Assessing the effect of 5-hydroxymethylfurfural on selected components of immune responses in mice immunised with ovalbumin

BACKGROUND

5-Hydroxymethylfurfural (5-HMF) is one of the most important products of the Maillard reaction. In recent years, many profitable biological effects of this compound have been demonstrated. This study sought to elucidate the anti-allergic effect of 5-HMF by investigating some selected components of the immune response in BALB/c mice immunised with ovalbumin (OVA).

RESULTS

Immunised animals had an increased level of serum total and OVA-specific antibodies when compared to the control (P < 0.01).We found that the OVA-induced increase in serum IgE and OVA-specific IgE were significantly suppressed in the groups treated with 5-HMF (P < 0.05). Moreover, interleukin-4 (IL-4) and interferon gamma (IFN-γ) were significantly reduced in a dose-independent manner when compared to the sensitised group (P < 0.05).

CONCLUSION

5-HMF inhibited the up-regulation of total and OVA-specific IgE through the suppression of the Th2-type immune response in immunised BALB/c mice. 5-HMF could therefore be a novel therapeutic approach for the prevention of IgE-mediated allergic diseases. © 2017 Society of Chemical Industry.

Genotoxicity of three food processing contaminants in transgenic mice expressing human sulfotransferases 1A1 and 1A2 as assessed by the in vivo alkaline single cell gel electrophoresis assay

The food processing contaminants 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 5-hydroxymethylfurfural (HMF) and 2,5 dimethylfuran (DMF) are potentially both mutagenic and carcinogenic in vitro and/or in vivo, although data on DMF is lacking. The PHIP metabolite N-hydroxy-PhIP and HMF are bioactivated by sulfotransferases (SULTs). The substrate specificity and tissue distribution of SULTs differs between species. A single oral dose of PhIP, HMF or DMF was administered to wild-type (wt) mice and mice expressing human SULT1A1/1A2 (hSULT mice). DNA damage was studied using the in vivo alkaline single cell gel electrophoresis (SCGE) assay. No effects were detected in wt mice. In the hSULT mice, PhIP and HMF exposure increased the levels of DNA damage in the liver and kidney, respectively. DMF was not found to be genotoxic. The observation of increased DNA damage in hSULT mice compared with wt mice supports the role of human SULTs in the bioactivation of N-hydroxy-PhIP and HMF in vivo.

An improved method for the determination of 5-hydroxymethylfurfural in Shenfu injection by direct analysis in real time-quadrupole time-of-flight mass spectrometry

The emergence of direct analysis in real time (DART) ion source provides the great possibility for rapid analysis of hazardous substance in drugs. DART mass spectrometry (DART-MS) enabled the conducting of a fast and non-contact analysis of various samples, including solid or liquid ones, without complex sample preparation or chromatographic separation. In this study, a modified DART-quadrupole time-of-flight mass spectrometry (DART-QTOF-MS) method was developed for identification and determination of 5-hydroxymethylfurfural (5-HMF) in Shenfu (SF) injection. The quantitative transfer of sample solution was introduced to the glass tips of DIP-it sampler at a fixed volume, which significantly increases the repeatability and accuracy of analytical results. The protonated ion of dibutyl phthalate in the atmosphere was used as the reference mass for TOF-MS recalibration during the data acquisition for constant high accuracy mass measurements. Finally, the developed DART-MS method was used to determine 5-HMF in seven batches of SF injection, and the contents of 5-HMF were not higher than 100 µg/mL. The results obtained were further confirmed by an ultra-high performance liquid chromatography combined with triple quadrupole mass spectrometer (UHPLC-QQQ-MS). The overall results demonstrated that the DART-QTOF-MS method could be applied as an alternative technique for rapid monitoring 5-HMF in herbal medicine injection. Copyright © 2015 John Wiley & Sons, Ltd.

Efficacy and tolerability of a cream containing AR-GG27® (sorbityl furfural palmitate) in the treatment of mild/moderate childhood atopic dermatitis associated with pityriasis alba. A double-blind, placebo-controlled clinical trial

AIM

Pityriasis alba (PA) is a skin disorder characterized by finely scaly, hypopigmented patches, typical of childhood, that also represents an atopic dermatitis (AD) minor sign according to Hanifin and Rajka criteria. It may be isolated or associated with AD representing, sometimes an atypical manifestation of AD during the long-term follow-up of the disease. Aim of the study was to evaluate of the efficacy and tolerability of AR-GG27® (sorbityl furfural palmitate) cream in the treatment of childhood mild or moderate AD associated with PA.

METHODS

The trial is a single center, double-blind, randomized, placebo-controlled study. The study included patients of both sexes, aged between two months and 15 years, suffering from mild and moderate AD always associated with PA. Xerosis was present in all patients. The treatment with topical steroids or topical calcineurin inhibitors (TIMs) had to be suspended for at least 15 days. Any systemic therapy and phototherapy or sun exposure were withdrawn at least 30 days before. Emollients were stopped at least seven days before. During the trial, no other local or systemic treatments were allowed, as well as sun exposure. Patients affected by AD with viral, bacterial or fungal overinfection or patients with diabetes mellitus, severe systemic diseases or intolerance to one or more components of the product were excluded. The primary endpoint was the evaluation of the average change in the Investigator Global Assessment (IGA) after 15 and 30 days of treatment. The second endpoint was the evaluation of severity of three different clinical signs: erythema, excoriation desquamation, using a subjective five-point scale. Changes in pruritus severity was also considered during the entire period of treatment, through the use of a Visual Analogue Scale (VAS). A P<0.05, two tailed was considered as statistically significant.

RESULTS

After 15 and 30 days there was a statistically significant difference in the group treated with AR-GG27®, compared to the placebo (respectively, P=0.0007 and P=0.005). After 15 days of treatment, itching was clearly reduced in AR-GG27® treated group compared with the placebo, both in the study population (P=0.01) and in patients where the symptom was present from the beginning (P=0.05).

CONCLUSION

AR-GG27® showed a beneficial action associated with high compliance and tolerability in dermatological skin conditions characterized by inflammation and tissue oxidative stress in children, as PA with mild and moderate AD.

[Effect of 5-hydroxymethyl furfural on BCL-2 and NF-kappaB gene expression of apoptotic rat hippocampal neurons injured by H2O2]

OBJECTIVE

To investigate the effect of 5-hydroxymethyl furfural (5-HMF) on apoptosis and BCL-2, NF-kappaB gene expression of rat hippocampal neurons injured by hydroperoxide (H2O2).

METHODS

Hippocampal neurons of newly born rat were cultured in vivo and injured by H2O2. Effect of different concentration of 5-HMF on cell viability was measured by MTT. Flow cytometer (FCM) was used to measure the apoptosis of rat hippocampal neurons pre-cultured with different concentration of 5-HMF,Western blotting was used to measure the expression of BCL-2 and NF-kappaB gene.

RESULTS

It revealed that the high and medium dosage of 5-HMF could increase the activity of rat hippocampal. The high, medium and low dosage of 5-HMF also increased the expression of BCL-2 gene and decreased the expression of NF-kappaB gene.

CONCLUSION

5-HMF could restrain the apoptosis of cultured hippocampal neurons injured by H2O2. The mechanism may be related to increasing in BCL-2 level and decreasing in NF-kappaB level.

The impact of preoperative micronutrient supplementation in lung surgery. A prospective randomized trial of oral supplementation of combined alpha-ketoglutaric acid and 5-hydroxymethylfurfural

OBJECTIVE

Preoperative micronutrient supplementation in fast-track surgery programs have shown to reduce complications, shorten recovery, and thereby lower costs. In a prospective randomized study, the metabolic effects of a combination of alpha-ketoglutaric acid (alpha-KG) and 5-hydroxymethylfurfural (5-HMF) were evaluated concerning their impact on improvement of exercise capacity and reduction of oxidative stress in lung surgery.

METHODS

Thirty-two consecutive patients admitted for lung resection due to NSCLC were randomized to the study protocol. All patients received preoperative nutritional guidelines according to general recommendations. In 16 (study group), a supplementation of 7.2g alpha-KG and 720 mg 5-HMF/day (SANOPAL) was administered from days 1 to 10. Spiroergometric evaluation was carried out at baseline and day 10 after micronutrient supplementation. Blood samples for the determination of oxidative stress, i.e. carbonyl proteins (CPs) and isoprostanes (IPs) were taken on at baseline, in the operating room just before resection treatment, and 25 min after single lung ventilation (SLV).

RESULTS

Spiroergometric re-evaluation showed a significant increase of VO2max (p=0.0108) and Watt's (p=0.011) in favor of the study group. Determination of oxidative stress showed a significant reduction of CPs before (p=0.048) and after SLV (p=0.0001) for the study group compared to the control group. The same is true for IPs before (p=0.003) and after SLV (p=0.02). Hospitalization and intensive care unit (ICU) of the study group showed a significant reduction compared to the control group (p=0.03 and p=0.02, respectively).

CONCLUSIONS

Simple oral supplementation using a combination of alpha-KG and 5-HMF of preoperative micronutrition may therefore be one further step in a multimodality approach of fast-track surgery programs also in lung surgery.

Diets rich in Maillard reaction products affect protein digestibility in adolescent males aged 11-14 y

BACKGROUND

Adolescents are nutritionally at risk because of their physiologic needs and dietary habits. Maillard reaction products (MRPs) are widely consumed by this population, mainly as a result of their high intake of fast food and snacks.

OBJECTIVE

We compared the effects of diets with different MRP contents on dietary protein utilization in adolescent males aged 11-14 y. The brown diet (BD) was rich and the white diet (WD) was poor in MRP content (hydroxymethylfurfural: 3.87 and 0.94 mg/kg; fluorescence intensity: 21.04% and 7.31%, respectively).

DESIGN

In a 2-period crossover trial, 18 healthy adolescent males were randomly assigned to 2 groups. The first group consumed the WD for 2 wk, observed a 40-d washout period, and then consumed the BD for 2 wk. The second group received the diets in the opposite order. Subjects collected urine and feces on the last 3 d of each dietary period. Fasting blood samples were collected after both periods.

RESULTS

Compared with consumption of the WD, consumption of the BD resulted in 47% higher fecal nitrogen fecal excretion (P = 0.002), 12% lower apparent nitrogen absorption (P = 0.000), and a 6% lower nitrogen digestibility (P = 0.000). The apparent nitrogen retention and the utilization of ingested nitrogen did not differ significantly between the diets, although values after the BD tended to decrease. Serum biochemical variables related to nitrogen metabolism did not differ significantly.

CONCLUSIONS

The consumption of a diet rich in MRPs negatively affects protein digestibility. The possible effects of an excessive intake of MRPs during adolescence warrant attention, and long-term effects should be considered.

Effects of glucose, fructose and 5-hydroxymethyl-2-furaldehyde on the presystemic metabolism and absorption of glycyrrhizin in rabbits

Our previous study reported that co-administration of honey significantly increased the serum levels of glycyrrhetic acid (GA) after oral administration of glycyrrhizin (GZ) in rabbits. The components of honey are sucrose, glucose, fructose and 5-hydroxymethyl-furaldehyde (HMF). To clarify the causative component(s) in honey that altered the metabolic pharmacokinetics of GZ, rabbits were given GZ (150 mg kg(-1)) with and without glucose (5 g/rabbit), fructose (5 g/rabbit) and HMF (1 mg kg(-1)), respectively, in crossover designs. An HPLC method was used to determine concentrations of GZ and GA in serum as well as GA and 3-dehydroglycyrrhetic acid (3-dehydroGA) in faeces suspension. A noncompartment model was used to calculate the pharmacokinetic parameters and analysis of variance was used for statistical comparison. Our results indicated that the area under curve (AUC) of GA was significantly increased by 29% when HMF was coadministered, whereas the pharmacokinetics of GZ and GA were not significantly altered by coadministration of glucose or fructose. An in-vitro study, using faeces to incubate GZ and GA individually, indicated that HMF significantly inhibited the oxidation of GA to 3-dehydroGA and this may explain the enhanced GA absorption in-vivo. It was concluded that HMF is the causative component in honey that affects the presystemic metabolism and pharmacokinetics of GZ in-vivo.

Subacute (28-day) toxicity of furfural in Fischer 344 rats: a comparison of the oral and inhalation route

The subacute oral and inhalation toxicity of furfural vapour was studied in Fischer 344 rats to investigate whether route-to-route extrapolation could be employed to derive the limit value for inhalation exposure from oral toxicity data. Groups of 5 rats per sex were treated by gavage daily for 28 days at dose levels of 6-192 mg/kg bw/day, or exposed by inhalation to concentrations of 20-1280 mg/m3 (6 h/day, 5 days/week) or 160-1280 mg/m3 (3 h/day, 5 days/week) for 28 days. Controls received vehicle (corn oil) or were exposed to clean air. Daily oral treatment with the highest dose of furfural (initially 192 mg/kg bw/day, later reduced to 144 mg/kg bw/day and finally to 120 mg/kg bw/day) resulted in mortality, and in increases in absolute and relative kidney and liver weight in surviving females of this group. Exposure of rats by inhalation for 6 h/day, 5 days/week for 28 days induced mortality at concentrations of 640 mg/m3 and above within 1-8 days. At 640 mg/m3 (3 h/day) and at 320 mg/m3 (3 and 6 h/day) and below, however, exposure was tolerated without serious clinical effects. In contrast, histopathological nasal changes were seen even at the lowest concentration of 20 mg/m3. With increasing exposure concentration, the nasal effects increased in incidence and severity and also expanded from the anterior part to the posterior part, including the olfactory epithelium. It was concluded that the no-observed-adverse-effect level (NOAEL) for oral toxicity was 96 mg/kg bw/day. The NOAEL for systemic inhalation toxicity was comparable, i.e. 92 mg/kg bw/day (corresponding to 320 mg/m3 (6 h/day) or 640 mg/m3 (3 h/day)) assuming 100% absorption. The presence of the histopathological nasal changes at the lowest tested concentration of 20 mg/m3 (corresponding to 6 mg/kg bw/day) proves that for locally acting substances like furfural extrapolation from the oral to the inhalation route is not valid.

In vitro anti-tyrosinase activity of 5-(hydroxymethyl)-2-furfural isolated fromDictyophora indusiata

The inhibition of mushroom tyrosinase by methanolic extract of Dictyophora indusiata was evaluated and the bioactive component was characterized and identified as 5-(hydroxymethyl)-2-furfural (HMF) by chromatographic and spectroscopic means. Kinetic studies revealed it to be a noncompetitive inhibitor for the oxidation of L-DOPA. On the basis of these findings some related analogues were also tested for their anti-tyrosinase activity, in order to gain more insight into structure and activity relationship among these heterocyclic compounds.

Metabolism and excretion of [14C]furfural in the rat and mouse

The fate of furfural (2-furancarboxaldehyde) was investigated in male and female Fischer 344 (F344) rats given single oral doses of 1, 10 and 60 mg/kg and male and female CD1 mice given 1, 20 and 200 mg/kg [carbonyl-14C]furfural. There was a very high recovery (more than 90% of dose) of radioactivity in all dose groups in 72 hr. The major route of elimination was by the urine, with much smaller amounts present in the faeces and exhaled as 14CO2. The residue in the carcass after 72 hr was less than 1% of the administered dose. Furoylglycine and furanacryloylglycine were identified as the major urinary metabolites by high-performance thin-layer chromatography, radio-HPLC, gas chromatography-mass spectrometry and 1H-nuclear magnetic resonance spectroscopy, by comparison with synthetic reference compounds. There were only subtle differences in the metabolic profile as a function of dose size, sex and species. An additional minor polar metabolite was excreted by male rats and mice, and the parent acids of the glycine conjugates were excreted at the higher doses. The results are discussed in terms of the participation of xenobiotics in the chain elongation reactions of fatty acid biosynthesis.

Positive foci of glutathione S-transferase placental form in the liver of rats given furfural by oral administration

We observed GST-P-positive liver foci in rats during the course of developing liver cirrhosis by oral administration of furfural, an organic solvent. Male Wistar rats were given furfural-containing diet (20-30 mg/kg diet) for 15-150 days, and killed 14 days after terminating furfural feeding. Immunohistochemical investigation of GST-P-positive liver foci which appeared in rats fed furfural for more than 30 days revealed an increase in number and size of the foci in proportion to the duration of furfural administration. Since furfural is known not to be carcinogenic in rats, this finding will be helpful to understand the enhancing effect of furfural-induced cirrhosis on chemical hepatocarcinogenesis.

Experimental studies on hepatic cirrhosis and hepatocarcinogenesis. I. Production of hepatic cirrhosis by furfural administration

Changes of the liver following either single or repeated oral administration of furfural were studied histopathologically. Following single administration, the livers showed scattered eosinophilic globular formation and increased mitotic figures without zonal or massive necrosis. Both changes were most prominent 6 hours after administration, gradually decreasing in number thereafter. In the repeated administration experiment, furfural was mixed with basal diet for 90 or 120 days. The livers on the 90th day showed cirrhotic changes with formation of pseudolobules, widening of Glisson's sheath, and destruction of limiting plates. In the parenchyma bridging necrosis and hydropic degeneration of hepatocytes were striking. In the livers on the 120th day, pseudolobule formation was more prominent but parenchymal damage was reduced. No cancerous or precancerous changes were observed. Cirrhotic changes seen in the chronic experiment resembled Nagayo-Miyake's A' type hepatic cirrhosis in man, and the result suggested that furfural-induced hepatic cirrhosis is an appropriate model for studying the interrelation between hepatic cirrhosis and hepatocarcinogenesis.