Rabea Parveen

Oil based nanocarrier for improved oral delivery of silymarin: In vitro and in vivo studies

Silymarin, obtained from Silybum marianum is used for hepatoprotection and having poor aqueous solubility and low bioavailability. Therefore, it was thought to incorporate the drug into oil-in-water (o/w) based nanocarrier to increase its oral bioavailability. In the present study, o/w nanocarrier was prepared by titration method and was characterized for droplet size, viscosity, etc. In vitro drug release was carried out by dialysis membrane method. A pharmacokinetic study was performed to determine maximum plasma concentration (C(max)), area under the curve (AUC), etc. and hepatoprotective activity was evaluated in terms of serum enzyme estimation. The optimized nanoemulsion formulation consisted of sefsol-218 as oil, tween 80 as a surfactant and ethanol as a co-surfactant having nano-droplet size and low viscosity. In vitro dissolution studies showed higher drug release from nanoemulsion as compared to bulk drug suspension. The AUC and C(max) of nanoemulsion after oral administration were 4-fold and 6-fold higher than those of drug suspension of silymarin. The results of pharmacokinetic studies showed better effects of developed nanoemulsion than drug suspension and marketed formulation. The present study showed that the nanoemulsion being a versatile technology has the potential to improve the biopharmaceutics properties of silymarin.

Effects of Silymarin Nanoemulsion against Carbon Tetrachloride- induced Hepatic Damage

Silymarin is a complex mixture of four flavonolignan isomers (silybin, isosilybin, silydianin and silychristin) obtained from ‘milk thistle’ (Silybum marianum). This plant compound is used almost exclusively for hepatoprotection. Because of its low and poor oral bioavailability, silymarin was formulated as a nanoemulsion to increase its solubility (and so its oral bioavailability) as well as therapeutic activity. The present study assessed the hepatoprotective activity on Wistar rats by determining biochemical parameters and histopathological properties of the nanoemulsion formulation of silymarin against carbon tetrachloride (CCl4)-induced hepatotoxicity. Hepatoprotective activity was evaluated by the activity of serum alkaline phosphatase, alanine transaminase and aspartate transaminase; antioxidative defence markers (concentration of reduced glutathione); oxidative stress parameter (thiobarbituric acid reactive substances) and liver histopathology. The nanoemulsion-treated group showed significant decreases in glutamate oxaloacetate transaminase, pyruvate transaminase, alkaline phosphotase, total bilirubin and tissue lipid peroxides and increased total protein, albumin, globulin and tissue glutathione as compared to toxicant. The results indicate an excellent potential of the nanoemulsion formulation for the reversal of CCl4-induced liver toxicity in rats as compared to standard silymarin.

Stability-indicating HPTLC method for quantitative estimation of silybin in bulk drug and pharmaceutical dosage form.

In the present study a novel stability-indicating high-performance thin-layer chromatography (HPTLC) method for quantitative determination of silybin in bulk drug and nanoemulsion formulation has been developed and validated on silica using solvent chloroform-acetone-formic acid (9 : 2 : 1 v/v/v) (R(f )of silybin 0.46 +/- 0.05) in the absorbance mode at 296 nm. The method showed a good linear relationship (r(2) +/- 0.999) in the concentration range 25-1500 ng per spot. It was found to be linear, accurate, precise, specific, robust and stability-indicating and can be applied for quality control and standardization of several multi-component hepatoprotective formulations as well as for stability testing of different dosage forms. The method proposed was also used to investigate the kinetics of acidic and alkaline degradation processes by quantification of drug at different temperature to calculate the activation energy and half-life for silymarin degradation.

Solid lipid nanoparticles of anticancer drug andrographolide: formulation, in vitro and in vivo studies.

Abstract Diterpenoidal anti-cancer drug andrographolide (AD) was encapsulated into solid lipid nanoparticle (SLN) because of poor aqueous solubility and high lipophilicity. AD-SLNs were prepared by solvent injection method and characterized for droplet size, surface morphology, zeta potential, etc. In vitro drug release was carried out by dialysis-membrane method. A pharmacokinetic study was performed by UPLC/Q-TOF-MS method to determine the maximum plasma concentration (Cmax), area under the curve (AUC), etc. There was an improvement in Cmax and AUC of AD-SLNs when compared with AD, thereby enhancing the bioavailability of AD. The tmax was increased than that of AD suspension, indicating the sustained release pattern of AD-SLNs. The antitumor activity was carried out on Balb/c mice showing better results with AD-SLNs as compared to AD. Thus, the AD-loaded SLNs would be useful for delivering poorly water-soluble AD with enhanced bioavailability and improved antitumor activity.

Challenges and guidelines for clinical trial of herbal drugs

World Health Organization (WHO) has defined herbal medicines as finished labeled medicinal product that contain an active ingredient, aerial, or underground parts of the plant or other plant material or combinations. According to a report of WHO, about 80% of the world population is reported to rely on traditional medicine for their primary health care needs. Even in the developed countries, complementary or alternative medicine is gaining popularity. A report of a global survey on national policy on traditional medicine and regulation of herbal medicines indicated that about 50 countries including China, Japan, and Germany already have their national policy and laws on regulations of traditional medicines. Herbal drugs possess a long history of its use and better patient tolerance. These are cheaper and easily available in countries like India due to rich agro culture conditions. However, reckless utilization of resources threatens the sustainability of several plant species. Traditional medicines are governed by the Drugs and Cosmetics Act of 1940 and the Drugs and Cosmetics Rules of 1945. In 1959, the Government of India amended the Drugs and Cosmetics Act to include drugs that are derived from traditional Indian medicine. In 1993, the guidelines for the safety and efficacy of herbal medicines developed by an expert committee directed that the procedures laid down by the office of the Drug Controller General of India for allopathic drugs should be followed for all traditional and herbal products to enter into clinical trials for any therapeutic condition. However, there are certain loop holes in the clinical trials of herbal drugs as the lack of stringent bylaws and regulations. Hence, a deep insight of important challenges and major regulatory guidelines for clinical trial of herbal drugs and botanicals is discussed in the present communication. There is lack of scientific evidence to evaluate safety and efficacy of herbal drugs. The quality of the trial drug has to be tested for batch-to-batch uniformity of the active constituents. It is very difficult to have active and control groups with identical color, smell and taste of the herbal drug, which cannot be imitated while manufacturing a placebo. These challenges can be reduced or overcome by applying most recent methodologies and guidelines for clinical trials. Since the quality control of herbal medicines is complicated and difficult, relevant and appropriate requirements should be established for the assessment of safety and efficacy for different categorized herbal medicines to reduce cost and expenditure. And, efforts should be made for the integration of traditional medicine into national healthcare systems. Different challenges and regulatory guidelines discussed for the clinical trial of herbal drugs will be useful for various industries for considering it before going ahead for clinical trial of their product.

Development and validation of HPLC method for simultaneous estimation of piperine and guggulsterones in compound Unani formulation (tablets) and a nanoreservoir system

An attempt has been made to develop and validate a simultaneous HPLC method for novel approach of drug release via oil-in-water (o/w) nanoemulsion formulation and Habb-e-Khardal Unani tablet containing piperine and guggul sterones E and Z as main ingredients. Nanoemulsion was prepared by titration method using sefsol-218 as an oily phase, cremophor-EL as a surfactant, transcutol as a co-surfactant and distilled water as an aqueous phase. The formulation was optimized on the basis of thermodynamic stability and dispersibilty test. The nanoformulation was evaluated for particle size, surface morphology, electrical conductivity and viscosity determination. The in vitro dissolution was carried out by dialysis bag method. Drugs were quantified using an HPLC method developed in-house with a C(18) column as stationary phase and acetonitrile and water as mobile phase at λ(max) of 240 nm. The optimized formulation showed higher drug release, lower droplet size and less viscosity as compared with the conventional Habb-e-Khardal Unani tablet. The present study illustrated the potential of nanoemulsion dosage form in improving biopharmaceutic performance of piperine and guggul sterone. The HPLC method was also found to be quite sufficient for the routine quality control of formulations containing piperine and guggul sterone E and Z as ingredients and also for in vitro drug release studies.

Development and validation of a stability-indicating HPTLC method for analysis of arjunolic acid in a herbal formulation

The stem bark of Terminalia arjuna Linn. (family: Combretaceae), commonly known as Arjuna in Indian systems of medicine, is an important drug widely used in the preparation of Ayurvedic and Unani formulations used in cardioprotection [1, 2]. T. arjuna stem bark is reported to contain different groups of chemical constituents, for example hydrolyzable tannins [2, 3], triterpene acids, flavanoids, phenolics, and phyto sterols [3]. Important triterpene acids are arjunetin, arjunic acid, arjunolic acid, and arjungenin [4–6]. Arjunolic acid (2,3,23-trihydroxyolean-12-en-28-oic acid; Figure 1) is used for its hypotensive effect and as an antioxidant, antiallergic, and antiasthmatic [6]. HPTLC and HPLC methods have been reported for analysis of arjunolic acid in the crude form [7–9] but the methods lack proper validation. Because no stability-indicating analytical method had been reported for quantification of arjunolic acid in pharmaceutical or herbal dosage forms it was thought worthwhile to develop a stability-indicating HPTLC method. The proposed method will be useful for standardization and quality control of formulations which contain arjunolic acid or arjuna as an ingredient.

Pharmacological evidences for cytotoxic and antitumor properties of Boswellic acids from Boswellia serrata

ETHNOPHARMACOLOGICAL RELEVANCE Increasing research on traditional herbal medicines and their phytoconstituents has recognized their usefulness in complementary as adjuvant to chemotherapy in various types of cancers. The oleo-gum resin of Boswellia serrata tree is one such folk medicine, which has been traditionally used for religious, cosmetic as well as medical purposes since ages. The oleo-gum resin of the plant has been used in traditional medicine to treat variety of conditions including inflammatory diseases like arthritis, asthma, chronic pain, bowel conditions and many other diseases. This review presents an overview of scientific studies on cytotoxic and antitumor properties of B. serrata and its constituents. MATERIALS AND METHODS Literature search was carried out for activities of B. serrata and various isolated boswellic acids such as β-boswellic acid, 11-keto-β-boswellic acid and acetyl-11-keto-β-boswellic acid reported in various cancer types in vitro as well as in vivo. RESULTS The triterpenoidal fraction of B. serrata (containing boswellic acids) is responsible for the cytotoxic and antitumor properties. Among the screened compounds, 3-O-acetyl-11-keto-β-boswellic acid has been found to be most promising cytotoxic molecule. The cytotoxic and antitumor effects are mainly due to induction of apoptosis through caspase activation, increased Bax expression, NF-κB down regulation and induction of poly (ADP)-ribose polymerase (PARP) cleavage. CONCLUSIONS Boswellic acids appear to be promising candidates for anticancer drug development in future. However, further in vivo studies are needed. Studies in combination with clinically used anticancer drugs and QSAR studies on individual boswellic acid also need to be carried out.

Rapid RP-HPLC Method for the Quantification of Glabridin in Crude Drug and in Polyherbal Formulation

A simple, economic, selective, precise and robust method has been developed and validated for the analysis of glabridin in crude drugs and polyherbal formulations. Reversed-phase chromatography is performed on a C18 column with water and acetonitrile as mobile phase in gradient elution method at a flow rate of 1 mL/min. Detection is performed at 230 nm and a sharp peak is obtained for glabridin at a retention time of 14.9 ± 0.02 min. Linear regression analysis data for the calibration plot showed a good linear relationship between response and concentration in the range of 1-500 µg/mL; the regression coefficient is 0.9992 and the linear regression equation is y = 26.683x - 142.17. The method is validated for accuracy, precision, reproducibility, robustness and detection and quantification limits, in accordance with International Conference on Harmonization guidelines. Statistical analysis proved that the method is precise, reproducible, selective and accurate for the analysis of glabridin. The proposed, developed and validated high-performance liquid chromatography method for the quantification of glabridin can be used for the quality control and standardization of licorice (Glycyrrhiza glabra Linn.) and different herbal formulations in which licorice is present as a constituent.

Hypoglycemic Potential of Aqueous Extract of Moringa oleifera Leaf and In Vivo GC-MS Metabolomics

Moringa oleifera Lam. (family; Moringaceae), commonly known as drumstick, have been used for centuries as a part of the Ayurvedic system for several diseases without having any scientific data. Demineralized water was used to prepare aqueous extract by maceration for 24 h and complete metabolic profiling was performed using GC-MS and HPLC. Hypoglycemic properties of extract have been tested on carbohydrate digesting enzyme activity, yeast cell uptake, muscle glucose uptake, and intestinal glucose absorption. Type 2 diabetes was induced by feeding high-fat diet (HFD) for 8 weeks and a single injection of streptozotocin (STZ, 45 mg/kg body weight, intraperitoneally) was used for the induction of type 1 diabetes. Aqueous extract of M. oleifera leaf was given orally at a dose of 100 mg/kg to STZ-induced rats and 200 mg/kg in HFD mice for 3 weeks after diabetes induction. Aqueous extract remarkably inhibited the activity of α-amylase and α-glucosidase and it displayed improved antioxidant capacity, glucose tolerance and rate of glucose uptake in yeast cell. In STZ-induced diabetic rats, it produces a maximum fall up to 47.86% in acute effect whereas, in chronic effect, it was 44.5% as compared to control. The fasting blood glucose, lipid profile, liver marker enzyme level were significantly (p < 0.05) restored in both HFD and STZ experimental model. Multivariate principal component analysis on polar and lipophilic metabolites revealed clear distinctions in the metabolite pattern in extract and in blood after its oral administration. Thus, the aqueous extract can be used as phytopharmaceuticals for the management of diabetes by using as adjuvants or alone.