Guiera senegalensis J.F. Gmel is a broad-spectrum African folk- medicinal plant, having activities against fowlpox and herpes viruses. Very recently, we have shown the anti-hepatitis B vius (HBV) potential of G. senegalensis leaves extract (GSLE). Here, we report the antioxidative and hepatoprotective efficacy of GSLE, including HPTLC quantification of four biomarkers of known antioxidative and antiviral activities. In cultured liver cells (HuH7) GSLE attenuated DCFH-induced oxidative stress and cytotoxicity. This was supported by in vitro DPPH radical-scavenging and β-carotene-linoleic acid bleaching assays that showed strong antioxidant activity of GSLE. Further, two simple and sensitive HPTLC methods (I and II) were developed and validated to quantify β-amyrin, β- sitosterol, lupeol, ursolic acid in GSLE. While HPTLC-I (hexane: ethylacetate; 75:25; v/v) enabled quantification of β-amyrin (Rf = 0.39; 20.64 μg/mg) and β-sitosterol (Rf = 0.25; 18.56 μg/mg), HPTLC-II (chloroform: methanol; 97:3; v/v) allowed estimation of lupeol (Rf = 0.47; 6.72 μg/mg) and ursolic acid (Rf = 0.23; 5.81 μg/mg) in GSLE. Taken together, the identified biomarkers strongly supported the antioxidant and anti-HBV potential of GSLE, suggesting its activity via abating the oxidative stress. To our knowledge, this is the first report on HPTLC analysis of these biomarkers in G. senegalensis that could be adopted for standardization and quality-control of herbal-formulations.
Oxidative stress and inflammatory reaction play critical roles in ischemia/reperfusion (I/R) injury in the brain. β-carotene (βCAR) is a naturally occurring pigment present in fruits and vegetables that expresses antioxidant and anti-inflammatory activities. This study was conducted to investigate the involvement of Bcl2/Bax and NF-κB signaling pathways in the potential protective role of βCAR against brain injury in a middle cerebral artery occlusion (MCAO) rat model. A focal brain ischemia model was created for 2 h, followed by reperfusion. Rats were given 10 and 20 mg/kg of βCAR for 7 days orally before induction of ischemia, at the start of reperfusion, and 3 days after ischemia. Scores of neurological deficit were rated 24 h after induction of ischemia. Motor coordination and spontaneous coordinate activities were assessed using rotarod and activity cage, respectively. After 2 h of the last dose, the animals were killed and their brains were extracted for further examinations. The results of the study show that βCAR diminished the score of neurological deficits and ameliorated motor coordination, balance, and locomotor activity in the I/R control group. Further, βCAR resulted in diminution of malondialdehyde (MDA) and augmentation of reduced glutathione (GSH) contents, as well as the elevation of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) enzyme activities in the brain homogenates of I/R rats. βCAR treatment significantly reduced nuclear factor kappa B (NF-κB) brain content and myeloperoxidase (MPO) activity and ameliorated the histological alterations in the brain tissues. βCAR significantly suppressed Bcl-2-associated X protein (Bax) and caspase-3 expression, as well as upregulated B-cell lymphoma-2 (Bcl-2) expression, suggesting a neuroprotective potential via downregulating NF-kB and protecting the rat brain against the I/R-associated apoptotic injury.
The genus Hibiscus contains about 275 species of flowering plants widely grown in the tropics and sub-tropics. The available literature revealed that several Hibiscus species exhibited excellent anticancer activity against several cancer cells like lung, breast, and liver. This motivated the authors to explore the anticancer property of other Hibiscus species (Hibiscus calyphyllus, H. deflersii and H. micranthus) along with development of a validated HPTLC method for the concurrent analysis of three anticancer biomarkers (ursolic acid, β-sitosterol and lupeol) in different Hibiscus species. The anticancer activity of various fractions (petroleum ether, toluene, dichloromethane, ethyl acetate and n-butanol) of all the Hibiscus species (aerial parts) were evaluated in vitro against HepG2 and MCF-7 cell lines using MTT assay. The HPTLC analysis was carried out using chloroform and methanol as mobile phase (97:3; v/v) on 20 × 10 cm glass-backed silica gel 60F254 plates and analyzed different phytoconstituents present in all fractions at λ = 575 nm wavelength. Of the tested fractions of H. calyphyllus, H. deflersii and H. micranthus, HdP (H. deflersii petroleum ether fraction) exhibited the most potent cytotoxic effect on HepG2 and MCF-7 (IC50: 14.4 and 11.1 μg/mL, respectively) cell lines. Using the developed HPTLC method a compact and intense peak of ursolic acid, β-sitosterol and lupeol were obtained at Rf = 0.22, 0.39 and 0.51, respectively. The LOD/LOQ (ng) for ursolic acid, β-sitosterol and lupeol were found as 42.30/128.20, 13.20/40.01 and 31.57/95.68, respectively in the linearity range 100-1200 ng/spot. The obtained result showed maximum presence of ursolic acid, β-sitosterol and lupeol (5.50, 11.85 and 7.47 μg/mg, respectively) in HdP which also supported its strong anticancer effect. Our data suggest that H. deflersii petroleum ether fraction (HdP) can be further subjected to the isolation of active cytotoxic phytoconstituents and establishment of their mechanism of action. The maiden developed HPTLC method for concurrent analysis of anticancer biomarkers may be further employed in the in process quality control of herbal formulation containing the said biomarkers.
In the present study, an attempt has been made to validate the claimed uses of 'Okra' Hibiscus esculentus in liver diseases. The preventive action of ethanolic extract of okra (EEO) against liver injury was evaluated in rodents using carbon tetrachloride-induced hepatotoxicity model. EEO, at 250 and 500 mg/kg body weight, exerted significant dose-dependent hepatoprotection by decreasing the CCl4-induced elevation of serum SGOT, SGPT, ALP, GGT, cholesterol, triglycerides and malondialdehyde (MDA) non-protein sulfhydryls (NP-SH) and total protein (TP) levels in the liver tissue. A significant reduction was also observed in pentobarbital-induced sleeping time in mice. The hepatoprotective and antioxidant activities of the extract are being comparable to standard silymarin. These findings were supported by histological assessment of the liver biopsy. The ability of okra extract to protect chemically induced liver damage may be attributed to its potent antioxidant property.
1 January 2010 in The American Journal of Chinese Medicine
The present study assessed the comparative antioxidant potential of the ethanol extract (EE) of leaves of four Acacia species (Acacia salicina, AS; Acacia laeta, AL; Acacia hamulosa AH; and Acacia tortilis, AT) grown in Saudi Arabia, including RP-HPTLC quantification of antioxidant biomarker rutin. In vitro DPPH radical scavenging and β-carotene-linoleic acid bleaching assays showed the promising antioxidant activities of Acacia extracts: ASEE (IC50: 60.39 and 324.65 μg/ml) >ALEE (IC50: 217.06 and 423.36 μg/ml) >ATEE (IC50: 250.13 and 747.50 μg/ml) >AHEE (IC50: 255.83 and 417.28 μg/ml). This was comparable to rutin tested at 500 μg/ml. Further, a RP- HPTLC densitometric method was developed (acetonitrile:water; 6:4; v/v) using glass-backed RP-18 silica gel F254 plate, and scanned at UV max 254 nm. The method was validated as per the ICH guidelines. Analysis of the validated RP-HPTLC displayed an intense peak (Rf = 0.65 ± 0.004) of rutin that was estimated (μg/mg dry weight) to be highest in ASEE (10.42), followed by ALEE (2.67), AHEE (1.36) and ATEE (0.31). Taken together, presence of rutin strongly supported the high antioxidant property of the tested Acacia species, especially Acacia salicina. The developed RP-HPTLC method therefore, affirms its application in the quality control of commercialized herbal drugs or formulation containing rutin.