Antidiabetic principles of Loranthus micranthus Linn. parasitic on Persea americana

Characterization, antibacterial, antioxidant, antidiabetic, and anti-inflammatory activities of green synthesized silver nanoparticles using Phragmanthera austroarabica A. G. Mill and J. A. Nyberg extract

Introduction

Diabetes mellitus is a chronic metabolic disorder that exhibited great expansion all over the world. It is becoming an epidemic disease adding a major burden to the health care system, particularly in developing countries.

Methods

The plant under investigation in the current study Phragmanthera austroarabica A. G. Mill and J. A. Nyberg is traditionally used in Saudi Arabia for the treatment of diabetes mellitus. The methanolic extract (200 mg/kg) of the plant and pure gallic acid (40 mg/kg), a major metabolite of the plant, as well as their silver nanoparticle formulae (AgNPs) were evaluated for their antidiabetic activity.

Results and Discussion

The results showed a decrease in body fat, obesity, an improvement in lipid profiles, normalization of hyperglycemia, insulin resistance, and hyperinsulinemia, and an improvement in liver tissue structure and function. However, the results obtained from AgNPs for both extract and the pure gallic acid were better in most measured parameters. Additionally, the activity of both the crude extract of the plant and its AgNPs were evaluated against a number of gram-positive, gram-negative bacteria and fungi. Although the activity of the crude extract ranged from moderate to weak or even non-active, the AgNPs of the plant extract clearly enhanced the antimicrobial activity. AgNPs of the extract demonstrated remarkable activity, especially against the Gram-negative pathogens Proteus vulgaris (MIC 2.5 μg/ml) and Pseudomonas aeruginosa (MIC 5 μg/ml). Furthermore, a promising antimicrobial activity was shown against the Gram-positive pathogen Streptococcus mutants (MIC 1.25 μg/ml).

Loranthus acaciae: Alternative medicine for β-lactamase producer and methicillin-resistant Staphylococcus aureus

Recently, we reported high antibacterial efficiency of Loranthus acaciae (LA) against different standard strains of bacteria including Methicillin-Resistant Staphylococcus aureus (MRSA). Therefore, this study aimed to confirm the effectiveness of LA against clinically isolated Staphylococcus aureus (SA) including β-lactamase producer (Blac) and MRSA. Forty-eight SA isolates collected from various clinical samples were used in this study. Antibiotics susceptibility profile was determined for twenty different antibiotics using automated Microscan Walkaway 96 Plus system as recommended by Clinical and Laboratory Standards Institute (CLSI) guidelines. This system also identified β-lactamase producers and MRSA. In the meantime, LA ethanolic extract was fractionated using liquid-liquid fraction method to hexane, dichloromethane DCM and methanol 80% fractions. Antimicrobial activities of LA extract and fraction were performed with agar well diffusion method for all SA isolates, MIC and MBC were also recorded. Phytochemical screening for various phyto-constituent classes of LA ethanolic extract was determined. Out of 48 SA isolates, Cefoxitin-positive MRSA represent 31 (64.6%), Blac 17 (35.4%), and 41 (85.4%) were multidrug-resistant SA, which was resistant at least to one antibiotic from three different categories. All isolates were resistant to ampicillin and penicillin. Antimicrobial activities of LA extract and fractions revealed that ethanol extract was active against all isolated SA with inhibition zone ranged from 33 ± 2.00 to 25 ± 3.05 mm. While DCM exhibited the largest inhibition zone range from 37 ± 3.00 to 33 ± 2.00 mm. This study is first of its kind conforming the high antibacterial activity of LA against SA isolated from a different source of infection. The study concluded that LA extract and fractions are active and give positive result for all isolated SA. Therefore, suitable pharmacological formulation of LA extract as a promising antibacterial agent for the treatment of SA infection should be given extreme priority.

Mechanism of antidiabetic effects of Plicosepalus Acaciae flower in streptozotocin-induced type 2 diabetic rats, as complementary and alternative therapy

Background

Diabetes and its related complications remain to be a major clinical problem. We aim to investigate the antidiabetic mechanistic actions of Plicosepalus Acaciae (PA) flowers in streptozotocin (STZ)-induced diabetic rats.

Methods

After diabetes induction, rats were divided randomly into five groups, including: 1) normal control group, 2) diabetic control group, 3) diabetic group treated with 150 mg/kg of ethanolic extract of PA flowers, 4) diabetic group treated with 300 mg/kg of ethanolic extract of PA flowers, and 5) diabetic group treated with 150 mg/kg of metformin. After 15 days of treatment; fasting blood glucose, glycated hemoglobin (HBA1c%), insulin, C-peptide, superoxide dismutase (SOD), catalase, reduced glutathione (GSH), malondialdehyde (MDA), triglyceride (TGs), total cholesterol (Tc), low density lipoprotein cholesterol (LDL-c), very LDL (VLDL), high DLc (HDL-c), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels were assessed. Histopathology of pancreas was also assessed.

Results

The results showed that PA flower ethanolic extract significantly reduced blood glucose, HBA1c%, MDA, TGs, Tc, VLDL, LDL-c, TNF-α, and IL-6 levels in a dose-dependent manner. All these parameters were already increased by diabetic induction in the untreated diabetic group. Treatment of diabetic rats with PA flower increased insulin, HDL-c, GSH, catalase, and SOD levels. Histological examination showed that the PA flower caused reconstruction, repair, and recovery of damaged pancreas when compared with the untreated group.

Conclusions

PA flower has a potential role in the management of diabetes as complementary and alternative therapy, due to its antioxidant, anti-inflammatory, hypolipidemic, hypoglycemic and insulin secretagogue effects.

Anticonvulsant and Neuroprotective Activities of Phragmanthera austroarabica Extract in Pentylenetetrazole-Kindled Mice

Anticonvulsant and neuroprotective activity of Phragmanthera austroarabica extract were tested in pentylenetetrazole-kindled mice. All the chemical constituents of the plant extract were identified. Additionally, the extract was standardized and proved to contain total phenolic contents equal to 379.92 ± 1.32 mg gallic acid equivalents/g dry plant extract. Induction of kindling was achieved by repeated intraperitoneal administration of pentylenetetrazole (35 mg/kg) twice weekly. Male albino mice were given P. austroarabica extract (200, 400, or 800 mg/kg). The two higher doses (400 or 800 mg/kg) of the extract significantly caused notable reduction in seizure activity and hippocampal malondialdehyde level compared to pentylenetetrazole control group. The highest dose enhanced cortical GSH level and showed intact DNA in the laddering assay. Upon studying the neuroprotective effect, mice treated with the higher dose of the extract demonstrated an improvement in the percent of surviving neurons in the cortex and hippocampus. We concluded that P. austroarabica extract ameliorated seizure activity and protected cortical and hippocampal neurons against pentylenetetrazole-induced kindling in mice.

Antidiabetic and hypolipidemic activities of ethanolic leaf extract and fractions of Melanthera scandens

OBJECTIVE

To evaluate the antidiabetic and hypolipidemic activities of ethanolic leaf extract and fraction of Melanthera scandens (M. scandens) in alloxan-induced diabetic rats.

METHODS

M. scandens leaf extract/fractions (37-111 mg/kg) were administered to alloxan-induced diabetic rats for 14 days and blood glucose levels (BGL) of the diabetic rats were monitored at intervals of 7 hours for acute study and 14 days for prolonged study. Lipid profiles of the treated diabetic rats were determined after the period of treatment.

RESULTS

Treatment of alloxan-induced diabetic rats with the extract/fractions caused a significant (P<0.001) reduction in fasting bloodglucose levels (BGL) of the diabetic rats both in acute study and prolonged treatment (2 weeks). The activities of the extract and fractions were more than that of the reference drug, glibenclamide. The extract/fractions exerted a significant reduction in the levels of serum total cholesterol, triglycerides, LDL and VLDL of extract with increases in HDL levels of the diabetic rats.

CONCLUSIONS

These results suggest that the leaf extract/fractions of M. scandens possesses antidiabetic effect on alloxan induced diabetic rats and this justifies its use in ethno medicine and can be exploited in the management of diabetes.

Antihyperglycemic effect of Hypericum perforatum ethyl acetate extract on streptozotocin-induced diabetic rats

OBJECTIVE

To evaluate the antihyperglycemic activity of ethyl acetate extract of Hypericum perforatum (H. perforatum) in streptozotocin (STZ)-induced diabetic rats.

METHODS

Acute toxicity and oral glucose tolerance test were performed in normal rats. Male albino rats were rendered diabetic by STZ (40 mg/kg, intraperitoneally). H. perforatum ethyl acetate extract was orally administered to diabetic rats at 50, 100 and 200 mg/kg doses for 15 days to determine the antihyperglycemic activity. Biochemical parameters were determined at the end of the treatment.

RESULTS

H. perforatum ethyl acetate extract showed dose dependant fall in fasting blood glucose (FBG). After 30 min of extract administration, FBG was reduced significantly when compared with normal rats. H. perforatum ethyl acetate extract produced significant reduction in plasma glucose level, serum total cholesterol, triglycerides, glucose-6-phosphatase levels. Tissue glycogen content, HDL-cholesterol, glucose-6-phosphate dehydrogenase were significantly increased compared with diabetic control. No death or lethal effect was observed in the toxic study.

CONCLUSIONS

The results demonstrate that H. perforatum ethyl acetate extract possesses potent antihyperglycemic activity in STZ induced diabetic rats.

Hypoglycaemic effect of Berberis vulgaris L. in normal and streptozotocin-induced diabetic rats

OBJECTIVE

To achieve a primary pharmacological screening contained in the aqueous extract of Berberis vulgaris (B. vulgaris) and to examine the hypoglycaemic effect and biochemical parameters of aqueous and saponins extract on groups of rats rendered diabetic by injection of streptozotocin.

METHODS

The phytochemical tests to detect the presence of different compounds were based on the visual observation of color change or formation of precipitate after the addition of specific reagents. Diabetes was induced in rats by intraperitoneal (i.p.) injection of streptozotocin (STZ) at a dose of 65 mg/kg bw. The fasting blood glucose levels were estimated by glucose oxidase-peroxidase reactive strips (Dextrostix, Bayer Diagnostics). Blood samples were taken by cutting the tip of the tail. Serum cholesterol and serum triglycerides were estimated by enzymatic DHBS colorimetric method.

RESULTS

Administration of 62.5 and 25.0 mg/kg of saponins and aqueous extract respectively in normal rats group shows a significant hypoglycemic activity (32.33% and 40.17% respectively) during the first week. However, diabetic group treated with saponin extract produced a maximum fall of 73.1% and 76.03% at day 1 and day 21 compared to the diabetics control. Also, blood glucose levels of the diabetic rats treated with aqueous extract showed decrease of 78.79% on the first day and the effect remains roughly constant during 3 week. Both extracts also declined significantly biochemical parameters (20.77%-49.00%). The control in the loss of body weight was observed in treated diabetic rats as compared to diabetic controls.

CONCLUSIONS

These results demonstrated significant antidiabetic effects and showed that serum cholesterol and serum triglycerides levels were decreased, significantly, consequently this plant might be of value in diabetes treatment.

Loranthus micranthus Linn.: Biological Activities and Phytochemistry

Loranthus micranthus Linn. is a medicinal plant from the Loranthaceae family commonly known as an eastern Nigeria species of the African mistletoe and is widely used in folkloric medicine to cure various ailments and diseases. It is semiparasitic plant because of growing on various host trees and shrubs and absorbing mineral nutrition and water from respective host. Hence, the phytochemicals and biological activities of L. micranthus demonstrated strong host and harvesting period dependency. The leaves have been proved to possess immunomodulatory, antidiabetic, antimicrobial, antihypertensive, antioxidant, antidiarrhoeal, and hypolipidemic activities. This review summarizes the information and findings concerning the current knowledge on the biological activities, pharmacological properties, toxicity, and chemical constituents of Loranthus micranthus.

Phytochemical analysis, hepatoprotective and antioxidant activity of Alchornea cordifolia methanol leaf extract on carbon tetrachloride-induced hepatic damage in rats

OBJECTIVE

To investigate the hepatoprotective and antioxidant activities of Alchornea cordifolia (A. cordifolia) leaf extract.

METHODS

Various solvent fractions of the methanol extract of the leaf of the plant A. cordifolia Mull. Arg (Fam: Euphorbiaceae) were evaluated for hepatoprotective activity by carbon tetrachloride-induced liver damage in rats. The degree of protection was measured by using biochemical parameters such as serum glutamate oxalate transaminase (SGOT/AST), serum glutamate pyruvate transaminase (SGPT/ALT), alkaline phosphatase (ALP) and total bilirubin. The in vitro antioxidant activity of the extract was also evaluated by the 1, 1-diphenyl- 2-picrylhydrazyl (DPPH) free radical scavenging assay. The extract was subjected to preliminary phytochemical screening.

RESULTS

The ethyl acetate and chloroform fractions, at a dose of 300 mg/kg, produced significant (P<0.05) hepatoprotection by decreasing the activities of the serum enzymes and bilirubin while there were marked scavenging of the DPPH free radicals by the fractions. The effects were comparable to those of the standard drugs used for the respective experiments, silymarin and ascorbic acid. Alkaloids, flavonoids, saponins and tannins were detected in the phytochemical screening.

CONCLUSION

From this study, it was concluded that the plant of A. cordifolia possesses hepatoprotective as well as antioxidant activities and these activities reside mainly in the ethyl acetate and acetone fractions of methanol leaf extract.

Evaluation of in vitro aldose reductase inhibitory potential of different fraction of Hybanthus enneaspermus Linn F. Muell

OBJECTIVE

To evaluate the aldose reductase inhibitory (ARI) activity of different fractions of Hybanthus enneaspermus for potential use in diabetic cataract.

METHODS

Total phenol and flavonoid content of different fractions was determined. ARI activity of different fractions in rat lens was investigated in vitro.

RESULTS

The results showed significant level of phenolic and flavonoid content in ethyl acetate fraction [total phenol (212.15±0.79 mg/g), total flavonoid (39.11±2.27 mg/g)] and aqueous fraction [total phenol (140.62±0.57 mg/g), total flavonoid (26.07±1.49 mg/g)] as compared with the chloroform fraction [total phenol (68.56±0.51 mg/g), total flavonoid (13.41±0.82 mg/g)] and petrolium ether fraction [total phenol (36.68±0.43 mg/g), total flavonoid (11.55±1.06 mg/g)]. There was a significant difference in the ARI activity of each fraction, and it was found to be the highest in ethyl acetate fraction [IC50 (49.26±1.76 µg/mL)] followed by aqueous extract [IC50 (70.83±2.82 µg/mL)] and it was least in the petroleum ether fraction [IC50 (118.89±0.71 µg/mL)]. Chloroform fraction showed moderate activity [IC50 (98.52±1.80 µg/mL)].

CONCLUSIONS

Different fractions showed significanct amount of ARI activity, where in ethyl acetate fraction it was found to be maximum which may be due to its high phenolic and flavonoid content. The extract after further evaluation may be used in the treatment of diabetic cataract.