate and did not exhibit clastogenic activity in a chromosomal aberration test at up to 450 mg/ml. It was non-toxic in acute and repeated-dose (30 and 60 days and 1 year) toxicity studies in rats and mice at up to 3 × 10¹¹ spores/kg bw/day. In an eight-day human clinical trial, Toyocerin^® did not cause any adverse effects in healthy male and female subjects at 1 × 10⁹ and 1 × 10¹⁰ spores/kg bw/day. In feeding trials, Toyocerin^® did not cause any adverse effects in rabbits, pigs, chickens, turkeys and cattle at doses ranging from 8.5 × 10⁷ to 4 × 10⁹ spores/kg bw/day for durations of 2 weeks to 18 months. Taken together, these studies demonstrate that Toyocerin^® is safe at the doses tested.     

Therapeutic efficacies of Coriandrum sativum aqueous extract against metronidazole-induced genotoxicity in Channa punctatus peripheral erythrocytes

Metronidazole (MTZ), a nitroimidazole drug, is primarily used as an anti-protozoan or an anti-bacterial agent in humans, although its genotoxic and carcinogenic effects have been widely reported, particularly in aquatic organisms. MTZ may induce DNA damages through single-strand breaks, modification of bases, DNA–DNA and DNA–protein cross-links, ultimately leading to apoptosis or necrosis. Here, we have assessed the genotoxicity of MTZ in the peripheral erythrocytes of Channa punctatus, using micronucleation (MN) and binucleation (BN) as genotoxicity markers. The therapeutic potential of aqueous extract of Coriandrum sativum against MTZ-induced genotoxicity has also been examined. The results show significant (P < 0.05) increase in both MN and BN formation due to MTZ treatment. Such aberrations were higher in smaller fish samples for a particular dosage of MTZ, as established by correlation analysis between fish body weight and MN/BN count at P < 0.05. However, such degenerative damages were found to be alleviated by a great extent due to treatment with C. sativum leaf extract. Hence, we establish that MTZ can produce considerable degrees of micronucleus and binucleus formation in peripheral erythrocytes of C. punctatus, and such deleterious effect of MTZ treatment can be mitigated by aqueous extract of C. sativum leaves.     

Genotoxic evaluation of pirfenidone using erythrocyte rodent micronucleus assay

Pirfenidone is a non-steroidal antifibrotic compound that has been proposed in clinical protocols and experimental studies as a pharmacological treatment for fibroproliferative diseases. The objective of this study was to determine the genotoxicity or cytotoxicity of three doses of pirfenidone using the micronuclei test in peripheral blood erythrocytes of rodent models. Pirfenidone was administered orally to Balb-C mice for 3 days, and also was administered topically to hairless Sprague Dawley rats during the final stage of gestation. Mice were sampled every 24 h over the course of 6 days; pregnant rats were sampled every 24 h during the last 6 days of gestation, and pups were sampled at birth. Blood smears were analyzed and the frequencies of micronucleated erythrocytes (MNEs), micronucleated polychromatic erythrocytes (MNPCEs), and the proportion of polychromatic erythrocytes (PCEs), were recorded in samples from mice, pregnant rats and rat neonates. Increases in MN frequencies (p < 0.03) were noted only in the positive control groups. No genotoxic effects or decreased PCE values were observed neither in newborn rats transplacentally exposed to pirfenidone, or in two adult rodent models when pirfenidone was administered orally or topically.     

Genotoxicity studies on HM10760A,recombinant human erythropoietin conjugated to globin fragment

HM10760A is a recombinant human erythropoietin chemically conjugated to the N-terminus of human immunoglobulin Fc fragment through a polyethylene glycol linker. HM10760A was shown to have a relatively long half-life, compared with unconjugated recombinant erythropoietin. In this study, the genotoxicity of HM10760A was investigated by using a test battery of three different methods. In the Ames assay, five strains (TA100, TA1535, TA98, TA1537, and Escherichia coli WP2 uvrA) were tested at six concentrations of 3.13, 6.25, 12.5, 25, 50, and 100?μg/plate. HM10760A did not increase the number of revertant colonies in any tester strains with and without metabolic activation by rat-liver S9 mix. Subsequently, in vitro chromosomal aberration test, using Chinese hamster lung cells, were conducted at the concentrations of 25, 50, and 100?μg/mL. HM10760A did not induce chromosomal aberrations either in the short-period (6 hours) test with or without rat-liver S9 mix or in the continuous-treatment (24 hours) test. In the in vivo bone marrow micronucleus assay using the male ICR (imprinting control region) mouse, HM10760A was subcutaneously administered twice at 24-hour intervals at doses of 0, 150, 300, and 600?μg/kg. HM10760A produced a slight, but statistically significant, increase in the frequency of micronucleated polychromatic erythrocytes at 600?μg/kg. However, no biological significance was assumed, because this value was within the historical control range. From these findings obtained from the genotoxicity assays performed in this study, it appears unlikely that HM10760A acts as a genotoxic agent in vitro and in vivo.     

Chemical investigation of different crude extracts from Teucrium ramosissimum leaves. Correlation with their antigenotoxic and antioxidant properties

The effect of extracts obtained from Teucrium ramosissimum leaves on genotoxicity and SOS response induced by aflatoxin B₁ (0.5 μg/assay) as well as nitrofurantoin (5 μg/assay) was investigated in a bacterial assay system, i.e., the SOS chromotest with Escherichia coli PQ37. The T. ramosissimum tested extracts exhibited no genotoxicity either with or without the external S9 activation mixture. However, all the extracts, particularly the total oligomers flavonoids (TOF) extract significantly decreased the genotoxicity induced by aflatoxin B₁ and nitrofurantoin. Antioxidant capacity of the tested extracts was evaluated using the enzymatic (xanthine/xanthine oxidase assay) (X/XOD) and the non-enzymatic (NBT/Riboflavine assay) systems. TOF extract was the most effective one in inhibiting both xanthine oxidase activity and NBT reduction. Our findings emphasize the potential of T. ramosissimum to prevent mutations and also its antioxidant effect.     

Non-coplanar 2,2′,3,3′,4,4′,5,5′,6,6′-decachlorobiphenyl (PCB 209) did not induce cytochrome P450 enzyme activities in primary cultured rat hepatocytes,was not genotoxic,and did not exhibit endocrine-modulating activities

2,2′,3,3′,4,4′,5,5′,6,6′-Decachlorobiphenyl (PCB 209) is a fully chlorinated, non-coplanar biphenyl. To demonstrate that PCB 209 is not likely to exhibit human health hazards common to coplanar PCBs it was tested for cytochrome P450 (P450) enzyme induction potentials, genetic toxicity, and endocrine-modulating activity. PCB 209 (dose from 0.005 to 5000 ng/mL) did not significantly induce P450 CYP1A, 2A, 2B, 3A, or 4A enzyme activities in primary cultured rat hepatocytes. In contrast, Aroclor 1260, a PCB mixture that contains approximately 60% chlorine by weight, showed significant induction of P450 CYP1A, 2A, 2B, and 3A within the same dose range. PCB 209 (dose from 100 to 5000 μg/plate) was negative in the bacterial mutagenicity (Ames) test in Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537 or in Eschericia coli strain WP2uvrA. PCB 209 (dose from 25 to 150 μg/mL) was also negative for forward mutations at the thymidine kinase (TK^+/−) locus of L5178Y mouse lymphoma cells. The Ames and the mouse lymphoma assays were both conducted in the absence and presence of rat liver S9 fraction. PCB 209 (dose from 500 to 2000 mg/kg by single dose oral gavage) did not induce an increase in the frequency of micronuclei in polychromatic erythrocytes in mouse bone marrow in vivo. PCB 209 did not induce estrogenic effects when administered by gavage to ovariectomized adult female rats at 500 and 1000 mg/kg for 4 days, nor did it produce alterations consistent with endocrine-modulating activity in adult intact male rats when administered by gavage at 500 and 1000 mg/kg for 15 consecutive days.     

Safety evaluation of steroidal saponin DT-13 isolated from the tuber of Liriope muscari (Decne.) Baily

Steroidal saponin DT-13 (25 (R, S)-ruscogenin-1-O-[β-d-glucopyranosyl - (1 → 2)] [β-d-xylopyranosyl-(1 → 3)]-β-d-fucopyranoside) is the main active component of the tube of Liriope muscari (Decne.) Baily and has been studied as a candidate drug for cancer metastasis. The objective of this study was to evaluate the safety of DT-13 systematically by genotoxicity and acute oral toxicity and subchronic 90-day oral gavage toxicity. Results of Ames test confirmed that DT-13 did not induce mutations in histidine auxotrophs Salmonella typhimurium (TA 97, TA 98, TA 100 and TA 102) both in the presence and absence of metabolic activation system at the doses of 0.05-500 μg/plate. Meanwhile, DT-13 did not induce clastogenicity at doses of 1250, 2500 and 5000 mg/kg in mouse micronucleus test. And the single oral dose of DT-13 at 5000 mg/kg did not produce mortality or significant changes in the general behavior and gross appearance of the internal organs of mice. In subchronic toxicity study, DT-13 was administrated to Sprague-Dawley rats via oral gavage at doses of 10, 60 and 360 mg/kg for 90 days. Necropsy, hematological and biochemical analysis, and histopathological examination did not reveal any remarkable and treatment related changes. In conclusion, DT-13 is of low toxicity at the tested doses.     

Genotoxic evaluation of titanium dioxide nanoparticles in vivo and in vitro

With the extensive application of titanium dioxide (TiO₂) nanoparticles (NPs) in food industry, there is a rising debate concerning the possible risk associated with exposure to TiO₂ NPs. The purpose of this study is to evaluate the genotoxicity of TiO₂ NPs using in vivo and in vitro test systems. In vivo study, the adult male Sprague-Dawley rats were exposed to anatase TiO₂ NPs (75 ± 15 nm) through intragastric administration at 0, 10, 50 and 200 mg/kg body weight every day for 30 days. The γ-H₂AX assay showed TiO₂ NPs could induce DNA double strand breaks in bone marrow cells after oral administration. However, the micronucleus test revealed that the oral-exposed TiO₂ NPs did not cause damage to chromosomes or mitotic apparatus observably in rat bone marrow cells. In vitro study, Chinese hamster lung fibroblasts (V79 cells) were exposed to TiO₂ NPs at the dose of 0, 5, 10, 20, 50 and 100 μg/mL. Significant decreases in cell viability were detected in all the treated groups after 24 h and 48 h exposure. Significant DNA damage was only observed at the concentration of 100 μg/mL after 24 h treatment using the comet assay. The obvious gene mutation was observed at the concentration of 20 and 100 μg/mL after 2 h treatment using hypoxanthine-guanine phosphoribosyl transferase (HPRT) gene mutation assay. This study presented a comprehensive genotoxic evaluation of TiO₂ NPs, and TiO₂ NPs were shown to be genotoxic both in vivo and in vitro tests. The gene mutation and DNA strand breaks seem to be more sensitive genetic endpoints for the detection of TiO₂ NPs induced genotoxic effects.     

Lack of cytotoxic and genotoxic effects of Minthostachys verticillata essential oil: Studies in vitro and in vivo

Minthostachys verticillata (peperina) is an aromatic and medicinal plant with several uses and ethnobotanical properties. Numerous studies have demonstrated that its essential oil (Mv-EO) presents antimicrobial capacity and shows immunomodulating and anti-allergic properties in human cell lines. Thus, the goal of this study was to investigate the main chemical composition, analyzed by GC–FID, and the cyto-genotoxic effects of Mv-EO, using Vero cells, human PBMCs and mice bone marrow cells. The Mv-EO was rich in pulegone 60.5% and menthone 18.2%. Our results clearly show that Mv-EO is not cyto-genotoxic in vitro nor in vivo. It not induced cytotoxic effects, as indicated by trypan blue dye exclusion and NRU assays both in Vero cells and human PBMCs. In addition, Mv-EO (100–1000 μg/mL) not induced apoptotic effects on human PBMCs, as indicated by Hoechst staining and DNA fragmentation analysis by agarose gel electrophoresis. The in vivo assay showed that Mv-EO (25–500 mg/kg) not increased the frequency of micronucleus in bone marrow cells of mice. Further, the ratio of polychromatic/normochromatic erythrocytes was not modified. These findings suggest that Mv-EO appears to be safe as a therapeutic agent.     

Beneficial effects of Undaria pinnatifida ethanol extract on diet-induced-insulin resistance in C57BL/6J mice

This study was performed to evaluate the beneficial effect of Undaria pinnatifida ethanol extract (UEFx) on insulin resistance in diet-induced obese mice. A high-fat diet was supplemented with the UEFx at 0.69% (wt/wt) dose, which contains an equivalent amount of 0.02% fucoxanthin (wt/wt), or with Fx at 0.02% (wt/wt) dose in diet. After 9 weeks, both UEFx supplement significantly lowered the amount of visceral fat, the size of adipocyte, the fasting blood glucose concentration, the plasma insulin and the insulin resistance index similar to pure as shown by Fx supplement, compared to the high-fat (HF) control group. Blood glucose level was negatively correlated with hepatic glucokinase activity (r = −0.533, p < 0.05), whereas positively correlated with hepatic gluconeogenic enzyme activities (r = 0.463, p < 0.05 for glucose-6-phosphatase; r = 0.457, p < 0.05 for phosphoenolpyruvate carboxykinase). Ratio of hepatic glucokinase/glucose-6-phosphatase and glycogen content were significantly elevated by the UEFx and Fx supplements. Supplementation of the UEFx as well as Fx seemed to stimulate the β-oxidation activity and inhibit the phosphatidate phosphohydrolase activity resulting in a decrease in the hepatic lipid droplet accumulation. The results indicate that the UEFx can prevent insulin resistance and hepatic fat accumulation that is partly mediated by modulating the hepatic glucose and lipid homeostasis in the high fat-induced obese mice.     

Subchronic toxicity and mutagenicity/genotoxicity studies of Irvingia gabonensis extract (IGOB131)

African Bush Mango from Irvingia gabonensis is a West African culinary fruit and the mucilage from this fruit seed is used to make traditional soups and sauces. Extract from the kernel (IGOB131) has been claimed for its health benefits. In the present investigations, potential adverse effects, if any, of IGOB131 were investigated in dose–response 90-day study and genotoxicity studies. In the subchronic study, Sprague Dawley rats (20/sex/group) were gavaged with I. gabonensis extract (IGOB131) at dose levels of 0, 100, 1000 and 2500 mg/kg body weight (bw)/day for 90-days. No treatment-related changes in clinical signs, functional observations, mortality, ophthalmologic observations, body weights, body weight gain or feed consumption were noted. Similarly, hematological, clinical chemistry, urine analysis parameters, and organ weights did not reveal any toxicologically significant treatment-related changes. No treatment-related macroscopic and microscopic abnormalities were noted at the end of treatment period. The mutagenicity as evaluated by Ames assay, in vitro and in vivo chromosomal aberration test and in vivo micronucleus assay did not reveal any genotoxicity of IGOB131. The results of subchronic toxicity study suggest the no-observed-adverse-effect level (NOAEL) for I. gabonensis extract (IGOB131) as ?2500 mg/kg bw/day, the highest dose tested.     

Fucoidan, a sulfated polysaccharide from brown algae, against myocardial ischemia-reperfusion injury in rats via regulating the inflammation response

The aim of the study was to determine the effects of fucoidan on rat myocardial ischemia-reperfusion (I/R) model and elucidate the potential mechanisms. Myocardial I/R injury was induced by the occlusion of left anterior descending coronary artery for 30 min followed by reperfusion for 2 h. After 2 h reperfusion, hemodynamics parameters were detected. Blood samples were collected to determine serum levels of tumor necrosis factor-α (TNF-α) and interleukin 6, 10 (IL-6, 10). Hearts were harvested to assess histopathological changes, infarct size (IS), and the content of myeloperoxidase (MPO). The expression of high-mobility group box 1 (HMGB1), phosphor-IκB-α and phosphor-nuclear factor kappa B (NF-κB) were assayed by western blot. Compared with control group, treatment with fucoidan improved left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP) and the contractility index (P < 0.05, P < 0.01). Fucoidan reduced the myocardial IS, the levels of TNF-α and IL-6, and the activity of MPO (P < 0.05, P < 0.01). Fucoidan down-regulated the expression of HMGB1, phosphor-IκB-α and NF-κB, but increased the content of IL-10 when compared with control (P < 0.05, P < 0.01). Besides, the infiltration of polymorph nuclear leukocytes (PMNs) and histopathological damages in myocardium were decreased in fucoidan treated groups (PMNs, P < 0.05, P < 0.01). These findings revealed that the administration of fucoidan could regulate the inflammation response via HMGB1 and NF-κB inactivation in I/R-induced myocardial damage.