Hepatoprotective and antioxidant activity of ethanolic extracts of edible lotus (Nelumbo nucifera Gaertn.) leaves

Polysaccharides from Angelica and Astragalus exert hepatoprotective effects against carbon-tetrachloride-induced intoxication in mice

This study aimed to investigate the effects of polysaccharide from Angelica and Astragalus (AAP) on carbon tetrachloride (CCl4) induced liver damage in mice. A total of 120 Kunming mice were randomly distributed among 6 groups comprising (i) the normal control mice, (ii) the CCl4 treatment group, (iii) the bifendate treatment group, (iv) the AAP treatment group, (v) the Angelica sinensis polysaccharide (ASP) treatment group, and (vi) the Astragalus membranaceus polysaccharide (AMP) treatment group. AAP, ASP and AMP were administered to mice treated with CCl4. The activities of alanine transaminase (ALT) and aspartate transaminase (AST) in the serum, and superoxide dismutase (SOD) and malondialdehyde (MDA) in the liver tissues were quantified, as well as the liver index. Hepatic histological changes were observed by staining liver sections with hematoxylin and eosin. Our results show that bifendate, AAP, ASP, and AMP significantly decreased the activities of MDA, AST, and ALT, and enhanced the activity of SOD in CCl4-treated mice. Bifendate, AAP, ASP, and AMP consistently ameliorated the liver injuries induced with CCl4. Notably, the hepatoprotective effect of AAP was stronger than that of bifendate, ASP, or AMP. In addition, AAP alleviated liver inflammation and decreased the liver indexes of mice induced with CCl4. These effects were at least partly due to the antioxidant properties of AAP in scavenging free radicals to ameliorate oxidative stress and to inhibit lipid peroxidation.

Protective effects of Chaenomeles thibetica extract against carbon tetrachloride-induced damage via the MAPK/Nrf2 pathway

Chaenomeles thibetica extract possesses antioxidant and hepatoprotective effects against carbon tetrachloride-induced damage via the MAPK/Nrf2 pathway.

Light response and potential interacting proteins of a grape flavonoid 3'-hydroxylase gene promoter

Flavonoid 3'-hydroxylase (F3'H), a member of cytochrome P450 protein family, introduces B-ring hydroxyl group in the 3' position of the flavonoid. In this study, the cDNA sequence of a F3'H gene (VviF3'H), which contains an open reading frame of 1530 bp encoding a polypeptide of 509 amino acids, was cloned and characterized from Vitis vinifera L. cv. Cabernet Sauvignon. VviF3'H showed high homology to known F3'H genes, especially F3'Hs from the V. vinifera reference genome (Pinot Noir) and lotus. Expression profiling analysis using real-time PCR revealed that VviF3'H was ubiquitously expressed in all tested tissues including berries, leaves, flowers, roots, stems and tendrils, suggesting its important physiological role in plant growth and development. Moreover, the transcript level of VviF3'H gene in grape berries was relatively higher at early developmental stages and gradually decreased during véraison, and then increased in the mature phase. In addition, the promoter of VviF3'H was isolated by using TAIL-PCR. Yeast one-hybrid screening of the Cabernet Sauvignon cDNA library and subsequent in vivo/vitro validations revealed the interaction between VviF3'H promoter and several transcription factors, including members of HD-Zip, NAC, MYB and EIN families. A transcriptional regulation mechanism of VviF3'H expression is proposed for the first time.

Hepatoprotective activity of flavonoids from Cichorium glandulosum seeds in vitro and in vivo carbon tetrachloride-induced hepatotoxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Cichorium glandulosum Boiss. et Huet was used historically in Uyghur folk medicine. Its roots, seeds, and aerial parts are extensively used by Uyghur residents in Xinjiang to eliminate savda typhoid, dredge and cure obstructive jaundice variety liver disorders.

AIM OF THE STUDY

To evaluate the hepatoprotective activity of total flavonoids (TFs) obtained from C. glandulosum seeds against carbon tetrachloride (CCl4)-induced liver damage in vitro and in vivo. To investigate the mechanisms of hepatoprotective effects for TFs.

MATERIALS AND METHODS

The dried seeds of C. glandulosum were extracted with 70% aqueous ethanol, and the extract was chromatographed with D101 macroporous resin. In vitro the antioxidant capacity against lipid peroxidation (LPO) was evaluated using ferrothiocyanate, thiobarbituric acid, β-carotene bleaching, and LPO inhibition assay. The cytotoxicity and hepatoprotective activity of TFs were evaluated in human liver hepatoma cells (HepG2). MTT assay, hepatic injury markers aspartate aminotransferase (AST), alanine aminotransaminase (ALT), lactate dehydrogenase (LDH) leakage, malondialdehyde (MDA), and glutathione (GSH) were performed. In vivo the hepatoprotective activity of TFs against CCl4-induced acute liver injury was evaluated in rats. A series of biochemical and antioxidant parameter levels were measured in liver homogenate. The suppressive effect on pancreatic lipase activity was determined.

RESULTS

Results indicated that TFs showed antioxidant capacity against lipid peroxidation (LPO). Administrating CCl4 (1%, v/v) caused a significant decrease in HepG2 viability. Treatment with TFs at doses (62.5, 125, and 250 μg/ml) could significantly ameliorate the cytotoxicity and decline the levels of AST, ALT, and LDH induced by CCl4. The markers including MDA and GSH, which were close to oxidative damage, were restored. Oral treatment with TFs in vivo at doses of 100, 200, and 400 mg/kg significantly reduced the levels of AST, ALT, alkaline phosphatase (ALP), total bilirubin (TB), and thiobarbituric acid reactive substances (TBARs) in the serum compared with CCl4-induced acute liver injury in rats. TFs showed dose-dependent suppressive effects on pancreatic lipase activity, and the IC50 was 1.318 ± 0.164 mg/ml.

CONCLUSION

TFs from C. glandulosum seeds demonstrated significant hepatoprotection against CCl4-induced hepatotoxicity. TFs exhibited significant suppression of LPO and pancreatic lipase capacity, which may be the mechanisms of hepatoprotective effects against CCl4. Our results contribute towards validation of the traditional use of C. glandulosum seeds in the treatment of liver disorders.

Antioxidant, Hepatoprotective Potential and Chemical Profiling of Propolis Ethanolic Extract from Kashmir Himalaya Region Using UHPLC-DAD-QToF-MS

The aim of this study was to examine hepatoprotective effect of ethanolic extract of propolis (KPEt) from Kashmir Himalaya against isoniazid and rifampicin (INH-RIF) induced liver damage in rats. Hepatic cellular injury was initiated by administration of INH-RIF combination (100 mg/kg) intraperitoneal (i.p.) injection for 14 days. We report the protective effects of KPEt against INH-RIF induced liver oxidative stress, inflammation, and enzymatic and nonenzymatic antioxidants. Oral administration of KPEt at both doses (200 and 400 mg/kg body weight) distinctly restricted all modulating oxidative liver injury markers and resulted in the attenuation of INH-RIF arbitrated damage. The free radical scavenging activity of KPEt was evaluated by DPPH, nitric oxide, and superoxide radical scavenging assay. The components present in KPEt identified by ultra high performance liquid chromatography diode array detector time of flight-mass spectroscopy (UHPLC-DAD-QToF-MS) were found to be flavonoids and phenolic acids. The protective efficacy of KPEt is possibly because of free radical scavenging and antioxidant property resulting from the presence of flavonoids and phenolic acids.

Photoprotective Effect of Lotus (Nelumbo nucifera Gaertn.) Seed Tea against UVB Irradiation

Lotus (Nelumbo nucifera Gaertn.) seed is widely used as a traditional medicine in countries of Asia. Among many functions of the lotus seed, one interesting activity is its skin protection from the sunlight and scar. In this study, we focused on the skin protective property of lotus seed tea against ultraviolet B (UVB) irradiation. Two groups of a hairless mouse model, water as control (water group) and lotus seed tea (LST group), were administrated a fluid drink water for six months. After 6 month of administration, UVB exposure was carried out to both groups for another 3 months. During and after the administration, the skin moisture content and the morphological and histopathological analyses through biopsy were carried out. Prior to UVB irradiation, no significant difference was discovered in the skin moisture content for the water group and LST group (P<0.05). However, drastic changes were observed after the UVB treatment. The LST group showed a clear evidence of skin protection compared to the control group (P<0.05). The moisture content, epidermal and horny layer thickness, and protein carbonyl values all revealed that the intake of the lotus seed tea enhanced protection against UVB exposure. As a result, the long-term intake of the lotus seed tea showed the effect of preventing loss of skin moisture, mitigating the formation of abnormal keratinocytes, and contributing to protein oxidation inhibition.

Analysis of Flavonoids in Lotus (Nelumbo nucifera) Leaves and Their Antioxidant Activity Using Macroporous Resin Chromatography Coupled with LC-MS/MS and Antioxidant Biochemical Assays

Lotus (Nelumbo nucifera) leaves, a traditional Chinese medicinal herb, are rich in flavonoids. In an effort to thoroughly analyze their flavonoid components, macroporous resin chromatography coupled with HPLC-MS/MS was employed to simultaneously enrich and identify flavonoids from lotus leaves. Flavonoids extracted from lotus leaves were selectively enriched in the macroporous resin column, eluted subsequently as fraction II, and successively subjected to analysis with the HPLC-MS/MS and bioactivity assays. Altogether, fourteen flavonoids were identified, four of which were identified from lotus leaves for the first time, including quercetin 3-O-rhamnopyranosyl-(1→2)-glucopyranoside, quercetin 3-O-arabinoside, diosmetin 7-O-hexose, and isorhamnetin 3-O-arabino- pyranosyl-(1→2)-glucopyranoside. Further bioactivity assays revealed that these flavonoids from lotus leaves possess strong antioxidant activity, and demonstrate very good potential to be explored as food supplements or even pharmaceutical products to improve human health.

Potential assessment of Rumex vesicarius L. as a source of natural antioxidants and bioactive compounds

The present work is designed to evaluate the antioxidant activities of hydroalcoholic extract (HAE) and its fractions (viz., hexane (HF), chloroform (CF), ethyl acetate (AF), n-butanol (BF) and water (WF)) obtained from aerial part of Rumex vesicarius L. by using different in vitro antioxidant assays. The content in pigments (carotenoids and chlorophylls), total phenolics, flavonoids and tannins were determined using spectrophotometric methods. Qualitative analyses of major phenolics by TLC analysis were also evaluated. Experimental results obtained show that R. vesicarius is a rich source of β-carotene (116.83 ± 1.60 μg/g DW), lycopene (156.40 ± 1.59 μg/g DW) and chlorophyll a (271.45 ± 3.46 μg/g DW). The greatest antioxidant activity was found in AF (IC50.DPPH = 0.07 ± 0.00 mg/ml) followed by BF and CF (0.15 ± 0.00 and 0.16 ± 0.00 mg/ml, respectively). These fractions were also better in their effect on reducing the oxidation of β-carotene. Reducing power of crude methanol extract/fractions increased with increasing concentration of the extract. The amount of total phenolics varied from 0.37 ± 0.01 to 43.28 ± 0.28 mg GAE/g of dry weight, HAE had the higher content (43.28 ± 0.28 mg GAE/g of DW). A negative correlation was found between phenolic compounds and the antioxidant efficiencies of the crude extract/fractions, suggesting that phenolic compounds are not the only contributors to the antioxidant activities of Rumex vesicarius. The present findings suggest that Rumex vesicarius L. can be used as natural antioxidant source to prevent damage associated with free radicals.

Antioxidant and Cytoprotective Effects of Lotus (Nelumbo nucifera) Leaves Phenolic Fraction

Phenolic rich ethyl acetate fraction (EAF) from lotus leaves was prepared and its bioactive components, antioxidant and cytoprotective effects were investigated. EAF showed high total phenolic content and flavonoid content and contained rutin (11,331.3±4.5 mg/100 g EAF), catechin (10,853.8±5.8 mg/100 g EAF), sinapic acid (1,961.3±5.6 mg/100 g EAF), chlorogenic acid (631.9±2.3 mg/100 g EAF), syringic acid (512.3±2.5 mg/100 g EAF), and quercetin (415.0±2.1 mg/100 g EAF). EAF exerted the IC50 of 4.46 μg/mL and 5.35 μg/mL toward DPPH and ABTS cation radicals, respectively, and showed strong reducing power, which was better than that of ascorbic acid, a positive control. Additionally, EAF protected hydroxyl radical-induced DNA damage indicated by the conversion of supercoiled pBR322 plasmid DNA to the open circular form and inhibited lipid peroxidation of polyunsaturated fatty acid in a linoleic acid emulsion. In cultured hepatocytes, EAF exerted a cytoprotective effect against oxidative stress by inhibiting intracellular reactive oxygen species formation and membrane lipid peroxidation. In addition, depletion of glutathione under oxidative stress was remarkably restored by treatment with EAF. The results suggest that EAF have great potential to be used against oxidative stress-induced health conditions.

Nuciferine relaxes rat mesenteric arteries through endothelium-dependent and -independent mechanisms

BACKGROUND AND PURPOSE

Nuciferine, a constituent of lotus leaf, is an aromatic ring-containing alkaloid, with antioxidative properties. We hypothesize nuciferine might affect vascular reactivity. This study aimed at determining the effects of nuciferine on vasomotor tone and the underlying mechanism

EXPERIMENTAL APPROACH

Nuciferine-induced relaxations in rings of rat main mesenteric arteries were measured by wire myographs. Endothelial NOS (eNOS) was determined by immunoblotting. Intracellular NO production in HUVECs and Ca(2+) level in both HUVECs and vascular smooth muscle cells (VSMCs) from rat mesenteric arteries were assessed by fluorescence imaging.

KEY RESULTS

Nuciferine induced relaxations in arterial segments pre-contracted by KCl or phenylephrine. Nuciferine-elicited arterial relaxations were reduced by removal of endothelium or by pretreatment with the eNOS inhibitor L-NAME or the NO-sensitive guanylyl cyclase inhibitor ODQ. In HUVECs, the phosphorylation of eNOS at Ser(1177) and increase in cytosolic NO level induced by nuciferine were mediated by extracellular Ca(2+) influx. Under endothelium-free conditions, nuciferine attenuated CaCl2-induced contraction in Ca(2+)-free depolarizing medium. In the absence of extracellular calcium, nuciferine relieved the vasoconstriction induced by phenylephrine and the addition of CaCl2. Nuciferine also suppressed Ca(2+) influx in Ca(2+)-free K(+)-containing solution in VSMCs.

CONCLUSIONS AND IMPLICATIONS

Nuciferine has a vasorelaxant effect via both endothelium-dependent and -independent mechanisms. These results suggest that nuciferine may have a therapeutic effect on vascular diseases associated with aberrant vasoconstriction.

Immunoregulatory and anti-HIV-1 enzyme activities of antioxidant components from lotus (Nelumbo nucifera Gaertn.) rhizome

In the present study, two antioxidant micromolecular components (L2f-2 and L2f-3) and an antioxidant macromolecular component LB2 were extracted from lotus (Nelumbo nucifera Gaertn.) rhizomes. MS, FTIR (Fourier-transform IR) spectroscopy and NMR were used to identify these compounds. L2f-2 was (+/-)-gallocatechin, L2f-3 was (-)-catechin and LB2 was a polysaccharide-protein complex with a molecular mass of 18.8 kDa. LB2 was identified as a polysaccharide sulfate containing α/β-pyranose and α-furanose according to its FTIR spectrogram. It was composed of mannose, rhamnose, glucose, galactose and xylose with a molar ratio 2:8:7:8:1. The antioxidant components L2f-2, L2f-3 and LB2 strongly inhibited HIV-1 RT (reverse transcriptase) and IN (integrase). LB2 inhibited RT with an IC50 value of 33.7 μM. It also exhibited the highest HIV-1 3'-processing inhibitory activity with an IC50 value of 5.28 μM. Both L2f-2 and L2f-3 up-regulated the expression of IL-2 (interleukin-2) and down-regulated IL-10, while LB2 exhibited positive regulation on IL-2, IL-4 and IL-10. Moreover, L2f-3 and LB2 might inhibit HIV-1 directly by down-regulating TNFα (tumour necrosis factor α). These natural antioxidant components with antiviral and immunoregulatory activities could be potentially important for anti HIV-1 drug development and application to HIV-1 therapy.

Nelumbo nucifera leaves protect hydrogen peroxide-induced hepatic damage via antioxidant enzymes and HO-1/Nrf2 activation

Nelumbo nucifera leaves ameliorated hepatotoxicity via antioxidant action.

Response surface optimization and physicochemical properties of polysaccharides from Nelumbo nucifera leaves

Dynamic high pressure microfluidization (DHPM)-assisted extraction (DHPMAE) of lotus (Nelumbo nucifera) leaves polysaccharides (LLPs) was optimized by response surface methodology. The optimal extraction conditions were: liquid/solid ratio of 35:1 (v/m, mL/g), processing pressure of 180 MPa, processed two times, extraction temperature of 76°C, extraction time of 50 min. Under the optimal extraction conditions, DHPMAE produced a higher polysaccharides yield (6.31%) than leaching (2.95%). Scanning electron microscope (SEM) analysis revealed that DHPM could reduce the particles size and make the surface more unconsolidated. The LLPs prepared by both methods showed similar FT-IR spectrum, and were consisted of the same monosaccharides, including rhamnose, fucose, arabinose, xylose, mannose, glucose and galactose. The content of each monosaccharide in extracts, however, was quite different. The average molecular weight of LLPs prepared by DHPMAE is 550 kDa, smaller than 578 kDa obtained by leaching. The LLPs prepared by DHPMAE exhibited stronger DPPH scavenging ability (IC50 value of 0.38 mg/mL), HO scavenging ability (IC50 value of 0.61 mg/mL) and reducing power. Therefore, DHPMAE can be a promising alternative to traditional extraction techniques for polysaccharides from plants, and lotus leaves might be a potential resource of natural antioxidants.

Antioxidant and prophylactic effects of Delonix elata L., stem bark extracts, and flavonoid isolated quercetin against carbon tetrachloride-induced hepatotoxicity in rats

Delonix elata L. (Ceasalpinaceae), is widely used by the traditional medical practitioners of Karnataka, India, to cure jaundice, and bronchial and rheumatic problems. The objective of this study was to screen the in vitro antioxidant and hepatoprotective activity of the stem bark extracts against CCl4-induced liver damage in rats. Among different stem bark extracts tested, the ethanol extract (DSE) has shown significant in vitro antioxidant property in radicals scavenging, metal chelating, and lipid peroxidation inhibition assays. HPLC analysis of the DSE revealed the presence of known antioxidant molecules, namely, gallic acid, ellagic acid, coumaric acid, quercetin, and rutin. Bioassay-guided fractionation of DSE has resulted in the isolation and characterization of quercetin. DSE and quercetin have shown significant prophylactic effects by restoring the liver function markers (AST, ALT, ALP, serum bilirubin, and total protein) and antioxidant enzymes (SOD, CAT, GPx, and GST). These results were proved to be hepatoprotective at par with silymarin and well supported by the histological observations of liver sections with distinct hepatic cells, and mild degree of fatty change and necrosis. The results indicated that the DSE and quercetin were significant for prophylactic activity against CCl4-induced liver damage in rats. This activity could be attributed to the antioxidant constituents in the DSE and hence justified the ethnomedicinal claims.

Anti-obesity and hypolipidaemic effects of Nelumbo nucifera seed ethanol extract in human pre-adipocytes and rats fed a high-fat diet

BACKGROUND

We conducted this investigation in order to examine the anti-obesity and hypolipidaemic effects of Nelumbo nucifera seed ethanol extract (NSEE) in vitro and in vivo.

METHODS

To study the anti-obesity effect of NSEE in vitro and in vivo, human pre-adipocytes were treated with NSEE, and male Sprague-Dawley rats were fed with a normal diet and a high-fat diet with or without NSEE, respectively.

RESULTS

In vitro treatment with NSEE resulted in inhibition of lipid accumulation and decreased expression of peroxisome proliferator-activated receptor gamma (PPARγ), glucose transporter 4 (GLUT4), and leptin in cultured human adipocytes, indicating that it inhibited the differentiation of pre-adipocytes into adipocytes. Administration of NSEE resulted in significantly reduced body weight gain and adipose tissue weights in rats. Serum triglyceride and leptin level of the high-fat diet + NSEE group was significantly lower, compared to the high-fat group.

CONCLUSION

These results demonstrate an inhibitory effect of NSEE on adipogenesis. In addition, NSEE had a beneficial effect, reducing adipose tissue weights, ameliorating blood lipid profile, and modulating serum leptin level in rats fed a high-fat diet. Therefore, we suggest that lotus seed has a potential to be developed as an effective agent against obesity-related diseases.

Identification and comparison of anti-inflammatory ingredients from different organs of Lotus nelumbo by UPLC/Q-TOF and PCA coupled with a NF-κB reporter gene assay

Lotus nelumbo (LN) (Nelumbo nucifera Gaertn.) is an aquatic crop that is widely distributed throughout Asia and India, and various parts of this plant are edible and medicinal. It is noteworthy that different organs of this plant are used in traditional herbal medicine or folk recipes to cure different diseases and to relieve their corresponding symptoms. The compounds that are contained in each organ, which are named based on their chemical compositions, have led to their respective usages. In this work, a strategy was used to identify the difference ingredients and screen for Nuclear-factor-kappaB (NF-κB) inhibitors with anti-inflammatory ability in LN. Seventeen main difference ingredients were compared and identified from 64 samples of 4 different organs by ultra-performance liquid chromatography that was coupled with quadrupole/time of flight mass spectrometry (UPLC/Q-TOF-MS) with principal component analysis (PCA). A luciferase reporter assay system combined with the UPLC/Q-TOF-MS information was applied to screen biologically active substances. Ten NF-κB inhibitors from Lotus plumule (LP) extracts, most of which were isoquinoline alkaloids or flavone C-glycosides, were screened. Heat map results showed that eight of these compounds were abundant in the LP. In conclusion, the LP extracts were considered to have the best anti-inflammatory ability of the four LN organs, and the chemical material basis (CMB) of this biological activity was successfully validated by multivariate statistical analysis and biological research methods.

Protective effects of ethyl acetate fraction of Lawsonia inermis fruits extract against carbon tetrachloride-induced oxidative damage in rat liver

This study aimed to investigate the antioxidant properties of different fractions obtained from the fruits of Lawsonia inermis, a widely used medicinal plant, against carbon tetrachloride (CCl4)-induced oxidative stress in rat liver. The results show that several fractions obtained from L. inermis fruits possessed important antioxidant activity. Among them, the ethyl acetate (EA) fraction showed the highest antioxidant activity. Then, EA fraction was selected for the purification of potential antioxidant compounds. The hepatoprotective effects of EA fraction and its most active constituent, gallic acid (GA), were evaluated against CCl4-induced hepatotoxicity in rats. CCl4 induced oxidative stress by a significant rise in serum marker enzymes. However, pretreatment of rats with EA fraction of fruits of L. inermis at a dose of 250 mg kg−1 body weight and GA significantly lowered some serum biochemical parameters (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase) in treated rats. A significant reduction in hepatic thiobarbituric acid reactive substances and an increase in antioxidant enzymes namely superoxide dismutase, catalase, and glutathione peroxidase by treatment with plant extract and GA, against CCl4-treated rats, were observed. Histopathological examinations showed extensive liver injuries, characterized by extensive hepatocellular necrosis, vacuolization, and inflammatory cell infiltration. This potential antioxidant activity is comparable to those of the major purified antioxidant compound, GA. Based on these results, it was observed that fruits of L. inermis protect liver from oxidative stress induced by CCl4 and thus help in evaluation of traditional claim on this plant.

Inhibition of pancreatic lipase, α-glucosidase, α-amylase, and hypolipidemic effects of the total flavonoids from Nelumbo nucifera leaves

ETHNOPHARMACOLOGICAL RELEVANCE

Nelumbo nucifera Gaertn. leaves have been used as medicinal herbs in the past 1300 years, specifically utilized to cure hyperlipidemia, hyperglycemia, and obesity. It has been recorded in the most famous medicinal book in China for more than 400 years. The present study aims to identify the potential therapeutic activities of the flavonoids isolated from Nelumbo nucifera leaves.

MATERIALS AND METHODS

Nelumbo nucifera leaf flavonoids (NLF) were tested for the inhibition of lipase, α-glucosidase, and α-amylase activities in vitro. A single dose of NLF was administered by oral gavage in mice for acute toxicity. Wistar rats with high-fat diet-induced hyperlipidemia and two other animal models were used to evaluate the hypolipidemic effects of NLF.

RESULTS

Our in vitro biochemistry tests revealed that the NLF showed high inhibitory activity against porcine pancreatic lipase, α-amylase, and α-glucosidase with IC50 values of 0.38 ± 0.022, 2.20 ± 0.18, and 1.86 ± 0.018 mg/mL, respectively. Furthermore, the NLF significantly lowered the lipid components, such as the total cholesterol, triglycerides, low-density lipoprotein cholesterol, and malondialdehyde, in various established in vivo systems and raised the high-density lipoprotein cholesterol. Moreover, the NLF alleviated high-fat diet-induced lipid accumulation in the liver.

CONCLUSIONS

The results demonstrate that NLFs can effectively ameliorate hyperlipidemia and inhibit the key enzymes related to type 2 diabetes mellitus. Our findings may provide new pharmacological basis for the treatment of hyperlipidemia, hyperglycemia, and obesity using NLFs.

Protective effects of alkaloid compounds from Nelumbinis Plumula on tert-butyl hydroperoxide-induced oxidative stress

This study was conducted to investigate the effect of Nelumbinis Plumula total alkaloid (NPA) and its main alkaloid components on oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in the human hepatocellular HepG2 cell line. According to HPLC analysis, several major alkaloid compounds such as liensinine, isoliensinine and neferine were present in NPA. The cytotoxic effects in 0.55 mM t-BHP-induced HepG2 cells were significantly inhibited by NPA and the major compound in NPA, neferine, showed the strongest activities. The protective effect of neferine against oxidative stress induced by t-BHP may be associated with decreased ROS formation, TBARS generation, LDH release and increased GSH levels, suggesting their involvement of the cytoprotective on oxidative stress. The effects were comparable with quercetin, which was used as positive control. Overall, total alkaloid and alkaloid compounds from Nelumbinis Plumula displayed a significant cytoprotective effect against oxidative stress. Further study is needed to elucidate the relationship between the chemical structures of the components in NPA and their protective effect on oxidative stress.

In vitro and in vivo hepatoprotective and antioxidant activity of ethanolic extract from Meconopsis integrifolia (Maxim.) Franch

ETHNOPHARMACOLOGICAL RELEVANCE

Meconopsis integrifolia (Maxim.) Franch is a high mountain endemic species used as a traditional Tibetan and Mongolian herb to treat hepatitis, pneumonia, and edema. This study aims to investigate the hepatoprotective and antioxidant effects of Meconopsis integrifolia ethanolic extract (MIE) in vitro and in vivo.

MATERIALS AND METHODS

The in vitro antioxidant property of MIE was investigated by employing various established systems. Rats with carbon tetrachloride (CCl4)-induced liver injury were used to assess the hepatoprotective and antioxidant effect of MIE in vivo. The level or activity of alkaline phosphatase (ALP), glutamate pyruvate transaminase (ALT), aspartate aminotransferase (AST), and total bilirubin (TB) in the blood serum and thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) in the liver and kidney of the rats were assayed using standard procedures.

RESULTS

MIE exhibited strong antioxidant ability in vitro. In the rats with CCl4-induced liver injury, the groups treated with MIE and silymarin showed significantly lower levels of ALT, AST, ALP, and TB. MIE demonstrated good antioxidant activities in both the liver and kidney of the rats in vivo.

CONCLUSIONS

MIE exhibits excellent hepatoprotective effects and antioxidant activities in vitro and in vivo, supporting the traditional use of Meconopsis integrifolia in the treatment of hepatitis.

Nuciferine prevents hepatic steatosis and injury induced by a high-fat diet in hamsters

Background

Nuciferine is a major active aporphine alkaloid from the leaves of N. nucifera Gaertn that possesses anti-hyperlipidemia, anti-hypotensive, anti-arrhythmic, and insulin secretagogue activities. However, it is currently unknown whether nuciferine can benefit hepatic lipid metabolism.

Methodology/Principal Findings

In the current study, male golden hamsters were randomly divided into four groups fed a normal diet, a high-fat diet (HFD), or a HFD supplemented with nuciferine (10 and 15 mg/kg·BW/day). After 8 weeks of intervention, HFD-induced increases in liver and visceral adipose tissue weight, dyslipidemia, liver steatosis, and mild necroinflammation in hamsters were analyzed. Nuciferine supplementation protected against HFD-induced changes, alleviated necroinflammation, and reversed serum markers of metabolic syndrome in hamsters fed a HFD. RT-PCR and western blot analyses revealed that hamsters fed a HFD had up-regulated levels of genes related to lipogenesis, increased free fatty acid infiltration, and down-regulated genes involved in lipolysis and very low density lipoprotein secretion. In addition, gene expression of cytochrome P4502E1 and tumor necrosis factor-α were also increased in the HFD group. Nuciferine supplementation clearly suppressed HFD-induced alterations in the expression of genes involved in lipid metabolism.

Conclusions/Significance

Nuciferine supplementation ameliorated HFD-induced dyslipidemia as well as liver steatosis and injury. The beneficial effects of nuciferine were associated with altered expression of hepatic genes involved in lipid metabolism.

Protective effects of Keemun black tea polysaccharides on acute carbon tetrachloride-caused oxidative hepatotoxicity in mice

This study was designed to investigate chemical characterization of the water-soluble polysaccharides extracted from Keemun black tea (KBTP), and their antioxidant and hepatoprotective effects against CCl4-induced oxidative damage in mice. HPLC analysis revealed that KBTP is the typical acidic heteropolysaccharides and consisted of nine monosaccharides. Furthermore, KBTP showed highly ferric-reducing antioxidant power and scavenging effects against DPPH, OH and O2(-) in vitro. Administration of KBTP (200, 400 and 800 mg/kg bw) in mice ahead of CCl4 injection could observably antagonize the CCl4-induced increases in serum ALT, AST, TG and TC, and the hepatic MDA and 8-iso-PGF2a levels, respectively. Mice with KBTP pretreatment displayed a better profile of hepatosomatic index and the improved GSH and SOD activities in comparison with CCl4-intoxicated mice. These biochemical results were further supported with liver histopathological assessment, revealing that KBTP has an observable prevention of liver damage induced by CCl4 in mice.

Hepatoprotection by chemical constituents of the marine brown alga Spatoglossum variabile: a relation to free radical scavenging potential

CONTEXT

In the course of searching hepatoprotective agents from natural sources, the protective effect of chemical constituents of the marine brown alga Spatoglossum variabile Figaro et DE Notar (Dictyoaceae) against CCl₄-induced liver damage in Wistar rats was investigated. The compounds were first investigated for in vitro radical scavenging potential and were also tested for β-glucuronidase inhibition to further explore the relationship between hepatoprotection and antiradical potential.

METHODS

The compounds cinnamic acid esters 1 and 2 and aurone derivatives 3 and 4 were first investigated for in vitro radical scavenging potential against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH), and superoxide anion radicals. In vivo hepatoprotective studies were performed in seven groups (n = 6) of Wistar rats. The test groups were pretreated with compounds (10 mg/kg body weight, po) orally for 30 min before the intraperitoneal administration of a dose of 20% CCl₄ diluted with dietary cooking oil. Moreover, compounds were also tested for β-glucuronidase inhibition to explore the relationship between hepatoprotection and radical scavenging potential.

RESULTS

The test compounds 1-4 were found to exhibit antiradical activity against 1,1-diphenyl-2-picrylhydrazyl radicals with IC₅₀ values ranging between 54 and 138 µM, whereas aurone derivatives 3 and 4 additionally exhibited superoxide anion scavenging effects with IC₅₀ values of 95 and 87 µM, respectively. In addition, these compounds were found to be weak inhibitors of xanthine oxidase (IC₅₀ ≥1000 µM). In animal model, pretreatment with compounds 2-4 significantly blocked the CCl₄-induced increase in the levels of the serum biochemical markers.

CONCLUSION

It appears that the hepatoprotection afforded by these compounds was mainly due to their radical scavenging activity that protected the cells from the free radicals generated by CCl₄-induced hepatotoxicity.

Moringa oleifera hydroethanolic extracts effectively alleviate acetaminophen-induced hepatotoxicity in experimental rats through their antioxidant nature

The aim of the study was to investigate the in vitro antioxidant properties Moringa oleifera Lam. (MO) extracts and its curative role in acetaminophen (APAP)- induced toxic liver injury in rats caused by oxidative damage. The total phenolic content and antioxidant properties of hydroethanolic extracts of different MO edible parts were investigated by employing an established in vitro biological assay. In the antihepatotoxic study, either flowers or leaves extract (200 mg/kg or 400 mg/kg, i.p) were administered an hour after APAP administration, respectively. N-Acetylcysteine was used as the positive control against APAP-induced hepatotoxicity. The levels of liver markers such as alanine aminotransferase (ALT) and the levels of oxidative damage markers including malondialdehyde (MDA), 4-hydroxynonenal (4-HNE) protein adduct, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were analysed and compared between experimental groups. Among MO edible parts the flower extracts contain the highest total phenolic content and antioxidant capacity, followed by leaves extract. The oxidative marker MDA, as well as 4-HNE protein adduct levels were elevated and GSH, SOD and CAT were significantly decreased in groups treated with hepatotoxin. The biochemical liver tissue oxidative markers measured in the rats treated with MO flowers and leaves hydroethanolic extracts showed a significant (p < 0.05) reduction in the severity of the liver damage. The results of this study strongly indicate the therapeutic properties of MO hydroethanolic extracts against acute liver injury and thereby scientifically support its traditional use.

Screening and determination for potential α-glucosidase inhibitors from leaves of Acanthopanax senticosus harms by using UF-LC/MS and ESI-MS(n)

INTRODUCTION

Acanthopanax senticosus Harms is a typical Chinese herb with flavonoids existing in all parts of the plant but with the largest content in leaves. However, leaves have been neglected in past research. To investigate the potential use of leaves of A. senticosus Harms for discovering lead compounds to treat type 2 diabetes, the herb leaves were selected for screening the potential of α-glucosidase inhibitors.

OBJECTIVE

To screen for candidates of α-glucosidase inhibitors from leaves of A. senticosus Harms and evaluate the structure-activity relationship of the α-glucosidase inhibitors.

METHODOLOGY

Ultrafiltration liquid chromatography/mass spectrometry (UF-LC/MS) assay was developed for screening candidates of α-glucosidase inhibitors from leaves of A. senticosus Harms. The interesting compounds were identified by using reversed-phase high performance liquid chromatography with diode array detector and electrospray ionisation multiple-stage tandem mass spectrometry (RP-HPLC-DAD-ESI-MS(n) ), and confirmed by using electrospray ionisation Fourier transform ion cyclotron resonance multiple-stage tandem mass spectrometry (ESI-FT-ICR-MS(n)). Furthermore, the α-glucosidase inhibitory activity of the compounds detected was estimated using in vitro assays.

RESULTS

Eight compounds that might bind to α-glucosidase were screened and seven of them were identified successfully. The α-glucosidase inhibitory activity of the related compounds in leaves of A. senticosus Harms was determined.

CONCLUSION

The results obtained provided new information for the discovery of potential α-glucosidase inhibitors and the potential anti-diabetic application of the leaves of A. senticosus Harms.

Antioxidant activities of extract and fractions from receptaculum nelumbinis and related flavonol glycosides

The antioxidant activities of ethanolic crude extract (ECE) and its four different solvent sub-fractions (namely, petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n-butanol fraction (BF) and the aqueous fraction (AF) from the receptacles of Nelumbo nucifera Gaertn. (Receptaculum Nelumbinis) were investigated using two in vitro antioxidant assays. BF showed the highest total phenolic content (607.6 mg/g gallic acid equivalents), total flavonoid content (862.7 mg/g rutin equivalents) and total proanthocyanidin content (331.0 mg/g catechin equivalents), accompanied with the highest antioxidant activity compared to other fractions through 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. Five flavonol glycosides, namely hyperoside (1), isoquercitrin (2), quercetin-3-O-β-d-glucuronide (3), isorhamnetin-3-O-β-d-galactoside (4) and syringetin-3-O-β-d-glucoside (5) were isolated from the Receptaculum Nelumbinis. Compounds 2-5 were isolated for the first time from the Receptaculum Nelumbinis. The five isolated flavone glycosides, particularly compounds 1-3, demonstrated significant DPPH and ABTS radical scavenging activity, with IC(50) values of 8.9 ± 0.2, 5.2 ± 0.2, 7.5 ± 0.1 for DPPH and 114.2 ± 1.7, 112.8 ± 0.8, 172.5 ± 0.7 μg/mL for ABTS, respectively. These results suggest that Receptaculum Nelumbinis has strong antioxidant potential and may be potentially used as a safe and inexpensive bioactive source of natural antioxidants.

In vitro and in vivo antioxidant activity of the ethanolic extract from Meconopsis quintuplinervia

AIMS OF THE STUDY

Meconopsis quintuplinervia, a medicinal herb endemic to the Tibetan region, is used to treat hepatitis. The aim of this study is to evaluate the antioxidant potential of the ethanolic extract of this herb using different assays.

MATERIALS AND METHODS

The antioxidant capacity of Meconopsis quintuplinervia was investigated using various established in vitro systems. An in vivo study of carbon tetrachloride (CCl(4))-induced antioxidant activity in mice was also conducted by examining the levels of malondialdehyde (MDA) and the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH).

RESULTS

The extract showed strong in vitro antioxidant ability. In the in vivo study, CCl(4)-induced oxidative stress caused significant decreases in the SOD, CAT, and GSH levels and a significant increase in the MDA level, most of which were significantly reversed (except for SOD in the liver.) by treatment with the extract and standard Vitamin E.

CONCLUSION

This study clearly indicates that the ethanolic extract of Meconopsis quintuplinervia is a valuable source of natural antioxidants. These findings provide scientific support for the traditional use of this herb as a Tibetan medicine for liver diseases.

Astragalin from Cassia alata induces DNA adducts in vitro and repairable DNA damage in the yeast Saccharomyces cerevisiae

Reverse phase-solid phase extraction from Cassia alata leaves (CaRP) was used to obtain a refined extract. Higher than wild-type sensitivity to CaRP was exhibited by 16 haploid Saccharomyces cerevisiae mutants with defects in DNA repair and membrane transport. CaRP had a strong DPPH free radical scavenging activity with an IC₅₀ value of 2.27 μg mL⁻¹ and showed no pro-oxidant activity in yeast. CaRP compounds were separated by HPLC and the three major components were shown to bind to DNA in vitro. The major HPLC peak was identified as kampferol-3-O-β-d-glucoside (astragalin), which showed high affinity to DNA as seen by HPLC-UV measurement after using centrifugal ultrafiltration of astragalin-DNA mixtures. Astragalin-DNA interaction was further studied by spectroscopic methods and its interaction with DNA was evaluated using solid-state FTIR. These and computational (in silico) docking studies revealed that astragalin-DNA binding occurs through interaction with G-C base pairs, possibly by intercalation stabilized by H-bond formation.

Hepatoprotective potential of Clitoria ternatea leaf extract against paracetamol induced damage in mice

Background and Aim: Clitoria ternatea, a medicinal herb native to tropical equatorial Asia, is commonly used in folk medicine to treat various diseases. The aim of the present study is to evaluate the hepatoprotective and antioxidant activity of C. ternatea against experimentally induced liver injury. Methods: The antioxidant property of methanolic extract (ME) of C. ternatea leaf was investigated by employing an established in vitro antioxidant assay. The hepatoprotective effect against paracetamol-induced liver toxicity in mice of ME of C. ternatea leaf was also studied. Activity was measured by monitoring the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and billirubin along with histopathological analysis. Results: The amount of total phenolics and flavonoids were estimated to be 358.99 ± 6.21 mg/g gallic acid equivalent and 123.75 ± 2.84 mg/g catechin equivalent, respectively. The antioxidant activity of C. ternatea leaf extract was 67.85% at a concentration of 1 mg/mL and was also concentration dependant, with an IC₅₀ value of 420.00 µg/mL. The results of the paracetamol-induced liver toxicity experiments showed that mice treated with the ME of C. ternatea leaf (200 mg/kg) showed a significant decrease in ALT, AST, and bilirubin levels, which were all elevated in the paracetamol group (p < 0.01). C. ternatea leaf extract therapy also protective effects against histopathological alterations. Histological studies supported the biochemical findings and a maximum improvement in the histoarchitecture was seen. Conclusions: The current study confirmed the hepatoprotective effect of C. ternatea leaf extract against the model hepatotoxicant paracetamol. The hepatoprotective action is likely related to its potent antioxidative activity.