Gastroprotective potential and mechanisms of action of Hedera nepalensis

Abstract Hedera nepalensis (H. nepalensis) , belonging to the family Araliaceae, is a medicinal plant traditionally used to treat stomach problems. The current study investigated the gastroprotective potential and the mechanism of action of H. nepalensis in diclofenac-and ethanol-induced ulcer models. Anti-oxidant and lipid peroxidation inhibitory prospects of H. nepalensis were checked out by free radical scavenging assay and UV spectrophotometer respectively. Effect of H. nepalensis on the pH, gastric total acidity of gastric juice and protective effects of H. nepalensis against ulcer models have been examined. Histopathological studies have been carried out. The aqueous methanol extract of H. nepalensis (100 µg/mL) showed anti-oxidant (83.55%) and lipid peroxidation inhibitory (70.88%) potential at 1000 µg/mL; the extract had no buffer potential. The extract (400 mg/kg) significantly (81.12% and 63.46%) showed gastroprotective effect in diclofenac and ethanol-induced rat ulcer models respectively. Histopathological studies confirmed the biochemical findings. FTIR analysis showed the presence of carboxylic acid, alkanes, conjugated alkanes, aldehydes and alkyl-aryl ethers. Gallic acid, M-coumaric acid and quercetin were found by HPLC analysis. H. nepalensis exhibited significant protection against diclofenac and ethanol induced gastric damage by anti-oxidant and lipid peroxidation suppression effects suggesting potential broad utility in treatment of diseases characterized with gastric damage.

Antidiabetic activity of aqueous extract of Sigesbeckia orientalis (St. Paul's Wort) in alloxan-induced diabetes model

The current study evaluated antidiabetic and antihyperlipidemic activities of aqueous extract of Sigesbeckia orientalis L. (St. Paul's Wort) (AESO) in an alloxan-induced diabetic rat model. Following OECD guidelines safe doses of AESO were assessed in rats for the main study. Serum/bood glucose, α-amylase, and lipids levels and histopathological evaluations were conducted to assess antidiabetic and associated antihyperlipidemic efficacies of AESO. AESO was found to be safe up to the dose of 2000 mg/kg. Significant (p < 0.05) reduction in glucose and lipids (total cholesterol, triglycerides, low-density lipoproteins) levels was observed in AESO treatment groups. Serum α-amylase, high-density lipoproteins, and total body weight was increased significantly (p < 0.05) in diabetic rats treated with AESO. Histopathological data showed improvement in hepatocyte and pancreatic β-cells islets architecture. HPLC analysis identified quercetin, gallic acid, vanillic acid, p-coumaric acid, m-coumaric acid and cinnamic acid in AESO which are suggested to be responsible for observed antihyperglycemic and antihyperlipidemic attributes. Further studies to standardise the extract and evaluation of safety profile in long-term toxicity studies are recommended for safe and effective antidiabetic nutraceuticals development.

Evaluation of in vitro and in vivo therapeutic efficacy of Ribes alpestre Decne in Rheumatoid arthritis

Rheumatoid arthritis is an autoimmune inflammatory disorder, despite the discovery of numerous drugs there is still need to introduce newer, safer and more effective sources of drugs such as medicinal herbs. Present research work was an attempt to appraise the antiarthritic potential of Ribes alpestre Decne in rheumatoid arthritis. In vitro inhibition of protein (bovine serum albumin and egg albumin) denaturation, Human red blood cell membrane stabilization assays along with formaldehyde induced arthritis in rats were commenced in this study. Findings of present investigation demonstrated significant and dose dependent antiarthritic effect of Ribes alpestre. Aqueous ethanolic extract, butanol and aqueous fraction illustrated 95%, 69.233% and 92.840% protection at 6400 ug/mL against bovine serum albumin denaturation respectively. Similarly, plant extract together with butanol and aqueous fractions showed 3653.47%, 1484.03% and 3563.19% inhibition of pathological alteration of egg albumin in that order. Moreover, hydroethanolic extract with butanol and aqueous fraction exhibited 91.29%, 65.73% and 89.62% stabilization against erythrocyte hemolysis at 6400 ug/mL correspondingly. Furthermore, hydroethanolic extract, butanol and aqueous fraction notably 73.49%, 66.42% and 68.87% decreased paw edema at highest dose (200 mg/kg). Similarly aqueous ethanolic extract, butanol and aqueous fraction illustrated 72.38%, 54.90% and 66.33% decrease in paw thickness at 200 mg/kg. Hence results suggested that Ribes alpestre possess antiarthritic potential thus supporting its use as natural remedy in rheumatic conditions.

Comparative hypoglycemic activity of different fractions of Thymus serpyllum L. in alloxan induced diabetic rabbits

The aim of present study was to evaluate and compare the hypoglycemic activity of different solvents extracts of Thymus serpyllum in rabbits. Diabetes was induced with single intravenous injection of alloxan monohydrate [150mg/kg]. Glibenclamide and acarbose were used as standard drugs. The crude powder of Thymus serpyllum [500 mg/kg b.w] significantly reduced blood glucose level in both normal and diabetic rabbits. Various extracts of Thymus serpyllum were compared for their hypoglycemic activity in diabetic rabbits. Ether and aqueous extracts significantly reduced the blood glucose level with maximum effect [p<0.001] produced by aqueous extract, which was selected for further study. Aqueous extract significantly inhibited the rise in glucose level in oral glucose tolerance test. The extract showed synergistic effect with different doses of insulin; however serum insulin level of the diabetic rabbits was not significantly increased by the extract. HbA1c level was significantly [p<0.05] reduced whereas hemoglobin level was significantly increased in three months study. Phytochemical screening of the aqueous extract showed the presence of alkaloids, flavonoids, tannins, terpinoids, reducing sugar and cardiac glycosides. It is concluded that the aqueous extract might be used alone or in combination with insulin to manage diabetes and its associated complications

Cardiotonic and vasoconstriction effects of aqueous methanolic extract of Paspalidium flavidum L.

The cardiovascular activity of aqueous methanolic extract of Paspalidium flavidum L. was evaluated on isolated rabbit heart and aorta. Heart rates, force of contraction and perfusion pressure were assessed in the presence of different concentrations of extract and adrenaline by using Langendorff's technique. Moreover, the vasoconstriction effects were studied in rabbit aorta using isolated organ bath. The results indicated that the extract [1ng-100[micro]g/ml] exhibited a significant increase in heart rate, contractility and perfusion pressure of isolated rabbit's heart; with a maximum effect at 1ng/ml, which was comparable to adrenaline [1[micro]g/ml]. Similarly, adrenaline at doses from 1-10[micro]g/ml produced a significant dose dependant increase in all the cardiac parameters. The cardiotonic effects of the extract were significantly blocked by propranolol [10[-5]M] while an increase in perfusion pressure was completely antagonized by verapamil [10[-6]M]. Activity of cardiac marker enzymes was also significantly raised in the perfusate of isolated heart pretreated with the extract. In rabbit aorta, the extract exhibited a dose dependent vasoconstriction effect however it did not increase the tone of aorta when pre-treated with verapamil [10[-6]M]. It is conceivable therefore; that the cardiotonic and vasoconstriction effects of the extract might be due to its agonistic actions on beta-receptors and Ca[+2] channels

Rationalization of Traditional Uses of Berberis lycium in Gastrointestinal Disorders.

Aims: Berberis lycium (Sumbal) is abundantly available in the northern areas of Pakistan and extensively used in local practice for the treatment of several human diseases. The objective of this study was to explore pharmacological basis for its use in gastrointestinal disorders. Materials and Methods: Crude aqueous (Bl.Aq) and methanolic (Bl.Meth) extracts of B. lycium were studied on isolated gut preparations of rabbit (jejunum) and guinea pig (ileum) by using in-vitro techniques. Tissues were mounted in tissue organ baths assembly containing physiological salt (Tyrode's) solution, maintained at 37ºC and aerated with carbogen, to assess the spasmogenic and spasmolytic effect and to find out the possible underlying mechanisms. Responses were measured on BioScience Powerlab data acquisition system by using isotonic transducers. Results: Phytochemical analysis indicates the presence of alkaloids, tannins and saponins in Bl.Aq and Bl.Meth. when tested on spontaneously contracting isolated rabbit jejunum, showed a dose-dependent spasmogenic effect at lower concentration (0.01-0.1 mg/mL) and (0.01-0.03 mg/mL), which was followed by spasmolytic effect at higher concentration (0.3-1.0 mg/mL) and (0.1-0.3 mg/mL) respectively. Pretreatment of the tissue with atropine (0.1 μM) partially suppressed the contractile effect. Bl.Aq and Bl.Meth caused complete inhibition of high K+ (80 mM)–induced contraction at 0.3 mg/mL and 0.1 mg/mL respectively and also produced a dose-dependent (0.01-0.03 mg/mL) rightward shift in the Ca++ concentration-response curve, similar to verapamil. When tested in bolus protocol on isolated guinea pig ileum, Bl.Aq and Bl.Meth caused a dosedependent spasmogenic effect at 0.01-0.1 mg/mL. Pretreatment of tissue with atropine (0.1 μM) partially suppress the contractile effect. Conclusions: Results indicate that spasmogenic effect was partially mediated through cholinergic activity and spasmolytic effect was mediated through calcium channel blocking activity (CCB), explain its traditional uses in diarrhea, intestinal cramps and other gastrointestinal intestinal disorders.

Formulation and in vitro evaluation of nateglinide microspheres using HPMC and carbopol-940 polymers by ionic gelation method

This study involves the design and characterization of Nateglinide [NAT] microspheres to enhance patient compliance. Ionic gelation technique was used to prepare Nateglinide Microspheres by using rate controlling polymers Carbopol-940 and Hydroxypropylmethyl cellulose [HPMC]. Shape and surface were evaluated with Scanning electron microscopy [SEM]. Percentage Yield, Particle size analysis, Encapsulating Efficiency, Micromeritic analysis, Fourier Transform Infra-Red Spectroscopy [FTIR], Differential Scanning Colorimetry [DSC] were done for characterization of Microspheres. Drug release studies were performed at pH 1.2 and 7.2 using USP dissolution type-2 apparatus and release rates were analyzed by the application of different pharmacokinetic models. The size of microspheres was found to be varied from 781 Micro m to 853 Micro m. Rheological studies proved excellent flow behavior while percentage yield was found to be varied from 72% to 79%. Absence of drug-polymers interactions was confirmed from FTIR and DSC results. The microspheres prepared with sodium alginate showed cracks while microspheres obtained from blend of Carbopol-940 plus sodium alginate were smooth and spherical. Maximum entrapment efficiency [71.4%] was achieved for Microspheres with Carbopol-940. The greater retardation in drug release was observed for microspheres containing Carbopol-940 and release pattern followed Higuchi kinetics model and negligible drug release was observed at pH 1.2

Phytochemical Analysis and Cardiac Depressant Activity of Aqueous Methanolic Extract of Morus nigra L. Fruit.

The present study was conducted to investigate the effects of aqueous methanolic extract of Morus nigra L. fruiton frog’s heart.Force of contraction and heart rate were measured by force displacement transducer attached to Power Lab data acquisition system. Lab chart Pro 5 software was used for the acquisition and analysis of data. The extract was also screened for various phytochemical constituents using standard methods. The results indicated that the extract produced a significant dose dependent decrease in heart rate without affecting the contractility of the heart. Phytochemical analysis also revealed that the extract contained flavonoids, cardiac glycosides,alkaloids, saponins and phenolic compounds.It is conceivable therefore; that the negative chronotropic effectsof aqueous methanolic extract of Morus nigra L. fruit may be attributed to the presence of certain pharmacologically active compounds.