The fabrication and assessment of mosquito repellent cream for outdoor protection.

Mosquito-borne infections like dengue, malaria, chikungunya, etc. are a nuisance and can cause profound discomfort to people. Due to the objectional side effects and toxicity associated with synthetic pyrethroids, N,N-diethyl-3-methylbenzamide (DEET), N,N-diethyl phenylacetamide (DEPA), and N,N-di ethyl benzamide (DEBA) based mosquito repellent products, we developed an essential oil (EO) based mosquito repellent cream (EO-MRC) using clove, citronella and lemongrass oil. Subsequently, a formulation characterization, bio-efficacy, and safety study of EO-MRC were carried out. Expression of Anti-OBP2A and TRPV1 proteins on mosquito head parts were studied by western blotting. In-silico screening was also conducted for the specific proteins. An FT-IR study confirmed the chemical compatibility of the EOs and excipients used in EO-MRC. The thermal behaviour of the best EOs and their mixture was characterized by thermogravimetric analysis (TGA). GC-MS examination revealed various chemical components present in EOs. Efficacy of EO-MRC was correlated with 12% N,N-diethyl benzamide (DEBA) based marketed cream (DBMC). Complete protection time (CPT) of EO-MRC was determined as 228 min. Cytotoxicity study on L-132 cell line confirmed the non-toxic nature of EO-MRC upon inhalation. Acute dermal irritation study, acute dermal dose toxicity study, and acute eye irritation study revealed the non-toxic nature of EO-MRC. Non-target toxicity study on Danio rerio confirmed EO-MRC as safer for aquatic non-target animals. A decrease in the concentration of acetylcholinesterase (AChE) was observed in transfluthrin (TNSF) exposed Wistar rats. While EO-MRC did not alter the AChE concentrations in the exposed animals. Results from western blotting confirmed that Anti-OBP2A and TRPV1 proteins were inhibited in TNSF exposed mosquitoes. Mosquitoes exposed to EO-MRC showed a similar expression pattern for Anti-OBP2A and TRPV1 as the control group. In silico study revealed eight identified compounds of the EOs play significant roles in the overall repellency property of the developed product. The study emphasizes the mosquito repellent activity of EO-MRC, which could be an effective, eco-friendly, and safer alternative to the existing synthetic repellents for personal protection against mosquitoes during field conditions.

Topical Delivery of Geranium/Calendula Essential Oil-Entrapped Ethanolic Lipid Vesicular Cream to Combat Skin Aging.

The present study deals with the evaluation of the age-defying potential of topical cream formulations bearing Geranium essential oil/Calendula essential oil-entrapped ethanolic lipid vesicles (ELVs). Two types of cream formulations were prepared, viz., conventional and ELVs spiked o/w creams. Essential oil- (EO-) loaded ELVs were characterized by vesicle size, polydispersity index, encapsulation efficiency, and scanning electron microscopy. The cream formulations were evaluated for homogeneity, spreadability, viscosity, pH, in vitro antioxidant capacity, sun protection factor, and in vitro collagenase and elastase inhibition capacity. Confocal laser scanning microscopy (CLSM) was performed to ascertain skin permeation of conventional and vesicular cream. The results of in vitro antioxidant studies showed that GEO-/CEO-loaded vesicular creams have notable antioxidant capacity when compared to nonvesicular creams. GEO- or CEO-loaded vesicular creams exhibited the highest SPF value 10.26 and 18.54, respectively. Both the EO-based vesicular creams showed in vitro collagenase and elastase enzyme inhibition capacity. CLSM images clearly depicted that vesicular cream deep into the skin layers. From the research findings, the age-defying potential and photoprotective effects of GEO and CEO were confirmed. It can be concluded that ELVs are able to preserve the efficiency of EOs and have the potential to combat skin aging.

Permeation, stability and acute dermal irritation of miroestrol and deoxymiroestrol from Pueraria candollei var. mirifica crude extract loaded transdermal gels.

In this study, permeation behaviors and chemical stability of miroestrol and deoxymiroestrol from Pueraria candollei var. mirifica (PM), Thai traditional medicine, crude extract containing transdermal gels were firstly evaluated. Three different PM extract containing gels were formulated, including hydroalcoholic and microemulsion gels using carbomer, and silicone gel using silicone elastomer. In vitro permeation through porcine ear skin demonstrated that the flux and 24 h cumulative permeation of miroestrol and deoxymiroestrol were in the order of hydroalcoholic > silicone > microemulsion gels. Hydroalcoholic gel provided the highest partition coefficient from gel onto skin, and thus the skin permeability coefficient. After 24 h permeation, no miroestrol and deoxymiroestrol remained deposited in the skin. Accelerated study using heating-cooling revealed insignificant difference between the remaining percentages of miroestrol and deoxymiroestrol in aqueous and non-aqueous based gels. Long-term stability study showed that miroestrol contents remained constant for 90 d and 30 d under 5 ± 3 °C and 30 ± 2 °C, 75 ± 5%RH, respectively; whereas the percentage of deoxymiroestrol decreased significantly after 30 d storage, irrespective of storage conditions. Acute dermal irritation test on New Zealand White rabbits showed that PM hydroalcoholic gels were non-irritant, with no signs of erythema or oedema.[Figure: see text].

Tandem mass spectrometry of aqueous extract from Ficus dubia sap and its cell-based assessments for use as a skin antioxidant.

Since 2006, Ficus dubia has been reported as a new Ficus species in Thailand. As per our recent report, the red-brown aqueous extract of F. dubia sap (FDS) has been determined to strongly exhibit in vitro anti-radicals. However, the phytochemicals in the FDS extract related to health-promoting antioxidation have not been explored. Thus, in this study, we aimed to investigate the chemical components of the F. dubia sap extract by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-MS/QTOF-MS) and its potential use in cosmetics in terms of cellular antioxidation on keratinocytes (HaCaT), phototoxicity, and irritation on 3D skin cell models following standard tests suggested by the Organization for Economic Cooperation and Development (OECD). It was found that the sap extract was composed of quinic acid and caffeoyl derivatives (e.g., syringoylquinic acid, 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, and dimeric forms of caffeoylquinic acids). The extract has significantly exhibited antioxidant activity against H2O2-induced oxidative stress in HaCaT cells. The cellular antioxidative effect of the FDS extract was remarkably dependent on the presence of 3- and 4-O-caffeoylquinic acid in the extract. Furthermore, the FDS extract showed negative results on skin phototoxicity and irritation. Overall, the results reveal that the FDS extract could be developed as a new antioxidant candidate for a skin healthcare product.

Lidocaine-loaded reduced graphene oxide hydrogel for prolongation of effects of local anesthesia: In vitro and in vivo analyses.

Lidocaine is widely used as a local anesthetic for alleviation of post-operative pain and for management of acute and chronic painful conditions. Although several approaches are currently used to prolong the duration of action, an effective strategy to achieve neural blockage for several hours remains to be identified. In this study, a lidocaine-loaded Pluronic® F68-reduced graphene oxide hydrogel was developed to achieve sustained release of lidocaine. Fourier transform infrared spectroscopy, X-ray diffraction, and Raman spectroscopy confirmed the synthesis of Pluronic® F68-reduced graphene oxide. Transmission electron microscopy showed wrinkled, flat nanosheets with micelles attached. The developed hydrogel showed desirable pH, viscosity, adhesiveness, hardness, and cohesiveness for topical application. The ex vivo release study demonstrated the ability of the Pluronic® F68-reduced graphene oxide hydrogel to prolong release up to 10 h, owing to the strong π-π interactions between the graphene oxide and the lidocaine. In comparison with a commercial lidocaine ointment, the developed graphene oxide hydrogel showed sustained anesthetic effect in the radiant heat tail flick test and sciatic nerve block model. Thus, this study demonstrates the potential of using Pluronic® F68-reduced graphene oxide nanocarriers to realize prolonged effects of local anesthesia for effective pain management.

Anti-melanogenic effects of hot-water extracts from Torreya nucifera via MAPKs and cAMP signaling pathway on B16F10 cells.

Torreya nucifera is an evergreen tree in the family Taxaceae, the seeds, leaves, and stems of which have long been used as edible products and herbal medicines in Korea. Previous studies of biological activity have shown that T. nucifera has antioxidant and anti-inflammatory effects. However, the effect of T. nucifera leaves on melanogenesis are yet to be studied. In this investigation, we used B16F10 melanoma cells to test the efficacy of T. nucifera leaf hot water extract (TLWE). α-melanocyte stimulating hormone (α-MSH) stimulated B16F10 melanoma cells were treated with various concentrations of TLWE (50, 100, and 200 µg/mL). The results showed that TLWE reduced the melanin content and cellular tyrosinase activity in a concentration-dependent manner. It also inhibited the phosphorylation of p38 mitogen-activated protein kinase (p38) and c-Jun N-terminal kinase (JNK) in the mitogen-activated protein kinase (MAPK) signaling pathway. The compounds catechin and ρ-coumaric acid, which are known to have a whitening effect on skin, were detected by HPLC analysis. These results suggest that TLWE has an anti-melanogenic effect. In addition, the safety of TLWE was tested. The results of the skin irritation test showed that TLWE is harmless to the human skin, even at higher concentrations than those used in the experiment. Therefore, we suggest that the water extract of T. nucifera leaves has potential for use as a skin-whitening agent.

Evaluation of skin irritation following weathered crude oil exposure in two mouse strains.

Petroleum crude oil spills are common and vary in size and scope. Spill response workers throughout the course of remediation are exposed to so-called weathered oil and are known to report diverse health effects, including contact dermatitis. A murine model of repeated exposure to weathered marine crude oil was employed utilizing two strains of mice, C57BL/6 and BALB/c, to investigate the pathology of this irritant and identify the principal hydrocarbon components deposited in skin. Histopathology demonstrated clear signs of irritation in oil-exposed skin from both mouse strains, characterized by prominent epidermal hyperplasia (acanthosis). BALB/c mice exposed to oil demonstrated more pronounced irritation compared with C57BL/6 mice, which was characterized by increased acanthosis as well as increased inflammatory cytokine/chemokine protein expression of IL-1ß, IL-6, CXCL10, CCL2, CCL3, CCL4, and CCL11. A gas chromatography/mass spectrometry method was developed for the identification and quantification of 42 aliphatic and EPA priority aromatic hydrocarbons from full thickness skin samples of C57BL/6 and BALB/c mice exposed to oil samples. Aromatic hydrocarbons were not detected in skin; however, aliphatic hydrocarbons in skin tended to accumulate with carbon numbers greater than C16. These preliminary data and observations suggest that weathered crude oil is a skin irritant and this may be related to specific hydrocarbon components, although immune phenotype appears to impact skin response as well.

Self-Assembled Lecithin/Chitosan Nanoparticles Based on Phospholipid Complex: A Feasible Strategy to Improve Entrapment Efficiency and Transdermal Delivery of Poorly Lipophilic Drug.

PURPOSE: Lecithin/chitosan nanoparticles have shown great promise in the transdermal delivery of therapeutic agents. Baicalein, a natural bioactive flavonoid, possesses multiple biological activities against dermatosis. However, its topical application is limited due to its inherently poor hydrophilicity and lipophilicity. In this study, the baicalein-phospholipid complex was prepared to enhance the lipophilicity of baicalein and then lecithin/chitosan nanoparticles loaded with the baicalein-phospholipid complex were developed to improve the transdermal retention and permeability of baicalein. METHODS: Lecithin/chitosan nanoparticles were prepared by the solvent-injection method and characterized in terms of particle size distribution, zeta potential, and morphology. The in vitro release, the ex vivo and in vivo permeation studies, and safety evaluation of lecithin/chitosan nanoparticles were performed to evaluate the effectiveness in enhancing transdermal retention and permeability of baicalein. RESULTS: The lecithin/chitosan nanoparticles obtained by the self-assembled interaction of chitosan and lecithin not only efficiently encapsulated the drug with high entrapment efficiency (84.5%) but also provided sustained release of baicalein without initial burst release. Importantly, analysis of the permeation profile ex vivo and in vivo demonstrated that lecithin/chitosan nanoparticles prolonged the retention of baicalein in the skin and efficiently penetrated the barrier of stratum corneum without displaying skin irritation. CONCLUSION: These results indicate the potential of drug-phospholipid complexes in enhancing the entrapment efficiency and self-assembled lecithin/chitosan nanoparticles based on phospholipid complexes in the design of a rational transdermal delivery platform to improve the efficiency of transdermal therapy by enhancing its percutaneous retention and penetration in the skin.

Novel Clove Essential Oil Nanoemulgel Tailored by Taguchi's Model and Scaffold-Based Nanofibers: Phytopharmaceuticals with Promising Potential as Cyclooxygenase-2 Inhibitors in External Inflammation.

PURPOSE: Clove essential oil is a phytochemical possessing a vast array of biological activities. Nevertheless, fabricating nano topical delivery systems targeted to augment the anti-inflammatory activity of the oil has not been investigated so far. Accordingly, in this study, controlled release nanoparticulate systems, namely nanoemulgel and nanofibers (NFs), of the oil were developed to achieve such goal. METHODS: The nanoemulsion was incorporated in the hydrogel matrix of mixed biopolymers - chitosan, guar gum and gum acacia - to formulate nanoemulsion-based nanoemulgel. Taguchi's model was adopted to evaluate the effect of independently controlled parameters, namely, the concentration of chitosan (X1), guar gum (X2), and gum acacia (X3) on different dependently measured parameters. Additionally, the nanoemulsion-based NFs were prepared by the electrospinning technique using polyvinyl alcohol (PVA) polymer. Extensive in vitro, ex vivo and in vivo evaluations of the aforementioned formulae were conducted. RESULTS: Both Fourier transform-infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) established the complete dispersion of the nanoemulsion in the polymeric matrices of the prepared nanoemulgel and NFs. The ex vivo skin permeation data of clove essential oil from the prepared formulations showed that NFs can sustain its penetration through the skin comparably with nanoemulgel. Topical treatment with NFs (once application) and nanoemulgel (twice application) evoked a marvelous in vivo anti-inflammatory activity against croton oil-induced mouse skin inflammation model when compared with pure clove essential oil along with relatively higher efficacy of medicated NFs than that of medicated nanoemulgel. Such prominent anti-inflammatory activity was affirmed by histopathological and immunohistochemical examinations. CONCLUSION: These results indicated that nanoemulsion-based nanoemulgel and nanoemulsion-based NFs could be introduced to the phytomedicine field as promising topical delivery systems for effective treatment of inflammatory diseases instead of nonsteroidal anti-inflammatory drugs that possess adverse effects.

Potential application of novel liquid crystal nanoparticles of isostearyl glyceryl ether for transdermal delivery of 4-biphenyl acetic acid.

Novel liquid crystal nanoparticles (LCNs) composed of isostearyl glyceryl ether (GE-IS) and ethoxylated hydrogenated castor oil (HCO-60) were developed for the enhanced transdermal delivery of 4-biphenyl acetic acid (BAA). The physical properties and pharmaceutical properties of the LCNs were measured. The interaction between the intercellular lipid model of the stratum corneum and the LCNs was observed to elucidate the skin permeation mechanism. In the formulation, the LCNs form niosomes with mean particles sizes of 180-300 nm. The skin absorption mechanisms of LCNs are different, depending upon the application and buffer concentration. The LCNs composed of GE-IS and HCO-60 are attractive tools for use as transdermal drug delivery systems carriers for medicines and cosmetics, due to their high efficiency and safety.

Evaluation of moisturizing and irritation potential of sacha inchi oil.

OBJECTIVE: The moisturizing and irritation effects of sacha inchi oil were evaluated. STUDY DESIGN: The moisturizing effect on the skin was clinically assessed using a regression study design. Sacha inchi oil or olive oil (benchmark) was applied on the left or right lower leg of the subjects for 14 days followed by application discontinuation for 2 days. The TEWL, skin moisture content and dryness appearance were observed. METHODS: The fatty acid composition and characteristics of cold-pressed sacha inchi seed oil were determined. Skin tissues cultured ex vivo were used to assess primary irritation induced by the oil by examining keratin 1 expression and TNF-α and IL-1α release from the oil-applied tissues. RESULTS: The sacha inchi oil contained 42.3% linolenic acid and 39.5% linoleic acid. This oil's saponification, iodine, acid and peroxide values were 168.58 ± 1.55 mg KOH/g, 203.00 ± 0.04 g I2 /100 g, 1.68 ± 0.03 mg KOH/g, and 1.95 ± 0.26 mEq peroxide/kg, respectively. Compared with nontreated skin tissues, induced secretion of TNF-α and IL-1α and disruption of keratin 1 integrity in the stratum corneum layer were not found in the sacha inchi oil-treated tissues. In a clinical study with 13 volunteers, the improvement in moisture content and skin dryness appearance at the sacha inchi oil-applied site was comparable with that observed at the olive oil-applied site. CONCLUSIONS: The sacha inchi oil was mild to the skin and benefited dry skin.

Development of topical drug delivery system with Sphaeranthus indicus flower extract and its investigation on skin as a cosmeceutical product.

BACKGROUND: Cosmetics are the products used to beautify the skin. Emulsion is a fine dispersion of two or more immiscible liquids. Sphaeranthus indicus is claimed to be used for skin beautification in folk medicine. Multiple emulsion was formulated containing the extract of S indicus flowers. AIMS: This research study indicates that extract of S indicus flowers contains sufficient amount of polyphenols and also possess good antioxidant activity with mushroom tyrosinase inhibition activity. METHOD: Further, stable multiple emulsion was developed and stability testing was performed for 180 days by keeping the multiple emulsion at 8°C ± 1, 25°C ± 1, 40°C ± 1, and 40°C ± 1 with 75% ± 1 RH. Parameters checked were color change, phase distribution, viscosity, droplet size and size distribution, pH determination, and electrical conductivity. Sun protection factor (SPF) was determined which also showed promising results. Skin testing on human volunteers was done for 3 months after biosafety profiling of the most stable multiple emulsion. RESULTS: This also showed remarkable effects. Skin erythema, melanin, and sebum were reduced. Skin hydration and elasticity were increased. There was also reduction in the number of skin large and small skin pores. Skin spot area was also reduced by the use of multiple emulsion loaded with S indicus flower extract. ANOVA test showed that all the effects produced on skin were significant, ie, P ≤ .05. CONCLUSION: A stable multiple emulsion was developed which produced significant cosmetic effects on human skin.

Lidocaine tripotassium phosphate complex laden microemulsion for prolonged local anaesthesia: In vitro and in vivo studies.

Lidocaine is widely used as a local anaesthetic in the clinical practice to manage pre- and post-operative pain, skin burns, etc. However, the short duration of action (< 2 h) of marketed dosage forms limit their ability to meet clinical needs. Herein, we prepared a lidocaine-tPP(tri potassium phosphate)-complex loaded microemulsion to achieve greater penetration, followed by destabilization of microemulsion in the skin layer to precipitate oil-complex to produce a depot effect in the skin for prolonging the effects of anaesthesia. The lidocaine-tPP-complex-microemulsion was compared with lidocaine base loaded microemulsion, marketed ointment USP and lidocaine HCl. The pseudo ternary phase diagrams at three Smix ratios (1:2, 1:3 and 1:4; Pluronic F127: PEG 400) were constructed using Capmul MCM C8 EP as oil phase. The Smix at 1:4 ratio showed large microemulsion area in comparison to 1:2 and 1:6 ratio. The lidocaine base (LD-1:4-ME10O45SM and LD-1:4-ME20O45SM) and lidocaine-tPP-complex (LDC-1:4-ME10O45SM and LDC-1:4-ME20O45SM) loaded microemulsion batches (1:4 ratio) were thermodynamically stable. The ex vivo diffusion study showed sustained release up to 12 h with microemulsion batches, in comparison to lidocaine HCl (4 h) and ointment base (7 h). The selected LDC-1:4-ME20O45SM batch was non-irritating on the rabbit skin. In drug retention studies, LD-1:4-ME20O45SM and LDC-1:4-ME20O45SM batches showed 2.68- and 3.93-fold greater lidocaine retention in comparison to ointment USP. The radiant heat tail-flick test showed prolong local anaesthesia using LDC-1:4-ME20O45SM in comparison to ointment USP. The findings suggest that lidocaine-tPP-complex loaded microemulsion could be a potential strategy for providing prolong local anaesthesia.

Development of Novel Topical Cosmeceutical Formulations from Nigella sativa L. with Antimicrobial Activity against Acne-Causing Microorganisms.

Acne vulgaris occurs due to the inflammation of sebaceous follicles in the skin. It is triggered by the activity of some bacterial species like Propionibacterium acnes, Staphylococcus aureus, and Staphylococcus epidermidis. Acquisition of antibiotic resistance by these microorganisms and adverse effects associated with the current treatment regimens necessitate the introduction of novel therapeutic agents for acne vulgaris. Thus, this study was undertaken to develop novel gel formulations from seeds of Nigella sativa L. and to evaluate the antibacterial potential against some acne-causing bacterial species. The antibacterial activity of seed extracts was initially screened against S. aureus and P. acnes by the agar well diffusion method. Thereafter, topical gels were formulated incorporating the ethyl acetate extract of seeds of N. sativa at three different concentrations. These topical formulations were subjected to antimicrobial activity studies while the stability was evaluated over a period of 30 days. All three formulations were capable of inhibiting the growth of S. aureus and P. acnes, with the highest antibacterial activity in the formulation comprising 15% of the seed extract. Interestingly, the antibacterial potency of this formulation against S. aureus surpassed the commercial synthetic product used as the positive control. Moreover, any alteration in color, odor, homogeneity, washability, consistency, and pH was not observed while the antibacterial potency was also retained during the storage period. The potent antibacterial activity in topical gel formulations developed from the ethyl acetate extract of N. sativa signposts their suitability as alternatives to existing antiacne agents in the management of acne vulgaris.

Characterization of the in vitro, ex vivo, and in vivo Efficacy of the Antimicrobial Peptide DPK-060 Used for Topical Treatment.

Antimicrobial peptides, also known as host defense peptides, have recently emerged as a promising new category of therapeutic agents for the treatment of infectious diseases. This study evaluated the preclinical in vitro, ex vivo, and in vivo antimicrobial activity, as well as the potential to cause skin irritation, of human kininogen-derived antimicrobial peptide DPK-060 in different formulations designed for topical delivery. We found that DPK-060 formulated in acetate buffer or poloxamer gel caused a marked reduction of bacterial counts of Staphylococcus aureus in vitro (minimum microbicidal concentration <5 µg/ml). We also found that DPK-060 in poloxamer gel significantly suppressed microbial survival in an ex vivo wound infection model using pig skin and in an in vivo mouse model of surgical site infection (≥99 or ≥94% reduction in bacterial counts was achieved with 1% DPK-060 at 4 h post-treatment, respectively). Encapsulation of DPK-060 in different types of lipid nanocapsules or cubosomes did not improve the bactericidal potential of the peptide under the applied test conditions. No reduction in cell viability was observed in response to administration of DPK-060 in any of the formulations tested. In conclusion, the present study confirms that DPK-060 has the potential to be an effective and safe drug candidate for the topical treatment of microbial infections; however, adsorption of the peptide to nanocarriers failed to show any additional benefits.

In situ hexagonal liquid crystal for intra-articular delivery of sinomenine hydrochloride.

The aim of this study was to investigate the release behaviors of sinomenine hydrochloride loaded via in situ hexagonal liquid crystal (ISH), and its potential to improve the local bioavailability in knee joints of sinomenine hydrochloride (SMH) after intra-articular administration. The ISH was prepared by a liquid precursor mixture containing phytantriol (PT), Vitamin E acetate (VEA), ethanol (ET), and water. The in vitro release profiles revealed a sustained release of SMH from the optimized ISH formula (PT/VEA/ET/water, 60.8:3.2:16.0:20.0, w/w/w/w), which was selected for the in vivo pharmacokinetics and preliminary pharmacodynamics studies. In both healthy and adjuvant-induced arthritis (AA) rats, the SMH loaded ISH showed significantly smaller SMH AUC0-∞ in plasma (P < 0.01), and higher SMH concentration in synoviums (2˜168 h) than that of SMH solution, indicating that the ISH significantly reduced the leakage of SMH into systemic circulation. The t1/2α of SMH loaded ISH in the knee joints of AA rats, was longer (13.42 h) than that of healthy rats (1.34 h) (P < 0.05), most likely that in vivo drug release behavior of SMH loaded ISH was affected by the physiological environment of the joint. It was found that the SMH loaded ISH could benefit AA-rats by suppressing the level of IL-1ß in comparison to SMH solutions. The results of the histopathology of knee joints in AA rats displayed that the SMH loaded ISH might be suitable for the development of treatment strategies for rheumatoid arthritis diseases.

Study of the potential adverse effects caused by the dermal application of Dillenia indica L. fruit extract standardized to betulinic acid in rodents.

This study aimed to evaluate the potential adverse effects of the dermal administration of Dillenia indica Linnaeus (D. indica) fruit extract in healthy rodents; the extract was standardized to betulinic acid. In the initial phase, the acute effects were evaluated on the skin application site of a single extract dose. A skin irritation test was performed in male Wistar rats (n = 8/group) receiving the extract (50-150 mg/mL) with betulinic acid (0.5-1.5%, respectively). A photosensitivity test was performed in male BALB/c mice (n = 6/group) receiving the extract (150 mg/mL). Afterwards, other BALB/c mice (n = 20, male:female, 1:1) were used to assess the systemic alterations caused by 14 daily repeated doses (150 mg/mL) by monitoring the effects on mortality, body morphology, behavior, nutrition status, neuromotor reactions, organ morphology and weight, and blood tests. At this time, 0.5 mg/mL clobetasol was used as the positive control. The skin irritation index suggested that negligible skin irritation had occurred, even when the extract was applied to the rat skin at 150 mg/mL. However, the extract acted as a photosensitizer on mouse skin, showing a photosensitizing activity close to that of 10 mg/mL 5-methoxypsoralen. Repeated doses caused no mouse mortality, aggressiveness, piloerection, diarrhea, convulsions, neuromotor alterations or nutrition status changes. The mouse organ weights did not change, and the mice did not have alterations in their blood compositions. Clobetasol caused a reduction in the mononuclear leukocyte numbers. In general, the data suggest that the extract was safe in healthy rodents but indicate that caution should be taken with the photosensitizing activity; in addition, this activity should be further explored as it may be useful for phototherapeutic drug development.

Formulation, characterization and in vivo evaluation of Hedera helix L., topical dosage forms.

The purpose of this study was to prepare topical formulations of micro emulsion, gel and ointment containing the Hedera helix L. extracts against asthma and to evaluate the physicochemical characteristics. A validated HPLC method was used for the analysis of blood plasma. In-vivo studies of the drugs were compared in rabbit plasma with oral dosing. Stability studies were performed for 3 months. The results showed that formulations were stable. No Skin irritation observed on rabbits. The optimized micro emulsion and gel showed fast absorption. Maximal plasma concentration (cmax) and the maximal time to reach cmax (tmax) were 70.226µg/mL, 75.26µg/mL and 2 hours for the micro emulsion and gel, 90.11µg/mL and 1 hour for the oral drug syrup respectively. Pharmacokinetic parameters such as tmax, cmax and AUC of the selected formulations and oral dosing were significantly different (P < 0.01).

Annona muricata extract containing pharmaceutical emulgels with and without penetration enhancer for depigmenting and antierythmic effects.

The basic purpose of this research work was to investigate the skin depigmenting and antierythmetic effects of emulgel containing Annona muricata L. fruit extract by comparing it with its control and the variation in these effects with the addition of penetration enhancer. The control (without extract and penetration enhancer i.e. clove oil 8%) and the two test formulations with 4% fruit extract FA and FB (without clove oil and with clove oil) were formulated and evaluated for in vitro characteristics (pH, conductivity and in vitro release). The emulgels were then applied on the cheeks of 26 healthy female human volunteers (n=26) for a study period of 12 weeks. Skin melanin and erythema contents were measured by Mexameter at base line and then after every 2 weeks. Both the test formulations showed significant decrease in melanin and erythema contents when compared to control but FB showed marked decrease in skin melanin when compared to the FA. While in case of skin erythema, the effects of FA were greater as compared to other formulation. When paired sample t test (5% level of significance) was applied, the test formulations showed significant results. This study reveals that the Annona muricata L. fruit extract naturally contains some important phenolic compounds and can be effectively used in topical preparations for the treatment of skin hyperpigmentation and dermatitis. Skin whitening effects can be increased by the addition of penetration enhancer.

Development of an effective and safe topical anti-inflammatory gel containing Jatropha gossypiifolia leaf extract: Results from a pre-clinical trial in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha gossypiifolia L. (Euphorbiaceae) is a medicinal plant widely used in traditional medicine as an anti-inflammatory remedy. The topical use of the leaves and/or aerial parts of this plant as anti-inflammatory, analgesic, wound healing and anti-infective in several skin diseases is a common practice in many countries. The use of baths or dressings with this vegetal species is frequently reported in folk medicine. AIM OF THE STUDY: To evaluate the topical anti-inflammatory of aqueous extract from leaves of J. gossypiifolia and to develop a safe and effective herbal gel with anti-inflammatory potential. MATERIAL AND METHODS: First, the topical acute anti-inflammatory activity of J. gossypiifolia extract was evaluated in ear edema induced by single application of croton oil in mice. Then, a polaxamer-based gel containing J. gossypiifolia extract was developed, physicochemically characterized and evaluated in the same model of inflammation to assess whether the extract incorporation in gel would affect its anti-inflammatory potential. The best formulation was then assayed in ear edema induced by multiple applications of croton oil in mice, to evaluate its chronic anti-inflammatory potential. Inflammatory parameters evaluated included edema, nitrite concentration, mieloperoxidase (MPO) activity and oxidative damage in lipids and proteins. Finally, dermal irritation/corrosion test in mice was performed to access the safeness of the developed gel. Phytochemical characterization of J. gossypiifolia extract was performed by high performance liquid chromatography with diode array detector (HPLC-DAD) analysis. RESULTS: J. gossypiifolia showed significant acute anti-inflammatory activity in ear edema model, and this activity was significantly increased when equivalent amounts of extract was applied incorporated in the developed polaxamer gels. The gels containing different amounts of extract reduced significantly the levels of edema, nitrite and MPO enzyme in mice ears, with intensity similar to the anti-inflammatory standard drug dexamethasone. The gel containing 1.0% of extract was further evaluated and also showed significant anti-inflammatory activity in chronic inflammation test, reducing significantly ear edema, lipid peroxidation and depletion of reduced glutathione, similarly to dexamethasone. Placebo formulation as well as gel containing extract showed pH compatible to that of human skin and exhibited absence of signs of toxicity in mice, indicating the safeness of the developed product for topical use. HPLC analysis confirmed the presence of C-glycosylflavonoids (orientin, isoorientin, vitexin and isovitexin) as the major compounds of J. gossypiifolia aqueous leaf extract. CONCLUSIONS: The results demonstrate the potentiality of J. gossypiifolia gel as a promising safe and effective topical anti-inflammatory agent for treatment of cutaneous inflammatory diseases.