Hepatoprotective activity of petroleum ether, diethyl ether, and methanol extract of Scoparia dulcis L. against CCl4-induced acute liver injury in mice

Objectives:

The present study was aimed at assessing the hepatoprotective activity of 1:1:1 petroleum ether, diethyl ether, and methanol (PDM) extract of Scoparia dulcis L. against carbon tetrachloride-induced acute liver injury in mice.

Materials and Methods:

The PDM extract (50, 200, and 800 mg/kg, p.o.) and standard, silymarin (100 mg/kg, p.o) were tested for their antihepatotoxic activity against CCl4-induced acute liver injury in mice. The hepatoprotective activity was evaluated by measuring aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total proteins in serum, glycogen, lipid peroxides, superoxide dismutase, and glutathione reductase levels in liver homogenate and by histopathological analysis of the liver tissue. In addition, the extract was also evaluated for its in vitro antioxidant activity using 1, 1-Diphenyl-2-picrylhydrazyl scavenging assay.

Results:

The extract at the dose of 800 mg/kg, p.o., significantly prevented CCl4-induced changes in the serum and liver biochemistry (P < 0.05) and changes in liver histopathology. The above results are comparable to standard, silymarin (100 mg/kg, p.o.). In the in vitro 1, 1-diphenyl-2-picrylhydrazyl scavenging assay, the extract showed good free radical scavenging potential (IC 50 38.9 ± 1.0 μg/ml).

Conclusions:

The results of the study indicate that the PDM extract of Scoparia dulcis L. possesses potential hepatoprotective activity, which may be attributed to its free radical scavenging potential, due to the terpenoid constituents.     

Hepatoprotective and anti-inflammatory activities of Plantago major L

Objective:

The aim of this study was to investigate anti-inflammatory and hepatoprotective activities of Plantago major L. (PM).

Materials and Methods:

Anti-inflammatory activity: Control and reference groups were administered isotonic saline solution (ISS) and indomethacin, respectively. Plantago major groups were injected PM in doses of 5 mg/kg (PM-I), 10 mg/kg (PM-II), 20 mg/kg (PM-III) and 25 mg/kg (PM-IV). Before and three hours after the injections, the volume of right hind-paw of rats was measured using a plethysmometer.

Hepatoprotective Activity:

The hepatotoxicity was induced by carbon tetrachloride (CCl4) administration. Control, CCl4 and reference groups received isotonic saline solution, CCl4 and silibinin, respectively. Plantago major groups received CCl4 (0.8 ml/kg) and PM in doses of 10, 20 and 25 mg/kg, respectively for seven days. Blood samples and liver were collected on the 8th day after the animals were killed.

Results:

Plantago major had an anti-inflammatory effect matching to that of control group at doses of 20 and 25 mg/kg. It was found that reduction in the inflammation was 90.01% with indomethacin, 3.10% with PM-I, 41.56% with PM-II, 45.87% with PM-III and 49.76% with PM-IV. Median effective dose (ED50) value of PM was found to be 7.507 mg/kg. Plantago major (25 mg/kg) significantly reduced the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels when compared to the CCl4 group. The histopathological findings showed a significant difference between the PM (25 mg/kg) and CCl4 groups.

Conclusion:

The results showed that PM had a considerable anti-inflammatory and hepatoprotective activities.     

Evaluation of hepatoprotective activity of Cissus quadrangularis stem extract against isoniazid-induced liver damage in rats

Objective:

The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis (CQ) against isoniazid-induced hepatotoxicity in rats.

Materials and Methods:

The successive petroleum ether (60–80°C) and methanol extracts of C. quadrangularis were used. Hepatic damage was induced in Wistar rats by administering isoniazid (54 mg/kg, p.o.) once daily for 30 days. Simultaneously, CQ (500 mg/kg p.o) was administered 1 h prior to the administration of isoniazid (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) was used as a reference drug.

Results:

Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase, and bilirubin following isoniazid administration were significantly lowered due to pretreatment with CQ. Isoniazid administration significantly increased lipid peroxidation (LPO) and decreased antioxidant activities such as reduced glutathione, superoxide dismutase, and catalase. Pretreatment of rats with CQ significantly decreased LPO and increased the antioxidant activities.

Conclusion:

The results of this study indicated that the hepatoprotective effect of CQ might be attributed to its antioxidant property.     

Evaluation of the in vivo antimalarial activity of ethanolic leaf and stembark extracts of Anthocleista djalonensis

Objective:

To evaluate the in vivo antimalarial activities of ethanolic leaf and stembark extracts of Anthocleista djalonensis used traditionally as malarial remedy in Southern Nigeria in mice infected with Plasmodium berghei berghei.

Methods:

The ethanolic extracts of the A. djalonensis leaf (1000 – 3000 mg/kg/day) and stembark (220 – 660 mg/kg/day) were screened for blood schizonticidal activity against chloroquine-sensitive P. berghei in mice. The schizonticidal effect during early and established infections was investigated.

Results:

The A. djalonensis leaf extract (1000 – 3000 mg/kg/day) exhibited a significant antiplasmodial activity both in the 4-day early infection test and in the established infection with a considerable mean survival time, which was incomparable to that of the standard drug, chloroquine (5 mg/kg/day). The stembark extract (220 – 660 mg/kg/day) also demonstrated a promising blood schizontocidal activity in early and established infections.

Conclusion:

These plant extracts possess considerable antiplasmodial activities, which justify their use in ethnomedicine and can be exploited in malaria therapy.     

Protective effect of ethyl acetate fraction of Rhododendron arboreum flowers against carbon tetrachloride-induced hepatotoxicity in experimental models

Objective:

To evaluate the hepatoprotective potential of ethyl acetate fraction of Rhododendron arboreum (Family: Ericaceae) in Wistar rats against carbon tetrachloride (CCl₄)-induced liver damage in preventive and curative models.

Materials and Methods:

Fraction at a dose of 100, 200, and 400 mg/kg was administered orally once daily for 14 days in CCl₄-treated groups (II, III, IV, V and VI). The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), γ-glutamyltransferase (γ -GT), and bilirubin were estimated along with activities of glutathione S-transferase (GST), glutathione reductase, hepatic malondialdehyde formation, and glutathione content.

Result and Discussion:

The substantially elevated serum enzymatic activities of SGOT, SGPT, SALP, γ-GT, and bilirubin due to CCl₄ treatment were restored toward normal in a dose-dependent manner. Meanwhile, the decreased activities of GST and glutathione reductase were also restored toward normal. In addition, ethyl acetate fraction also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl₄-intoxicated rats in a dose-dependent manner. Silymarin used as standard reference also exhibited significant hepatoprotective activity on post-treatment against CCl₄-induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethyl acetate fraction has a potent hepatoprotective action against CCl₄-induced hepatic damage in rats.     

Hepatoprotective activity of aqueous extract of Portulaca oleracea in combination with lycopene in rats

Objective:

To investigate the hepatoprotective activity of the aqueous extract of the aerial parts of Portulaca oleracea (P. oleracea) in combination with lycopene against carbon tetrachloride induced hepatotoxicity in rats.

Materials and Methods:

Hepatotoxicity was induced in male Wistar rats by intraperitoneal injection of carbon tetrachloride (0.1 ml/kg b.w for 14 days). The aqueous extract of P. oleracea in combination with lycopene (50 mg/kg b.w) was administered to the experimental animals at two selected doses for 14 days. The hepatoprotective activity of the combination was evaluated by the liver function marker enzymes in the serum [aspartate transaminases (AST), alanine transaminases (ALT), alkaline phosphatase (Alk.P), total bilirubin (TB), total protein (TP) and total cholesterol (TC)], pentobarbitone induced sleeping time (PST) and histopathological studies of liver.

Results:

Both the treatment groups showed hepatoprotective effect against carbon tetrachloride induced hepatotoxicity by significantly restoring the levels of serum enzymes to normal which was comparable to that of silymarin group. Besides, the results obtained from PST and histopathological results also support the study.

Conclusions:

The oral administration of P. oleracea in combination with lycopene significantly ameliorates CCl₄ hepatotoxicity in rats.     

Anticlastogenic activity of flavonoid reach extract of Cassia auriculata Linn. on experimental animal

Objective:

To determine antimutagenic activity of Cassia auriculata Linn. on chromosomal damage induced by cyclophosphamide (CP).

Material and Methods:

In the present investigation, four groups of six Swiss albino mice in each group were used. Excepting for thefirst group all the remaining groups were treated with CP (50 mg/kg). Mice of third and fourth group were treated with ethyl acetate extract of C. auriculata Linn. at 100 mg/kg and 200 mg/kg with CP. Metaphase of bone marrow cells of all animals were analyzed for qualitative and quantitative chromosomal aberrations. Break, fragment, deletion, Polyploidy, pulverized, ring and total aberration were observed.

Results:

Flavonoids rich extracts of root of C. auriculata Linn. provided significant protection (P < 0.05) against CP induced chromosomal aberration. Total chromosomal aberration was found to be 12.16 and 7.33% in 100 and 200 mg/kg of extract treated animals respectively.

Conclusion:

From the present study it can was observed that ethyl acetate extract of C. auriculata Linn possess significant anti-mutagenic potential against CP induced chromosomal aberration.KEY WORDS: Bone marrow cells, Cassia auriculata Linn, cyclophosphamide     

Hepatoprotective activity of Leptadenia reticulata stems against carbon tetrachloride-induced hepatotoxicity in rats

Objective:

To evaluate the hepatoprotective activity of ethanolic and aqueous extract of stems of Leptadenia reticulata (Retz.) Wight. and Arn. in carbon tetrachloride (CCl₄)-induced hepatotoxicity in rats.

Materials and Methods:

The toxicant CCl₄ was used to induce hepatotoxicity at a dose of 1.25 ml/kg as 1 : 1 mixture with olive oil. Ethanolic and aqueous extracts of L. reticulata stems were administered in the doses of 250 and 500 mg/kg/day orally for 7 days. Silymarin (50 mg/kg) was used as standard drug. The hepatoprotective effect of these extracts was evaluated by the assessment of biochemical parameters such as serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, total bilirubin, serum protein, and histopathological studies of the liver.

Results:

Treatment of animals with ethanolic and aqueous extracts significantly reduced the liver damage and the symptoms of liver injury by restoration of architecture of liver as indicated by lower levels of serum bilirubin and protein as compared with the normal and silymarin-treated groups. Histology of the liver sections confirmed that the extracts prevented hepatic damage induced by CCl₄ showing the presence of normal hepatic cords, absence of necrosis, and fatty infiltration.

Conclusion:

The ethanolic and aqueous extracts of stems of L. reticulata showed significant hepatoprotective activity. The ethanolic extract is more potent in hepatoprotection in CCl₄-indiced liver injury model as compared with aqueous extract.     

In vitro antioxidant activity of pet ether extract of black pepper

Objective:

To investigate the in vitro antioxidant activity of different fractions (R1, R2 and R3) obtained from pet ether extract of black pepper fruits (Piper nigrum Linn.)

Materials and Methods:

The fractions R1, R2 and R3 were eluted from pet ether and ethyl acetate in the ratio of 6:4, 5:5 and 4:6, respectively.1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract.

Results:

The free radical scavenging activity of the different fractions of pet ether extract of P. nigrum (PEPN) increased in a concentration dependent manner. The R3 and R2 fraction of PEPN in 500 µg/ml inhibited the peroxidation of a linoleic acid emulsion by 60.48±3.33% and 58.89±2.51%, respectively. In DPPH free radical scavenging assay, the activity of R3 and R2 were found to be almost similar. The R3 (100µg/ml) fraction of PEPN inhibited 55.68±4.48% nitric oxide radicals generated from sodium nitroprusside, whereas curcumin in the same concentration inhibited 84.27±4.12%. Moreover, PEPN scavenged the superoxide radical generated by the Xanthine/Xanthine oxidase system. The fraction R2 and R3 in the doses of 1000µg/ml inhibited 61.04±5.11% and 63.56±4.17%, respectively. The hydroxyl radical was generated by Fenton''s reaction. The amounts of total phenolic compounds were determined and 56.98 µg pyrocatechol phenol equivalents were detected in one mg of R3.

Conclusions:

P. nigrum could be considered as a potential source of natural antioxidant.     

14-Deoxyandrographolide desensitizes hepatocytes to tumour necrosis factor-alpha-induced apoptosis through calcium-dependent tumour necrosis factor receptor superfamily member 1A release via the NO/cGMP pathway

BACKGROUND AND PURPOSE

Andrographis paniculata (AP) has been found to display hepatoprotective effect, although the mechanism of action of the active compounds of AP in this context still remains unclear. Here, we evaluated the hepatoprotective efficacy of 14-deoxyandrographolide (14-DAG), a bioactive compound of AP, particularly its role in desensitization of hepatocytes to tumour necrosis factor-alpha (TNF-α)-induced signalling of apoptosis.

EXPERIMENTAL APPROACH

TNF-α-mediated ligand receptor interaction in hepatocytes in the presence of 14-DAG was studied in vitro in primary hepatocyte cultures, with the help of co-immunoprecipitation, confocal microscopy and FACS analysis. Events associated with 14-DAG-induced TNFRSF1A release from hepatocytes were determined using immunoblotting, biochemical assay and fluorimetric studies. Pulse-chase experiments with radiolabelled TNF-α and detection of apoptotic nuclei by terminal transferase-mediated dUTP nick-end labelling were performed under in vivo conditions.

KEY RESULTS

14-DAG down-regulated the formation of death-inducing signalling complex, resulting in desensitization of hepatocytes to TNF-α-induced apoptosis. Pretreatment of hepatocytes with 14-DAG accentuated microsomal Ca-ATPase activity through induction of NO/cGMP pathway. This resulted in enhanced calcium influx into microsomal lumen with the formation of TNFRSF1A–ARTS-1–NUCB2 complex in cellular vesicles. It was followed by the release of full-length 55 kDa TNFRSF1A and a reduction in the number of cell surface TNFRSF1A, which eventually caused diminution of TNF-α signal in hepatocytes.

CONCLUSION AND IMPLICATION

Taken together, the results demonstrate for the first time that 14-DAG desensitizes hepatocytes to TNF-α-mediated apoptosis through the release of TNFRSF1A. This can be used as a strategy against cytokine-mediated hepatocyte apoptosis in liver dysfunctions.     

Antipyretic and antibacterial activity of Chloranthus erectus (Buch.-Ham.) Verdcourt leaf extract: A popular folk medicine of Arunachal Pradesh

Objective:

The main objective of this work was to study the antipyretic and antibacterial activity of C. erectus (Buch.-Ham.) Verdcourt leaf extract in an experimental albino rat model.

Materials and Methods:

The methanol extract of C. erectus leaf (MECEL) was evaluated for its antipyretic potential on normal body temperature and Brewer’s yeast-induced pyrexia in albino rat’s model. While the antibacterial activity of MECEL against five Gram (−) and three Gram (+) bacterial strains and antimycotic activity was investigated against four fungi using agar disk diffusion and microdilution methods.

Result

Yeast suspension (10 mL/kg b.w.) elevated rectal temperature after 19 h of subcutaneous injection. Oral administration of MECEL at 100 and 200 mg/kg b.w. showed significant reduction of normal rectal body temperature and yeast-provoked elevated temperature (38.8 ± 0.2 and 37.6 ± 0.4, respectively, at 2–3 h) in a dose-dependent manner, and the effect was comparable to that of the standard antipyretic drug–paracetamol (150 mg/kg b.w.). MECEL at 2 mg/disk showed broad spectrum of growth inhibition activity against both groups of bacteria. However, MECEL was not effective against the yeast strains tested in this study.

Conclusion

This study revealed that the methanol extract of C. erectus exhibited significant antipyretic activity in the tested models and antibacterial activity as well, and may provide the scientific rationale for its popular use as antipyretic agent in Khamptis’s folk medicines.     

Role of serotonergic mechanism in gastric contractions induced by Indian Red Scorpion (Mesobuthus tamulus) venom

Aim:

Gastric dysfunctions are commonly seen after scorpion envenomation, and the underlying mechanisms are not clear. Therefore, the present study was undertaken to investigate the effect of Indian red scorpion (Mesobuthus tamulus, MBT) venom on gastric fundus muscle contraction and the underlying mechanisms involved.

Materials and Methods:

In vitro isometric contraction was recorded from gastric fundus muscle strips on a chart recorder. The tissue was exposed to different concentrations of serotonin or crude MBT venom. The contractile responses to venom were expressed as the percentage of maximum contraction produced by serotonin at the beginning of each experiment. The contractile responses to 1.0 μg/ml of crude MBT venom were ascertained in the absence or presence of serotonin antagonist, methysergide.

Results:

Serotonin produced concentration-dependent fundus contractions (0.004–4.0 μM), and maximum contractile response was observed at 4.0 μM of serotonin. Hence, the contractile response obtained at 4.0 μM of serotonin was taken for normalization. The crude MBT venom (0.1–1.0 μg/ml) produced a concentration-dependent increase in fundus contractions (as % of maximum fundus contraction produced by serotonin at 4.0 μM). The maximum response was observed at 1.0 μg/ml of crude venom and a further increase in the concentration, up to 3.0 μg/ml, did not increase the response. In a separate series of experiments, pre-treatment with methysergide (1.0 μM) significantly attenuated the contractile response elicited by the venom (1.0 μg/ml) (P<0.05) and blocked the serotonin (4.0 μM) response.

Conclusion:

The results suggest that the crude MBT venom produces gastric fundus contractions by partially involving serotonin.     

In vivo antimalarial activity of ethanolic leaf extract of Stachytarpheta cayennensis

Objective:

To evaluate the in vivo antiplasmodial activity of the ethanol leaf extract of Stachytarpheta cayennensis in the treatment of various ailment in Niger Delta region of Nigeria, in Plasmodium berghei infected mice.

Materials and Methods:

The ethanolic leaf extract of Stachytarpheta cayennensis (90-270 mg/kg/day) was screened for blood schizonticidal activity against chloroquine sensitive Plasmodium berghei berghei in mice. The schizonticidal effect during early and established infections was investigated.

Result:

Stachytarpheta cayennensis (90-270 mg/kg/day) exhibited significant (P< 0.05) blood schizonticidal activity both in 4-day early infection test and in established infection with a considerable mean survival time comparable to that of the standard drug, chloroquine, 5 mg/kg/day.

Conclusion:

The leaf extract possesses significant (P< 0.05) antiplasmodial activity which confirms it''s use in folkloric medicine in the treatment of malaria.     

Hypoglycemic effect of aqueous extract of Parthenium hysterophorus L. in normal and alloxan induced diabetic rats

Objectives:

To study the effects of Parthenium hysterophorus L. flower on serum glucose level in normal and alloxan induced diabetic rats.

Materials and Methods:

Albino rats were divided into six groups of six animals each, three groups of normal animals receiving different treatments consisting of vehicle, aqueous extract of Parthenium hysterophorus L. flower (100 mg/kg) and the standard antidiabetic drug, glibenclamide (0.5 mg/kg). The same treatment was given to the other three groups comprising alloxan induced diabetic animals. Fasting blood glucose level was estimated using the glucose oxidase method in normal and alloxan induced diabetic rats, before and 2 h after the administration of drugs.

Results:

Parthenium hysterophorus L. showed significant reduction in blood glucose level in the diabetic (P<0.01) rats. However, the reduction in blood glucose level with aqueous extract was less than with the standard drug glibenclamide. The extract showed less hypoglycemic effect in fasted normal rats, (P<0.05).

Conclusion:

The study reveals that the active fraction of Parthenium hysterophorus L. flower extract is very promising for developing standardized phytomedicine for diabetes mellitus.     

Immunosuppressive properties of Pluchea lanceolata leaves

Objective:

To investigate the immunosuppressive potential of Pluchea lanceolata 50% ethanolic extract (PL) and its bioactive chloroform fraction (PLC).

Materials and Methods:

Preliminary screening of the Pluchea lanceolata 50% ethanolic extract (PL) was carried out with basic models of immunomodulation, such as, the humoral antibody response (hemagglutination antibody titers), cell-mediated immune response (delayed-type hypersensitivity), skin allograft rejection test, in vitro (C. albicans method), and in vivo phagocytosis (carbon clearance test).The extract was then fractionated with chloroform, n-butanol, and water to receive the respective fractions by partitioning. These fractions were employed for flow cytometry to study the T-cell specific immunosuppressive potential of these fractions.

Results:

Oral administration of PL at doses of 50 to 800 mg/kg in mice, with sheep red blood cells (SRBC) as an antigen, inhibited both humoral and cell-mediated immune responses, as evidenced by the production of the circulating antibody titer and delayed-type hypersensitiviy reaction results, respectively, and the immune suppression was statistically significant (P < 0.01) in Balb/C mice. PL also decreased the process of phagocytosis both in vitro (31.23%) and ex vivo (32.81%) and delayed the graft rejection time (30.76%). To study the T-cell-specific activities, chloroform, n-butanol, and water fractions from P. lanceolata were tested for T-cell specific immunosuppressive evaluation, wherein only the chloroform fraction (PLC) showed significant (P < 0.01) suppression of CD8+ / CD4+ T-cell surface markers and intracellular Th1 (IL-2 and IFN-_Y) cytokines at 25 – 200 mg/kg p.o. doses. PLC, however, did not show significant suppression of the Th2 (IL-4) cytokine.

Conclusion:

The findings from the present investigation reveal that P. lanceolata causes immunosuppression by inhibiting Th1 cytokines.     

Fertility, developmental toxicity and teratogenicity in albino rats treated with methanol sub-fraction of Carica papaya seeds

Objective:

To evaluate the status of fertility, developmental stages during gestation and teratological changes, if any, following oral administration of methanol sub-fraction (MSF) of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in rats.

Materials and Methods:

The MSF was administered at the doses of 50 mg contraceptive dose (CD), 100 mg (2× CD), 250 mg (5× CD) and 500 mg (10× CD)/kg body wt/day along with vehicle-treated control using 10 male and 20 female Wistar rats in each group. Necropsies were performed one day before the expected parturition. Status of gravid/non-gravid uterus, the number of corpora lutea in the ovary, implantation status, fetal wellbeing, fetal resorption, fetal body weight, external, visceral and skeletal malformations were recorded.

Results:

Pregnancies were recorded in vehicle-treated control animals and in the animals treated with 50 mg/kg body wt/day. The animals treated with 2× CD, 5× CD and 10× CD did not get pregnant. The fetuses and the status of the ovary, uterus and implantation, fetal body weight, soft tissues and skeletal structures were recorded normal. Data were comparable to those of control.

Conclusion:

The results suggest that the test substance had no developmental toxicity and teratogenicity which could affect pregnancy, implantation and gestation.     

Bicyclol protects HepG2 cells against D-galacto-samine-induced apoptosis through inducing heat shock protein 27 and mitochondria associated pathway

Aim:

To study the inducing effect of bicyclol on heat shock protein 27 (HSP27) and its role on anti-apoptosis in HepG2 cells intoxicated with D-galactosamine (D-GaIN).

Methods:

HepG2 cells were treated with various concentrations of bicyclol and then subjected to D-GaIN intoxication. Apoptosis was assayed by hoechst 33258 staining and flow cytometry analysis. HSP27, cytochrome c, apoptosis inducing factor (AIF) and c-Jun N-terminal kinase (JNK) were assayed by Western blot. Heat shock factor 1 (HSF1) was determined by electrophoretic mobility shift assay and the interactions of HSP27 with cytochrome c and AIF were detected by co-immunoprecipitation.

Results:

The results showed that bicyclol induced HSP27 protein and mRNA expression in HepG2 cells in both time- and dose-dependent manners (the maximal response: 1.23 fold increase at 100 μmol/L). Bicyclol treatment stimulated HSF1 activation and increased the HSF1-HSE binding activity (the maximal response: 2.1 fold increase at 100 μmol/L). This inducing effect of bicyclol on HSP27 and HSF1 was markedly blocked by quercetin. Pretreatment of the cells with bicyclol markedly attenuated D-GaIN-induced apoptosis and the release of cytochrome c and AIF from mitochondria. The induced HSP27 by bicyclol suppressed the activity of caspase-3 and the phosphorylation of JNK caused by D-GaIN in HepG2 cells. All the above effect of bicyclol against D-GaIN-induced hepatocytes apoptosis were significantly reversed by quercetin.

Conclusion:

HSP27 is involved in the anti-hepatocytes apoptosis of bicyclol, and this effect of bicyclol-induced HSP27 is mainly through inhibition of mitochondria and JNK apoptotic pathways.     

Antimicrobial clerodane diterpenoids from Microglossa angolensis Oliv. et Hiern

Objective:

To identify the antimicrobial components present in Microglossa angolensis following fractionation of the methylene chloride extract of the aerial part of this plant.

Materials and Methods:

The plant was dried and extracted by percolation with methylene chloride. The dry extract was fractionated and purified by silica gel column chromatography. The isolated compounds were identified by comparison of their Nuclear Magnetic Resonance (NMR) spectral data with those reported in the literature. Antimicrobial activity was assayed by broth macro dilution method.

Results:

The crude extract of M. angolensis displayed significant antifungal and antibacterial activities (MIC = 312.50-1250μg/ml). 6β-(2-methylbut-2(Z)-enoyl)-3α,4α,15,16-bis-epoxy-8β,10βH-ent-cleroda-13(16),14-dien-20,12-olide and spinasterol were the most active compounds (MIC = 1.56-100μg/ml) and the most sensitive microorganisms were Enterococcus faecalis and Candida tropicalis for bacteria and yeasts respectively.

Conclusion:

The isolation of these active antibacterial and antifungal principles supports the use of M. angolensis in traditional medicine for the treatment of gastro-intestinal disorders.     

Preliminary isolation and in vitro antiyeast activity of active fraction from crude extract of Gracilaria changii

Objective:

To isolate the active fraction from crude extract of Gracilaria changii and to determine its in vitro antifungal activity.

Materials and Methods:

The active fraction was isolated from the crude extract of G. changii by various purification procedures such as column chromatography, thin layer chromatography, bioauthograph etc. The in vitro antifungal activity (Candida albicans) of the active fraction (1.00, 0.50, and 0.25 mg/ml) was studied by disc diffusion method and the effect of the active fraction on the morphology of yeast was done by scanning electron microscope (SEM) studies.

Results:

An active fraction with remarkable antifungal activity was separated from the crude extract. The active fraction was effective as a fungicide against C. albicans and showed a dose-dependent antifungal activity. A Scanning Electron Microscope (SEM) study confirmed the fungicidal effect of G. changii active fraction on C. albicans, by changing the normal morphology of C. albicans.

Conclusion:

From G. changii crude extract, an active fraction with remarkable in vitro antifungal activity has been isolated.     

Nimesulide inhibits the proliferation of HepG2 by up-regulation of Smad4

Objectives:

Hepatocellular carcinoma (HCC) is receiving increased attention. This study was designed to investigate the effect of selective Cyclooxygenase-2 (COX-2) inhibitor, nimesulide, on the expression of Smad4 in human hepatocellular carcinoma HepG2.

Materials and Methods:

HepG2 cells were incubated in various concentrations of nimesulide (25, 50, 100, 200, 400 μmol/L) to detect the effect of proliferation by MTS. The apoptosis of HepG2 was determined by TUNEL; fluorescence microscope was used to observe the expression of Smad4.

Results:

The result showed that nimesulide inhibited the proliferation of HepG2 cell in a concentrations-dependent manner, and promoted the karyopyknosis and fragmentation of HepG2 cell nucleus, induced its apoptosis, the number of fluorescence labeling of Smad4 in Nimesulide group was higher than control group (P<0.05).

Conclusions:

Nimesulide inhibits the proliferation and promotes apoptosis of HepG2 by up-regulation of Smad4 in HepG2.KEY WORDS: Hepatic carcinoma cell, Nimesulide, Smad4