Ameliorative effects of 5-hydroxymethyl-2-furfural (5-HMF) from Schisandra chinensis on alcoholic liver oxidative injury in mice

The effects of Ficus carica on the activity of enzymes related to metabolic syndrome

The present study aimed to investigate the effects of the various parts of Ficus carica L. (figs) on antioxidant, antidiabetic, and antiobesogenic effects in vitro. Fruit, leaves, and stembark of the F. carica plant were sequentially extracted using organic and inorganic solvents and their total polyphenol and flavonoid contents were estimated. The effects of the extracts on antioxidative, antidiabetic (inhibition of α-amylase and α-glucosidase enzymes), and antiobesogenic (antilipase) activities were measured using several experimental models. The fruit ethanolic extract contained a high quantity of polyphenols and flavonoids (104.67±5.51 μg/mL and 81.67±4.00 μg/mL) compared with all other extracts. The activity of the ethanolic extract of F. carica fruit was significantly (p<0.05) higher than all other extracts and parts of the plant in terms of antioxidative, antidiabetic, and antiobesogenic effects. The IC50 values of the fruit ethanolic extract in terms of antioxidative (134.44±18.43 μg/mL), and inhibition of α-glucosidase (255.57±36.46 μg/mL), α-amylase (315.89±3.83 μg/mL), and pancreatic lipase (230.475±9.65 μg/mL) activity indicate that the activity of fruit ethanolic extract is better than all other extracts of the plant. The gas chromatography-mass spectroscopy analysis of the fruit ethanolic extract showed the presence of a number of bioactive compounds such as butyl butyrate, 5-hydroxymethyl furfural, 1-butoxy-1-isobutoxy butane, malic acid, tetradecanoic acid, phytol acetate, trans phytol, n-hexadecanoic acid, 9Z,12Z-octadecadienoic acid, stearic acid, sitosterol, 3,5-dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one, and 2,4,5-trimethyl-2,4-dihydro-3H-pyrazol-3-one. The results of this study suggest that the ethanolic extract of the fruit of F. carica may have potential antidiabetic and antiobesogenic agents.

New insights into the tonifying kidney-yin herbs and formulas for the treatment of osteoporosis

Osteoporosis is characterized by an increasing osseous fragility and fracture resulting from the low mass and deteriorated microarchitecture in the bone tissue. The hormone replacement therapy and alendronate were frequently used to treat osteoporosis as the primary therapeutic strategy, but their adverse effects have severely limited their extensive clinical application, therefore, it is urgent to develop alternative or complementary therapeutic agents for anti-osteoporosis. Interestingly, with more people focusing on the complementary and alternative medicine, traditional Chinese herbs and formulas are being gradually recognized as safe and effective agents in the treatment of osteoporosis. In particular, a notable trend is that increasing studies are making efforts to clarify the anti-osteoporotic effects and mechanism of the tonifying kidney-yin herbs and formulas, a category of agents identified as effective therapy. Therefore, the purpose of this study is to comprehensively review the tonifying kidney-yin herbs and formulas that have been reported in the treatment of osteoporosis as well as how the agents play their roles in detail. This current study not only will advance our understanding of the actions of tonifying kidney-yin herbs and formulas, but also provide new evidence for the clinic use of the tonifying kidney-yin herbs and formulas in the treatment of osteoporosis.

Cardioprotective effects of 5-hydroxymethylfurfural mediated by inhibition of L-type Ca2+ currents

BACKGROUND AND PURPOSE

The antioxidant 5-hydroxymethylfurfural (5-HMF) exerts documented beneficial effects in several experimental pathologies and is currently tested as an antisickling drug in clinical trials. In the present study, we examined the cardiovascular effects of 5-HMF and elucidated the mode of action of the drug.

EXPERIMENTAL APPROACH

The cardiovascular effects of 5-HMF were studied with pre-contracted porcine coronary arteries and rat isolated normoxic-perfused hearts. Isolated hearts subjected to ischaemia/reperfusion (I/R) injury were used to test for potential cardioprotective effects of the drug. The effects of 5-HMF on action potential and L-type Ca2+ current (ICa,L ) were studied by patch-clamping guinea pig isolated ventricular cardiomyocytes.

KEY RESULTS

5-HMF relaxed coronary arteries in a concentration-dependent manner and exerted negative inotropic, lusitropic and chronotropic effects in rat isolated perfused hearts. On the other hand, 5-HMF improved recovery of inotropic and lusitropic parameters in isolated hearts subjected to I/R. Patch clamp experiments revealed that 5-HMF inhibits L-type Ca2+ channels. Reduced ICa,L density, shift of ICa,L steady-state inactivation curves toward negative membrane potentials and slower recovery of ICa,L from inactivation in response to 5-HMF accounted for the observed cardiovascular effects.

CONCLUSIONS AND IMPLICATIONS

Our data revealed a cardioprotective effect of 5-HMF in I/R that is mediated by inhibition of L-type Ca2+ channels. Thus, 5-HMF is suggested as a beneficial additive to cardioplegic solutions, but adverse effects and contraindications of Ca2+ channel blockers have to be considered in therapeutic application of the drug.

Schisandra sphenanthera extract (Wuzhi Tablet) protects against chronic-binge and acute alcohol-induced liver injury by regulating the NRF2-ARE pathway in mice

Alcohol abuse leads to alcoholic liver disease and no effective therapy is currently available. Wuzhi Tablet (WZ), a preparation of extract from Schisandra sphenanthera that is a traditional hepato-protective herb, exerted a significant protective effect against acetaminophen-induced liver injury in our recent studies, but whether WZ can alleviate alcohol-induced toxicity remains unclear. This study aimed to investigate the contribution of WZ to alcohol-induced liver injury by using chronic-binge and acute models of alcohol feeding. The activities of ALT and AST in serum were assessed as well as the level of GSH and the activity of SOD in the liver. The expression of CYP2E1 and proteins in the NRF2-ARE signaling pathway including NRF2, GCLC, GCLM, HO-1 were measured, and the effect of WZ on NRF2 transcriptional activity was determined. We found that both models resulted in liver steatosis accompanied by increased transaminase activities, but that liver injury was significantly attenuated by WZ. WZ administration also inhibited CYP2E1 expression induced by alcohol, and elevated the level of GSH and the activity of SOD in the liver. Moreover, the NRF2-ARE signaling pathway was activated by WZ and the target genes were all upregulated. Furthermore, WZ significantly activated NRF2 transcriptional activity. Collectively, our study demonstrates that WZ protected against alcohol-induced liver injury by reducing oxidative stress and improving antioxidant defense, possibly by activating the NRF2-ARE pathway.

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.

Salvianolic acid B protects hepatocytes from H2O2 injury by stabilizing the lysosomal membrane

AIM

To investigate the capability of salvianolic acid B (Sal B) to protect hepatocytes from hydrogen peroxide (H2O2)/carbon tetrachloride (CCl4)-induced lysosomal membrane permeabilization.

METHODS

Cell Counting Kit-8 assay was used to measure cell viability. Apoptosis and death were assayed through flow cytometry. BrdU incorporation was used to detect cell proliferation. Serum alanine aminotransferase activity and liver malondialdehyde (MDA) content were measured. Liver histopathological changes were evaluated using hematoxylin-eosin staining. Lysosomal membrane permeability was detected with LysoTracker Green-labeled probes and acridine orange staining. The levels of protein carbonyl content (PCC), cathepsins (Cat)B/D, and lysosome-associated membrane protein 1 (LAMP1) were evaluated through western blotting. Cytosol CatB activity analysis was performed with chemiluminescence detection. The mRNA level of LAMP1 was evaluated through quantitative real-time polymerase chain reaction.

RESULTS

Results indicated that H2O2 induced cell injury/death. Sal B attenuated H2O2-induced cell apoptosis and death, restored the inhibition of proliferation, decreased the amount of PCC, and stabilized the lysosome membrane by increasing the LAMP1 protein level and antagonizing CatB/D leakage into the cytosol. CCl4 also triggered hepatocyte death. Furthermore, Sal B effectively rescued hepatocytes by increasing LAMP1 expression and by reducing lysosomal enzyme translocation to the cytosol.

CONCLUSION

Sal B protected mouse embryonic hepatocytes from H2O2/CCl4-induced injury/death by stabilizing the lysosomal membrane.

Nephroprotective Effects of Saponins from Leaves of Panax quinquefolius against Cisplatin-Induced Acute Kidney Injury

Although cisplatin is an anticancer drug that has activity against malignant tumor, it often causes nephrotoxicity. Previous reports have confirmed that the saponins from the leaves of P. quinquefolium (PQS) exerted many pharmacological activities. However, the renoprotective effects of PQS were still unknown. The purpose of the present research was to discuss renoprotective effect of PQS in a mouse model of cisplatin-induced acute kidney injury (AKI). The levels of blood urea nitrogen (BUN) and serum creatinine (CRE) were evidently increased in cisplatin-intoxicated mice, which were reversed by PQS. Renal oxidative stress, evidenced by increased malondialdehyde (MDA) level and decline of glutathione (GSH) and superoxide dismutase (SOD) activities, was significantly alleviated by PQS pretreatment. The suppression of inflammatory response by PQS was realized through the decrease the mRNA expression levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in kidney tissues, which were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Simultaneously, the overexpression of cytochrome P450 E1 (CYP2E1) and heme oxygenase-1 (HO-1) were attenuated by PQS. Furthermore, the effects of Western blotting demonstrated that PQS administration significantly suppressed the protein expression levels of nicotinamide adenine dinucleotide phosphate oxidase type 4 (Nox4), cleaved Caspase-3, cleaved Caspase-9, Bax, nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS), suggesting the inhibition of apoptosis and inflammation response. Overall, PQS may possess protective effects in cisplatin-induced AKI through suppression of oxidative stress, inflammation and apoptosis.

5-HMF Attenuates Liver Fibrosis in CCl4-Plus-Alcohol-Induced Mice by Suppression of Oxidative Stress

The aim of this study was to investigate the effects of 5-hydroxymethyl-2-furfural (5-HMF) on liver fibrosis induced by carbon tetrachloride (CCl₄) and alcohol. Male ICR mice were treated with CCl₄ dissolved in olive oil (10% v/v, 2.5 μg/L) intraperitoneally (i.p.), and given at a dose of 2.5×10^-5 mg/kg B.W. twice a week for 7 wk. Concurrently, mice received drinking water with or without alcohol. The mice in treatment groups and positive control group were gavaged with 5-HMF (7.5, 15, and 30 mg/kg B.W.) or Huganpian (350 mg/kg B.W.) daily starting in the fourth week and lasting for 4 wk. The blood samples were analyzed for biochemical markers of hepatic injury and tissue samples were subjected for estimation of liver antioxidants and histopathological studies. The concentrations of HA (hyaluronic acid), LN (laminin), CIV (collagen type IV), and MDA (malondialdehyde), as well as the serum levels of ALT (alanine aminotransferase) and AST (aspartate aminotransferase) were markedly reduced by 5-HMF. On the other hand, enzymatic antioxidants SOD (superoxide dismutase), CAT (catalase) and GSH-Px (glutathione peroxidase) were markedly elevated in liver tissue treated with 5-HMF. Histopathological examination revealed that 5-HMF treatment noticeably prevented hepatocyte apoptosis, fatty degeneration and inflammatory cell infiltration on liver fibrosis induced by CCl₄ and alcohol. Hoechst 33258 staining also revealed hepatocyte apoptosis. 5-HMF could exert protective effects against liver injury and reduce liver fibrosis induced by CCl₄ and alcohol in mice.

5-HMF attenuates striatum oxidative damage via Nrf2/ARE signaling pathway following transient global cerebral ischemia

Recent studies have shown 5-hydroxymethyl-2-furfural (5-HMF) has favorable biological effects, and its neuroprotection in a variety of neurological diseases has been noted. Our previous study showed that treatment of 5-HMF led to protection against permanent global cerebral ischemia. However, the underlying mechanisms in cerebral ischemic injury are not fully understood. This study was conducted to investigate the neuroprotective effect of 5-HMF and elucidate the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway mechanism in the striatum after transient global cerebral ischemia. C57BL/6 mice were subjected to bilateral common carotid artery occlusion for 20 min and sacrificed 24 h after reperfusion. 5-HMF (12 mg/kg) or an equal volume of vehicle was intraperitoneally injected 30 min before ischemia and 5 min after the onset of reperfusion. At 24 h after reperfusion, neurological function was evaluated by neurological disability status scale, locomotor activity test and inclined beam walking test. Histological injury of the striatum was observed by cresyl violet staining and terminal deoxynucleotidyl transferase (TdT)-mediated dNTP nick end labeling (TUNEL) staining. Oxidative stress was evaluated by the carbonyl groups introduced into proteins, and malondialdehyde (MDA) levels. An enzyme-linked immunosorbent assay (ELISA)-based measurement was used to detect Nrf2 DNA binding activity. Nrf2 and its downstream ARE pathway protein expression such as heme oxygenase-1, NAD (P)H:quinone oxidoreductase 1, glutamate-cysteine ligase catalytic subunit and glutamate-cysteine ligase modulatory subunit were detected by western blot. Our results showed that 5-HMF treatment significantly ameliorated neurological deficits, reduced brain water content, attenuated striatum neuronal damage, decreased the carbonyl groups and MDA levels, and activated Nrf2/ARE signaling pathway. Taken together, these results demonstrated that 5-HMF exerted significant antioxidant and neuroprotective effects following transient cerebral ischemia, possibly through the activation of the Nrf2/ARE signaling pathway.

Effects of Huang Qi Decoction on Endothelial Dysfunction Induced by Homocysteine

Vascular endothelial dysfunction can be induced by homocysteine (Hcy) through promoted oxidative stress. Huang Qi decoction (HQD) is a traditional Chinese medical formula and its components possess antioxidant effect. The study herein was therefore designed to investigate the effects of HQD at different dosage on endothelial dysfunction induced by Hcy. Tempol and apocynin were used to investigate whether antioxidant mechanisms were involved. Endothelium-dependent relaxation of rat aortas was investigated by isometric tension recordings. Reactive oxygen species (ROS) in human umbilical vein endothelial cells (HUVECs) was determined by DHE staining. The assessment related to oxidative stress and NO bioavailability was performed by assay kits and western blot. In isometric tension experiment, HQD at the dose of 30 or 100 μg/mL, tempol, or apocynin prevented impaired endothelium-dependent relaxation in isolated aortas elicited by Hcy. In cellular experiments, substantial enhancement in NADPH oxidase and ROS generation and reduction in NO bioavailability triggered by Hcy were reversed by pretreatment of HQD at the dose of 100 μg/mL, tempol, or apocynin. The results proved that HQD at an appropriate dosage presented favorable effects on endothelial dysfunction initiated by Hcy through antioxidant mechanisms. HQD can act as a potent prescription for the treatment of endothelium related vascular complications.

58-F, a flavanone from Ophiopogon japonicus, prevents hepatocyte death by decreasing lysosomal membrane permeability

Lysosome membrane permeabilization (LMP) has been implicated in cell death. In the present study, we investigated the relationship between cell death and H₂O₂-/CCl₄-induced LMP in hepatocytes in vitro and following acute liver injury in vivo. The key finding was that H₂O₂ triggered LMP by oxidative stress, as evidenced by a suppression of LAMP1 expression, a reduction in LysoTracker Green and AO staining, and the leakage of proton and cathepsin B/D from the lysosome to the cytoplasm, resulting in cell death. CCl₄ also triggered hepatocyte death by decreasing lysosome LAMP1 expression and by inducing the accumulation of products of peroxidative lipids and oxidized proteins. Furthermore, a novel compound 5,8-dimethoxy-6-methyl-7-hydroxy-3-3(2-hydroxy-4-methoxybenzyl) chroman-4-one (58-F) was extracted from Ophiopogon japonicus and served as a potential therapeutic drug. In vivo and in vitro results showed that 58-F effectively rescued hepatocytes by decreasing LMP and by inducing lysosomal enzyme translocation to the cytosol.

Insect tea extract attenuates CCl4-induced hepatic damage through its antioxidant capacities in ICR mice

The Insect tea extract (ITE) contained many polyphenols, the aim of the present study was to determine the preventive effects of ITE on CCl₄-induced hepatic damage in mice. ITE treated mice could reduce hepatic injury compared to the control mice. The 200 mg/kg ITE increased TC, ALB, SOD, CAT, GSH-Px serum levels, and decreased ALT, AST, ALP, TG, BUN, NO, MDA levels compared to the control group. By histological observation, ITE reduced injury to hepatic cells, and these effects were close to that seen with the drug silymarin. The antioxidant related mRNA and protein expressions of Mn SOD, Gu/Zn SOD, CAT, and GSH-Px increased with ITE treatment in hepatic damage mice. ITE treated mice also showed higher IκB-α mRNA and protein expression, and lower NF-κB-p65, iNOS, COX-2 expressions than those of control mice. These results proved ITE has a prophylactic effect in protecting against hepatic injury through the antioxidant capacities.