Formulation and evaluation of antioxidant and antityrosinase activity of Polygonum amplexicaule herbal gel.

Medicinal plants are long been used for pharmaceutical and cosmetic industry. Among medicinal plants, Polygonum amplexicaule of family polygonaceae has traditional use in medicines and skin care. P. amplexicaule belongs to genus Polygonum that contains several important phytochemicals and considered as a rich source of antioxidants. The present study was designed to formulate herbal gel containing P. amplexicaule extract and evaluate its different physical properties as well as antioxidants and antityrosinase activities. Chitosan gel base was used as gelling agent and different gel formulations were prepared by different concentrations of extracts and polymers. Physical properties like pH, colour, odour, appearance and homogeneity, spreadability, extrudability and stability were optimized and analysed. A stable gel formulation containing 1% chitosan gel base and 5% plant extract was prepared that showed good appearance and homogeneity, easily spread ability and excellent extrudability. This gel formulation was tested for antioxidant and skin whitening properties by DPPH free radical scavenging assay and tyrosinase inhibition assay respectively and ascorbic acid was used as reference standard. DPPH scavenging activity with an IC50 value of 0.446 mg/mL and tyrosinase inhibition activity with an IC50 value of 0.805 mg/mL was observed and results indicated that this herbal gel formulation has a good potential for cosmetic use.

Studies on two polyherbal formulations (ZPTO and ZTO) for comparison of their antidyslipidemic, antihypertensive and endothelial modulating activities.

BACKGROUND: Cardiovascular disorders (CVDs) are the leading cause of disease burden worldwide. Apart from available synthetic drugs used in CVDs, there are many herbal formulations including POL-10 (containing 10 herbs), which have been shown to be effective in animal studies but POL-10 was found to cause tachycardia in rodents as its side effect. This study was designed to modify the composition of POL-10 for better efficacy and/or safety profile in CVDs. METHODS: To assess the antidyslipidemic, antihypertensive and endothelial modulatory properties of two herbal formulations, (ZPTO and ZTO) containing Z: Zingiber officinalis, P: Piper nigrum, T: Terminalia belerica and O: Orchis mascula, different animal models including, tyloxapol and high fat diet-induced dyslipidemia and spontaneously hypertensive rats (SHR) were used. Effect on endothelial function was studied using isolated tissue bath set up coupled with PowerLab data acquisition system. The antioxidant activity was carried out using DPPH radical-scavenging assay. RESULTS: Based on preliminary screening of the ingredients of POL-10 in tyloxapol-induced hyperlipidemic rats, ZPTO and ZTO containing four active ingredients namely; Z, P, T and O were identified for further studies and comparison. In tyloxapol-induced hyperlipidemic rats, both ZPTO and ZTO caused significant reduction in serum triglyceride (TG) and total cholesterol (TC). In high fat diet-fed rats, ZPTO decreased TC, low-density lipoproteins cholesterol (LDL-C) and atherogenic index (AI). ZTO also showed similar effects to those of ZPTO with additional merits being more effective in reducing AI, body weight and more importantly raising high-density lipoproteins. In SHR, both formulations markedly reduced systolic blood pressure, AI and TG levels, ZTO being more potent in reversing endothelial dysfunction while was devoid of cardiac stimulatory effect. In addition, ZTO also reduced LDL-C and improved glucose levels in SHR. In DPPH radical-scavenging activity test, ZTO was also more potent than ZPTO. CONCLUSION: The modified formulation, ZTO was not only found more effective in correcting cardiovascular abnormalities than ZPTO or POL-10 but also it was free from tachycardiac side-effect, which might be observed because of the presence of Piper nigrum in ZPTO.

Pharmacological basis for the medicinal use of psyllium husk (Ispaghula) in constipation and diarrhea.

BACKGROUND: The objective of this study was to determine the pharmacological basis of the medicinal use of psyllium husk (Ispaghula) in gastrointestinal motility disorders. METHODS: In-vivo studies were conducted on mice, and isolated rabbit jejunum and guinea-pig ileum were used in in-vitro experiments. RESULTS: The crude extract of Ispaghula (Po.Cr) had a laxative effect in mice at 100 and 300 mg/kg, which was partially sensitive to atropine or SB203186 (5-HT(4) antagonist). At higher doses (500 and 1,000 mg/kg), Po.Cr had antisecretory and antidiarrheal activity. In guinea-pig ileum, Po.Cr (1-10 mg/ml) had a stimulatory effect, which was partially sensitive to atropine or SB203186. In rabbit jejunum, Po.Cr had a partially atropine-sensitive stimulatory effect followed by relaxation at 10 mg/ml. The relaxation was inhibited by the presence of L-NAME, a nitric oxide (NO) synthase inhibitor, or methylene blue, a guanylyl cyclase inhibitor. Similarly, the relaxant effect of Po.Cr on K(+) (80 mM)-induced contractions, was attenuated in the presence of L-NAME or methylene blue. Activity-directed fractionation of Po.Cr revealed that the gut stimulatory and inhibitory constituents were widely distributed in the aqueous and organic fractions. CONCLUSION: This study demonstrates that Ispaghula has a gut-stimulatory effect, mediated partially by muscarinic and 5-HT(4) receptor activation, which may complement the laxative effect of its fiber content, and a gut-inhibitory activity possibly mediated by blockade of Ca(2+) channels and activation of NO-cyclic guanosine monophosphate pathways. This may explain its medicinal use in diarrhea. It is, perhaps, also intended by nature to offset an excessive stimulant effect.

Studies on antidyslipidemic effects of Morinda citrifolia (Noni) fruit, leaves and root extracts.

BACKGROUND: The objective of present study was to provide the pharmacological basis for the medicinal use of Morinda citrifolia Linn in dyslipidemia using the aqueous-ethanolic extracts of its fruits (Mc.Cr.F), leaves (Mc.Cr.L) and roots (Mc.Cr.R). RESULTS: Mc.Cr.F, Mc.Cr.L and Mc.Cr.R showed antidyslipidemic effects in both triton (WR-1339) and high fat diet-induced dyslipidemic rat models to variable extents. All three extracts caused reduction in total cholesterol and triglyceride levels in triton-induced dyslipidemia. In high fat diet-induced dyslipidemia all these extracts caused significant reduction in total cholesterol, triglyceride, low density lipoprotein-cholesterol (LDL-C), atherogenic index and TC/HDL ratio. Mc.Cr.R extract also caused increase in high density lipoprotein-cholesterol (HDL-C). The Mc.Cr.L and Mc.Cr.R reduced gain in body weight with a reduction in daily diet consumption but Mc.Cr.F had no effect on body weight and daily diet consumption. CONCLUSIONS: These data indicate that the antidyslipidemic effect of the plant extracts was meditated through the inhibition of biosynthesis, absorption and secretion of lipids. This may be possibly due partly to the presence of antioxidant constituents in this plant. Therefore, this study rationalizes the medicinal use of Morinda citrifolia in dyslipidemia.

Antispasmodic and vasodilator activities of Morinda citrifolia root extract are mediated through blockade of voltage dependent calcium channels.

BACKGROUND: Morinda citrifolia (Noni) is an edible plant with wide range of medicinal uses. It occurs exclusively in tropical climate zone from India through Southeast Asia and Australia to Eastern Polynesia and Hawaii. The objective of this study was to explore the possible mode(s) of action for its antispasmodic, vasodilator and cardio-suppressant effects to rationalize its medicinal use in gut and cardiovascular disorders. METHODS: Isolated tissue preparations such as, rabbit jejunum, rat and rabbit aorta and guinea pig atria were used to test the antispasmodic and cardiovascular relaxant effects and the possible mode of action(s) of the 70% aqueous-ethanolic extract of Morinda citrifolia roots (Mc.Cr). RESULTS: The Mc.Cr produced a concentration-dependent relaxation of spontaneous and high K(+) induced contractions in isolated rabbit jejunum preparations. It also caused right ward shift in the concentration response curves of Ca(++), similar to that of verapamil. In guinea-pig right atria, Mc.Cr caused inhibition of both atrial force and rate of spontaneous contractions. In rabbit thoracic aortic preparations, Mc.Cr also suppressed contractions induced by phenylephrine (1.0 µM) in normal- Ca(++) and Ca(++)-free kreb solutions and by high K(+), similar to that of verapamil. In rat thoracic aortic preparations, Mc.Cr also relaxed the phenylephrine (1.0 µM)-induced contractions. The vasodilatory responses were not altered in the presence of L-NAME (0.1 mM) or atropine (1.0 µM) and removal of endothelium. CONCLUSIONS: These results suggest that the spasmolytic and vasodilator effects of Mc.Cr root extract are mediated possibly through blockade of voltage-dependent calcium channels and release of intracellular calcium, which may explain the medicinal use of Morinda citrifolia in diarrhea and hypertension. However, more detailed studies are required to assess the safety and efficacy of this plant.

Antihypertensive, antidyslipidemic and endothelial modulating activities of Orchis mascula.

The objective of this study was to investigate the possible mode(s) of action for the medicinal use of Orchis mascula (OM) (family Orchidaceae) in hypertension and dyslipidemia. In spontaneously hypertensive rats (SHRs), OM significantly (P<0.05) reduced systolic blood pressure to 174.2+/-9.63 vs. 203.4+/-7.13 mm Hg (mean+/-s.e.m.; n=7-10) and improved endothelial dysfunction by increasing acetylcholine-induced relaxation. In normotensive anesthetized rats, the crude extract of OM (Om.Cr) at 10 and 30 mg kg(-1) caused a dose-dependent attenuation of mean arterial pressure. OM also decreased serum triglycerides to 29.28+/-6.99 vs. 93.84+/-5.7 mg per 100 ml (P<0.001), low-density lipoprotein-cholesterol to 5.99+/-1.27 vs. 21.9+/-3.5 mg per 100 ml (P<0.05) and atherogenic index to 0.096+/-0.017 vs. 0.36+/-0.08 mg per 100 ml (P<0.05). OM significantly reduced lipid levels in tyloxapol and high fat diet-induced hyperlipidemia. In a second model, OM also reduced gain in body weight with a reduction in daily diet consumption. In isolated rabbit aorta, Om.Cr caused concentration-dependent relaxation of both phenylephrine and high K(+) (80 mM)-induced contractions and a rightward shift of the calcium concentration-response curves similar to the effect seen with verapamil. In conclusion, OM shows antihypertensive and endothelial-modulating effects mediated through multiple pathways that include direct vasodilation by calcium channel blockade and reduction of plasma lipids by inhibition of biosynthesis, absorption and secretion. This study rationalizes the medicinal use of OM in hypertension and dyslipidemia. However, further studies are required to identify the active constituents of this plant.

Antihypertensive, antioxidant, antidyslipidemic and endothelial modulating activities of a polyherbal formulation (POL-10).

The present investigation was aimed at providing the pharmacological basis for the medicinal use of a polyherbal formulation (POL-10) in hypertension and dyslipidemia. In spontaneously hypertensive rats, POL-10 significantly (p<0.05) reduced blood pressure to 183.2+/-2.97 vs 198.1+/-5.2 mmHg (Mean+/-S.E.M; n=7-10), improved endothelial dysfunction (p<0.01) by increasing acetylcholine-induced relaxation up to 46.0+/-6.7% vs 24.6+/-3.8% (n=5-10) and decreased serum triglycerides (TG) to 54.5+/-3.3 vs. 93.84+/-5.7 mg/dl (p<0.001). In high fat diet-induced hypercholesterolemia, POL-10 caused reduction in total cholesterol (TC), low density lipoproteins (LDL) levels and the atherogic index (TC-HDL/HDL). It decreased TG levels in tyloxapol-induced hyperlipidemia and increased high-density lipoprotein cholesterol (HDL-C) and reduced atherogenic index in normotensive rats. It exhibited strong antioxidant activity in different in vitro assays. In isolated smooth muscle preparation, POL-10 exhibited calcium channel blocking (CCB) activity by inhibition of high K(+)- induced contractions and rightward shift of Ca(++) concentration-response curves similar to that of verapamil. In conclusion, these findings rationalize the medicinal use of POL-10 in cardiovascular disorders which are mediated through multiple pathways such as, antioxidant, CCB, inhibition of lipid biosynthesis and absorption.

The presence of antiamoebic constituents in psyllium husk.

The crude extract of psyllium husk (ispaghula) and its active constituent (petroleum fraction) caused varying degrees of growth inhibition in three different species of Entamoeba, i.e. Entamoeba histolytica, E. invadens and E. dispar. The inhibitory effect of the crude extract was in the dose range of 1-10 mg/mL, whereas a similar inhibitory effect was obtained with the petroleum fraction at a much lower dose (0.1-1.0 mg/mL), indicating that the active chemical(s) is/are concentrated in the petroleum fraction. These data support the traditional use of psyllium husk in amoebic dysentery.