Ranjit K. Harwansh

Enhancement of photoprotection potential of catechin loaded nanoemulsion gel against UVA induced oxidative stress.

The present study was aimed to develop a catechin (CA) loaded nanoemulsion based nano-gel for the protection of skin against ultraviolet radiation (UV) induced photo-damage and to ensure its enhanced skin permeability as well as bioavailability through transdermal route. The optimized nanoemulsion (CA-NE4) was prepared by spontaneous nano-emulsification method. It was composed of oil (ethyl oleate), Smix [surfactant (span 80) and co-surfactant (transcutol CG)] and aqueous system in an appropriate ratio of 15:62:23% w/w respectively. The CA-NE4 was characterized through assessment of droplet size, zeta potential, refractive index, transmission electron microscopy (TEM), UV, high performance thin layer chromatography (HPTLC) and Fourier transform infrared spectroscopy (FTIR) analysis. The average droplet size and zeta potential of CA-NE4 were found to be 98.6±1.01nm and -27.3±0.20mV respectively. The enhanced skin permeability was better with CA-NE4 based nano-gel (CA-NG4) [96.62%] compared to conventional gel (CA-CG) [53.01%] for a period of 24h. The enhanced % relative bioavailability (F) of CA (894.73), Cmax (93.79±6.19ngmL(-1)), AUC0-t∞ (2653.99±515.02nghmL(-1)) and Tmax (12.05±0.02h) was significantly obtained with CA-NG4 as compared to oral suspension for extended periods (72h). CA-NG4 could improve the level of cutaneous antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) and reduce the level of thiobarbituric acid reactive substances (TBRAS) against oxidative stress induced by UVA. Nano-gel formulation of CA showed sustained release profile and enhanced photoprotection potential due to its improved permeability as well as bioavailability (P<0.05) compared to the conventional gel. Therefore, transdermal administration of nano-gel (CA-NG4) of CA offers a better way to develop the endogenous cutaneous protection system and thus could be an effective strategy for decreasing UV-induced oxidative damage in the skin tissues.

Enhanced permeability of ferulic acid loaded nanoemulsion based gel through skin against UVA mediated oxidative stress.

AIMS The study was aimed to develop a ferulic acid (FA) loaded nanoemulsion based gel in order to ensure the enhanced permeability and maximum antioxidant activity against UVA induced oxidative stress in rat. MAIN METHODS The optimized ferulic acid loaded nanoemulsion 3 (FA-NE3) was prepared by spontaneous nano-emulsification method with an appropriate ratio (20:30:50% w/w) of the oil (isostearyl isostearate), aqueous system and Smix [surfactant (labrasol) and co-surfactant (plurol isostearique)] respectively. FA-NE3 was characterized by measuring their droplet size, zeta potential, refractive index, transmission electron microscopy (TEM), ultraviolet (UV), fourier transform infrared spectroscopy (FTIR) and rheological characteristics. Ex vivo skin permeation and in vivo UVA protection activity of FA-NE3 based nano-gels (FA-NG3) along with placebo were studied through the rat skin. KEY FINDINGS FA-NE3 exhibited sustained-release profile, better permeability and ultraviolet A (UVA) protection activity as compared to conventional dosage form. This phenomenon may be attributed towards increased solubility of the drug and enhanced permeability from nanoemulsion. FA-NE3 based nanogel (FA-NG3) could elevate the level of skin marker enzymes against oxidative stress mediated by UVA. SIGNIFICANCE The gel formulation exhibited significant (P<0.01) skin permeability and antioxidant activity in the current investigations. The nanogel could be promising nanocarriers for topical delivery of FA in response to better skin protection activity against UVA rays in a sustained manner.

CYP450 mediated inhibition potential of Swertia chirata: An herb from Indian traditional medicine.

ETHNOPHARMACOLOGICAL RELEVANCE An Ayurvedic herb, Swertia chirata (SC) have been used in treating various ailments such as hyperglycemia, leishmania, liver infections, inflammation, abdominal pain, bacterial infection, malaria etc. in Indian Systems of Medicine (ISM). AIM OF THE STUDY Study was designed to investigate the inhibition potential of the standardized SC extract along with its bioactive molecule ursolic acid on hepatic drug metabolizing isozymes (CYP3A4 and CYP2D6) and further some heavy metals were also analysed of the plant material. MATERIALS AND METHODS The hydro-alcoholic extract was standardized with standard ursolic acid by reverse phase-high performance liquid chromatography (RP-HPLC) method and the heavy metals content were analyzed through atomic absorption spectroscopy (AAS). The effect of extract on rat liver microsome (RLM) and individual CYP isozymes (CYP3A4 and CYP2D6) was investigated through CYP450-CO complex assay and fluorescence microplate assay respectively. RESULTS The content of ursolic acid was found to be 2.66% (w/w) in the SC extract and heavy metal contents along with trace elements were within the prescribed limits as per WHO guidelines. The inhibitory potential of SC extract on RLM was found to be 23.64±1.80%. CYP3A4 and CYP2D6 inhibitory effect of SC and ursolic acid (IC50: 197.49±2.68, 211.45±3.54 and IC50: 229.25±2.52, 212.66±1.26 µg/mL) was less as compared to that known inhibitors, ketoconazole and quinidine respectively. CONCLUSIONS The current study revealed that S. chirata has less inhibition potential with two major drug metabolizing isozymes CYP3A4 and CYP2D6. SC extract and ursolic acid showed significantly (P<0.001) less inhibitory potential on RLM. The Ayurvedic herb (SC) has shown less inhibitory activity in a concentration dependent manner against the tested two CYP450 enzymes. The tested heavy metals and trace elements present SC was within limit. Therefore, the traditional use of S. chirata may be safe in respect of both tested isozymes.

RP-HPLC simultaneous estimation of betulinic acid and ursolic acid in Carissa spinarum

Carissa spinarum is a well-known medicinal plant which has been reported for its anthelmintic, antipyretic, antiviral, antimicrobial and antitumour activities. In this study, a reverse-phase high-performance liquid chromatographic method was developed for the simultaneous estimation of betulinic acid (BA) and ursolic acid (UA) in the methanol extract of C. spinarum root. The method was further validated for linearity, limit of detection (LOD = 3.3σ/S), limit of quantification (LOQ = 10σ/S), precision, accuracy and ruggedness. The linear response was obtained using the equation, y = 511.5x+17603 (r2 = 0.9920) and y = 2886x+6821 (r2 = 0.9935) for BA and UA, respectively. The LOD and LOQ were found to be 0.268 ± 0.520 μg mL− 1, 0.878 ± 0.183 μg mL− 1 for BA (0.58% w/w) and 3.140 ± 0.36 μg mL− 1, 8.820 ± 0.85 μg mL− 1 for UA (1.09% w/w), respectively. The %RSD of precision and recovery of BA and UA was < 2.0%. The proposed method was simple, accurate, specific, precise and reproducible.

Metabolism-mediated interaction potential of standardized extract of Tinospora cordifolia through rat and human liver microsomes.

Objective: Tinospora cordifolia is used for treatment of several diseases in Indian system of medicine. In the present study, the inhibition potential of T. cordifolia extracts and its constituent tinosporaside to cause herb-drug interactions through rat and human liver cytochrome enzymes was evaluated. Materials and Methods: Bioactive compound was quantified through reverse phase high-performance liquid chromatography, to standardize the plant extracts and interaction potential of standardized extract. Interaction potential of the test sample was evaluated through cytochrome P450-carbon monoxide complex (CYP450-CO) assay with pooled rat liver microsome. Influence on individual recombinant human liver microsomes such as CYP3A4, CYP2D6, CYP2C9, and CYP1A2 isozymes was analyzed through fluorescence microplate assay, and respective IC50 values were determined. Results: The content of tinosporaside was found to be 1.64% (w/w) in T. cordifolia extract. Concentration-dependent inhibition was observed through T. cordifolia extract. Observed IC50 (μg/ml) value was 136.45 (CYP3A4), 144.37 (CYP2D6), 127.55 (CYP2C9), and 141.82 (CYP1A2). Tinosporaside and extract showed higher IC50 (μg/ml) value than the known inhibitors. T. cordifolia extract showed significantly less interaction potential and indicates that the selected plant has not significant herb-drug interactions relating to the inhibition of major CYP450 isozymes. Conclusions: Plant extract showed significantly higher IC50 value than respective positive inhibitors against CYP3A4, 2D6, 2C9, and 1A2 isozymes. Consumption of T. cordifolia may not cause any adverse effects when consumed along with other xenobiotics.

Validation of Medicinal Herbs for Skin Aging

Skin aging is the result of programed senescence and prolonged environmental injury to skin. Human skin is continuously exposed to environmental influences and is therefore subjected to both intrinsic as well as extrinsic aging processes. Aged skin is characterized by the loss of skin tone and resilience, increased roughness and dryness, irregular pigmentation, sunburn, accelerated skin aging, wrinkles, and several malignant skin cancers. Plant secondary metabolites have been exploited for their potential activities such as antiaging, antiwrinkle, antioxidant, antiinflammatory, wound healing, skin whitening, and anticancer activities. Several scientific validations on natural products derived from the traditional system of medicine have been developed in this context. Recent trends in antiaging research projected the use of natural products derived from ancient era after scientific validation. Therefore, an attempt has been made in this chapter to highlight skin aging pathways of natural bioactive molecules and skin aging management.

Paradigm shift in natural product research: traditional medicine inspired approaches

The development of traditional medicine with the perspectives of safety, efficacy and quality would help not only to preserve the traditional heritage but also to rationalize the use of herbal medicine in the human healthcare. Nature is considered as a compendium for templates of new chemical entities. The medicinal plants mentioned in the different ancient texts worldwide may be explored with the modern scientific approaches for better leads in the healthcare. Drugs from medicinal plants are unique for their chemical and biological features, and are gaining global acceptance because they offer natural ways to treat diseases and promote healthcare. Natural products are the best sources of chemical diversity for finding new drugs and leads. Globalization of traditional medicine is necessary for health care with assessment of its safety, efficacy, therapeutic and clinical evidence. Evidence based validation of the ethnopharmacological claims on traditional medicine is necessary for its promotion and development. Applications of techniques such as marker analysis, DNA bar coding, plant metabolomics, network pharmacology etc. are being taken into account for the validation and documentation of medicinal plants. This can be achieved by the scientific exploitation of the established facts from ancient systems through proper validation of the claims based on pharmacological and phytochemical assessments.

Factors to Consider in Development of Nutraceutical and Dietary Supplements

Abstract The development of functional food (medicinal plants, marine sources, vitamins, minerals, fish oils, plant-based oils, amino acids, etc.) as nutraceutical and dietary supplements are gaining momentum with the perspectives of safety, efficacy, and quality for promotion of health of human beings. Nutraceuticals are diet supplements that deliver an enriched, presumed bioactive compound from natural resources, presented in a nonfood matrix, that have additional health or physiological benefits over and above the normal nutritional value and used with the purpose of enhancing human pathophysiological conditions. Due to the rapid expansion in this area several aspects need to be considered that could influence the future of nutraceuticals and dietary supplements. Authentication, quality control, standardization, validation processes, regulatory aspects, clinical risk assessment, customer awareness, and postmarketing surveillance are the key points which could ensure the safety and efficacy of nutraceutical and dietary supplements. Dietary bioactive compounds from different functional foods and nutraceuticals play a major role in improving human health.