An exploratory study on the effect of mechanical stress on particle formation in monoclonal antibody infusions.

Monoclonal antibody infusions (mAb-i) are administered for the treatment of various diseases. They are often transported over long distances from the compounding site to the site of administration. However, transport studies are typically carried out with the original drug product but not with compounded mAb-i. To address this gap, the impact of mechanical stress on the formation of subvisible/nanoparticles in mAb-i was investigated by dynamic light scattering and flow imaging microscopy. Different mAb-i concentrations were subjected to vibrational orbital shaking and stored at 2-8°C up to 35 days. The screening revealed that pembrolizumab and bevacizumab infusions show the highest propensity for particle formation. Especially bevacizumab at low concentrations exhibited an increase in particle formation. Because of the unknown health risks associated with the long-term application of subvisible particles (SVPs)/nanoparticles in infusion bags, stability studies carried out in the frame of licensing application procedures should also focus on SVP formation in mAb-i. In general, pharmacists should minimize the time of storage and mechanical stress during transport, especially in the case of low-concentrated mAb-i. Moreover, if siliconized syringes are used, they should be washed once with saline solution to minimize particle entry.

Efficient Extraction of Pyrrolizidine Alkaloids from Plants by Pressurised Liquid Extraction - A Preliminary Study.

Pyrrolizidine alkaloids and their corresponding pyrrolizidine alkaloid-N-oxides are secondary plant constituents that became the subject of public concern due to their hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. In contrast to the well-established analytical separation and detection methods, only a few studies have investigated the extraction of pyrrolizidine alkaloids/pyrrolizidine alkaloid-N-oxides from plant material. In this study, we have applied pressurized liquid extraction with the aim of evaluating the effect of various parameters on the recovery of pyrrolizidine alkaloids. The nature of the modifier (various acids, NH3) added to the aqueous extraction solvent, its concentration (1 or 5%), and the temperature (50 - 125 °C) were systematically varied. To analyse a wide range of structurally different pyrrolizidine alkaloids, Jacobaea vulgaris (syn. Senecio jacobaea), Tussilago farfara, and Symphytum officinale were included. Pyrrolizidine alkaloids were quantified by HPLC-MS/MS and the results obtained by pressurised liquid extraction were compared with the amount of pyrrolizidine alkaloids determined by an official reference method. Using this approach, increased rates of recovery were obtained for J. vulgaris (up to 174.4%), T. farfara (up to 156.5%), and S. officinale (up to 288.7%). Hence, pressurised liquid extraction was found to be a promising strategy for the complete and automated extraction of pyrrolizidine alkaloids, which could advantageously replace other time- and solvent-consuming extraction methods.

Development of a Selective Adsorbing Material for Binding of Pyrrolizidine Alkaloids in Herbal Extracts, Based on Molecular Group Imprinting.

Pyrrolizidine alkaloids are secondary plant constituents that became a subject of public concern because of their hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. Due to disregardful harvesting and/or contamination with pyrrolizidine alkaloid-containing plants, there is a high risk of ingesting these substances with plant extracts or natural products. The limit for the daily intake was set to 0.007 µg/kg body weight. If contained in an extract, cleanup methods may help to minimize the pyrrolizidine alkaloid concentration. For this purpose, a material for depleting pyrrolizidine alkaloids in herbal preparations was developed based on the approach of molecular imprinting using monocrotaline. Molecular imprinted polymers are substances with specific binding characteristics, depending on the template used for imprinting. By means of group imprinting, only one molecule is used for creating selective cavities for many molecular pyrrolizidine alkaloid variations. Design of Experiment was used for the development using a 25 screening plan resulting in 64 polymers (32 MIPs/32 NIPs). Rebinding trials revealed that the developed material can compete with common cation exchangers and is more suitable for depleting pyrrolizidine alkaloids than C18- material. Matrix trials using an extract from Chelidonium majus show that there is sufficient binding capacity for pyrrolizidine alkaloids (80%), but the material is lacking in selectivity towards pyrrolizidine alkaloids in the presence of other alkaloids with similar functional groups such as berberine, chelidonine, and coptisine. Beyond this interaction, the selectivity could be proven for other structurally different compounds on the example of chelidonic acid.

Do We Need Plant Food Supplements? A Critical Examination of Quality, Safety, Efficacy, and Necessity for a New Regulatory Framework.

Given the expanding market of plant food supplements (PFSs) not undergoing any pre-marketing authorization, the overall quality, safety and efficacy of PFSs were subjected to a critical examination. Although many high-quality PFSs exist on the legal market, quality concerns are in general justified. Besides economic adulteration, active ingredients dramatically differing from label claims and among products were reported in several studies. In addition, PFSs sold via the Internet may be intentionally adulterated with undeclared prescription drugs. Compared to PFSs with only one single herb, PFSs containing herbal mixtures were more involved in moderate and severe clinical courses. Although prohibited by regulation, misleading labels on PFSs are common. Above all, only vague evidence for the efficacy of PFSs exists. Notwithstanding the unproven efficacy and insufficient safety assessment, PFSs represent a relevant source for consumers to get access to herbal preparations in the United States and meanwhile also in Europe, as launching of licensed/registered European herbal medicinal products (HMPs) has steadily decreased. However, being non-vitamin, non-mineral products, PFSs are neither food nor drugs. In terms of protecting public health and providing the consumer with high-quality, effective, and safe PFSs, possibilities are shown how to deal with the many challenges of PFSs. Last but not least, suggestions are made for assigning PFSs a separate regulatory category being less regulated compared to HMPs but more strictly regulated compared to food laws including implementation of good manufacturing practices and a scientific pre-marketing review process by an expert commission.

Transepithelial Transport of Curcumin in Caco-2 Cells Is significantly Enhanced by Micellar Solubilisation.

Curcumin, the active constituent of Curcuma longa L. (family Zingiberaceae), has gained increasing interest because of its anti-cancer, anti-inflammatory, anti-diabetic, and anti-rheumatic properties associated with good tolerability and safety up to very high doses of 12 g. Nanoscaled micellar formulations on the base of Tween 80 represent a promising strategy to overcome its low oral bioavailability. We therefore aimed to investigate the uptake and transepithelial transport of native curcumin (CUR) vs. a nanoscaled micellar formulation (Sol-CUR) in a Caco-2 cell model. Sol-CUR afforded a higher flux than CUR (39.23 vs. 4.98 µg min-1 cm-2, respectively). This resulted in a higher Papp value of 2.11 × 10-6 cm/s for Sol-CUR compared to a Papp value of 0.56 × 10-6 cm/s for CUR. Accordingly a nearly 9.5 fold higher amount of curcumin was detected on the basolateral side at the end of the transport experiments after 180 min with Sol-CUR compared to CUR. The determined 3.8-fold improvement in the permeability of curcumin is in agreement with an up to 185-fold increase in the AUC of curcumin observed in humans following the oral administration of the nanoscaled micellar formulation compared to native curcumin. The present study demonstrates that the enhanced oral bioavailability of micellar curcumin formulations is likely a result of enhanced absorption into and increased transport through small intestinal epithelial cells.

Survey on the Quality of the Top-Selling European and American Botanical Dietary Supplements Containing Boswellic Acids.

In consideration of the increasing popularity of frankincense and the widely published quality problems associated with botanical dietary supplements, a survey was conducted for the first time on the quality of frankincense containing botanical dietary supplements. Six US products representing 78 % of the units sold and 70 % of the market value, and 11 European products representing 30 % of the units sold and 40 % of the market value were tested for their boswellic acid composition profile, label compliance, and claimed health benefits. Special focus was also set on the statements made with regard to the frankincense applied.Only five products out of seventeen disclosed all relevant information for the Boswellia extract, mentioning the species, the part of plant used, and the boswellic acid content. Whereas all products but one claimed to use Boswellia serrata, three products did not mention the resin as the part applied and 10 products did not declare the boswellic acid content. Apart from the different boswellic acid composition determined with a sensitive LC/MS method, 41 % of the products did not comply with the label declaration. Hence, one product from Italy did not contain any of the six characteristic boswellic acids (KBA, AKBA, αBA, ßBA, AαBA, AßBA) at all and another US product contained only traces, suggesting the absence of frankincense or the use of Boswellia frereana instead of B. serrata. In another product, the ratios of the individual boswellic acids were different from B. serrata gum resin, indicating the use of another species such as Boswellia sacra or Boswellia carterii. Furthermore, two products revealed different boswellic acid contents from those declared on the label. Further, two products did not declare the use of manipulated Boswellia gum resin extract being enriched in acetyl-11-keto-boswellic acid content reaching up to 66 %. In addition, consumers could be misled by outdated literature or references to in vitro studies performed at dosages that can never be achieved in humans following oral administration.In summary, this survey reveals that in spite of increased regulations on botanical dietary supplements, the problem of mislabeling still exists and needs to be addressed by the manufacturers, so that consumers get greater confidence in the botanical dietary supplements they use.

Effect of phospholipid-based formulations of Boswellia serrata extract on the solubility, permeability, and absorption of the individual boswellic acid constituents present.

Boswellia serrata gum resin extracts are used widely for the treatment of inflammatory diseases. However, very low concentrations in the plasma and brain were observed for the boswellic acids (1-6, the active constituents of B. serrata). The present study investigated the effect of phospholipids alone and in combination with common co-surfactants (e.g., Tween 80, vitamin E-TPGS, pluronic f127) on the solubility of 1-6 in physiologically relevant media and on the permeability in the Caco-2 cell model. Because of the high lipophilicity of 1-6, the permeability experiments were adapted to physiological conditions using modified fasted state simulated intestinal fluid as apical (donor) medium and 4% bovine serum albumin in the basolateral (receiver) compartment. A formulation composed of extract/phospholipid/pluronic f127 (1:1:1 w/w/w) increased the solubility of 1-6 up to 54 times compared with the nonformulated extract and exhibited the highest mass net flux in the permeability tests. The oral administration of this formulation to rats (240 mg/kg) resulted in 26 and 14 times higher plasma levels for 11-keto-ß-boswellic acid (1) and acetyl-11-keto-ß-boswellic acid (2), respectively. In the brain, five times higher levels for 2 compared to the nonformulated extract were determined 8 h after oral administration.

Myrtucommulone from Myrtus communis: metabolism, permeability, and systemic exposure in rats.

Nonsteroidal anti-inflammatory drug intake is associated with a high prevalence of gastrointestinal side effects, and severe cardiovascular adverse reactions challenged the initial enthusiasm in cyclooxygenase-2 inhibitors. Recently, it was shown that myrtucommulone, the active ingredient of the Mediterranean shrub Myrtus communis, dually and potently inhibits microsomal prostaglandin E2 synthase-1 and 5-lipoxygenase, suggesting a substantial anti-inflammatory potential. However, one of the most important prerequisites for the anti-inflammatory effects in vivo is sufficient bioavailability of myrtucommulone. Therefore, the present study was aimed to determine the permeability and metabolic stability in vitro as well as the systemic exposure of myrtucommulone in rats. Permeation studies in the Caco-2 model revealed apparent permeability coefficient values of 35.9 ·â€Š10⁻6 cm/s at 37 °C in the apical to basolateral direction, indicating a high absorption of myrtucommulone. In a pilot rat study, average plasma levels of 258.67 ng/mL were reached 1 h after oral administration of 4 mg/kg myrtucommulone. We found that myrtucommulone undergoes extensive phase I metabolism in human and rat liver microsomes, yielding hydroxylated and bihydroxylated as well as demethylated metabolites. Physiologically-based pharmacokinetic modeling of myrtucommulone in the rat revealed rapid and extensive distribution of myrtucommulone in target tissues including plasma, skin, muscle, and brain. As the development of selective microsomal prostaglandin E2 synthase-1 inhibitors represents an interesting alternative strategy to traditional nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors for the treatment of chronic inflammation, the present study encourages further detailed pharmacokinetic investigations on myrtucommulone.

Buchu (Agathosma betulina and A. crenulata): Rightfully Forgotten or Underutilized?

Today, the term buchu refers to the two species in commerce, Agathosma betulina (P.J.Bergius) Pillans and Agathosma crenulata (L.) Pillans (Rutaceae). Its traditional use in urinary tract infections and related ailments made it a popular remedy, specifically in the US, in 19th century, but with the advent of antibiotics it became largely obsolete. Recent focus is on technological use and on the essential oil for use in the perfume and food-flavouring industry. A review of the scarce pharmacological research revealed moderate antimicrobial activity for a leaf extract but not the essential oil of both species in the MIC assay. In the 5-lipoxygenase (5-LO) assay the essential oil of both species revealed IC50 values of 50.37 ± 1.87 µg/ml and 59.15 ± 7.44 µg/ml, respectively. In another study 98% inhibitory activity was determined for 250 µg/ml of an ethanolic extract of A. betulina on cyclooxygenase (COX)-1 and a 25% inhibitory activity on COX-2. Analgesic activity of an ethanolic extract of A. betulina was shown in mice. Moderate antioxidant activity was determined for methanol:dichlormethane extracts of A. betulina and A. crenulata and an aqueous extract of A. betulina showed a Trolox equivalent antioxidant capacity (TEAC) of 11.8 µM Trolox. Recent in vitro studies with a commercial aqueous extract of buchu revealed increased uptake of glucose added to 3T3-L1 cell line, significant inhibition of the respiratory burst of neutrophils and monocytes, reduction in the expression of adhesion molecules and inhibition of the release of IL-6 and TNF-α. In diabetic rats the ingestion of aqueous buchu extract completely normalized the glucose level and in rats receiving a high fat diet the consumption of aqueous buchu extract resulted in less weight gain and less intraperitoneal fat gain as well as reduction of elevated blood pressure to normal associated with cardioprotective effects. Limitations in the hitherto conducted research lie in the undisclosed composition of the buchu extracts used and the difficulty in extrapolating data from animal studies to humans. Health claims for buchu products need to be substantiated by randomized, double-blind and placebo-controlled studies. Only then can they be promoted for their true therapeutic potential.

Short-term study on in-use stability of opened bevacizumab biosimilar PF-06439535 vials.

OBJECTIVES: Aggregation is one of the key critical points limiting the stability of monoclonal antibodies in solution. The present study aimed to investigate the in-use stability of a residual monoclonal antibody solution after withdrawal of most of the filling volume of PF-06439535 (bevacizumab biosimilar), addressing the physical and chemical stability with respect to aggregation and fragmentation. METHODS: The stability of residual PF-06439535 solution (25 mg/mL) after withdrawal of 80% (12.8 mL) filling volume with a 20G needle was monitored over a light-protected storage period of 8 days at 2-8°C and 25°C with measurement time points at D0 (start of storage), D2, D4, and D8 (2, 4, and 8 days of storage after start, respectively). Unopened vials stored under the same conditions served as control. For this purpose, the analytical results from size exclusion chromatography, dynamic light scattering, and micro-flow imaging obtained after the individual measurement time points up to 8 days were compared with those obtained at D0 and with those obtained for unopened vials stored under the same conditions. RESULTS: No aggregation or ongoing fragmentation due to partial withdrawal of filling volume could be observed in the residual PF-06439535 solution. Moreover, no changes in the particle size distribution at D8 compared with the D0 values were identified upon storage at either 2-8°C or 25°C (both opened and unopened vials). The total concentration of particles ≥10 µm of all samples was <100 particles/mL. In addition, no variations in the pH values or in the visual appearance were detected over the whole study period in all samples at all storage conditions. CONCLUSIONS: Consequently, residual PF-06439535 solution (25 mg/mL) in opened vials may be regarded as stable when stored light-protected over a period of 8 days in the refrigerator (2-8°C) or at 25°C.

Best Practice in the chemical characterisation of extracts used in pharmacological and toxicological research-The ConPhyMP-Guidelines.

Background: Research on medicinal plants and extracts derived from them differs from studies performed with single compounds. Extracts obtained from plants, algae, fungi, lichens or animals pose some unique challenges: they are multicomponent mixtures of active, partially active and inactive substances, and the activity is often not exerted on a single target. Their composition varies depending on the method of preparation and the plant materials used. This complexity and variability impact the reproducibility and interpretation of pharmacological, toxicological and clinical research. Objectives: This project develops best practice guidelines to ensure reproducibility and accurate interpretations of studies using medicinal plant extracts. The focus is on herbal extracts used in pharmacological, toxicological, and clinical/intervention research. Specifically, the consensus-based statement focuses on defining requirements for: 1) Describing the plant material/herbal substances, herbal extracts and herbal medicinal products used in these studies, and 2) Conducting and reporting the phytochemical analysis of the plant extracts used in these studies in a reproducible and transparent way. The process and methods: We developed the guidelines through the following process: 1) The distinction between the three main types of extracts (extract types A, B, and C), initially conceptualised by the lead author (MH), led the development of the project as such; 2) A survey among researchers of medicinal plants to gather global perspectives, opportunities, and overarching challenges faced in characterising medicinal plant extracts under different laboratory infrastructures. The survey responses were central to developing the guidelines and were reviewed by the core group; 3) A core group of 9 experts met monthly to develop the guidelines through a Delphi process; and. 4) The final draft guidelines, endorsed by the core group, were also distributed for feedback and approval to an extended advisory group of 20 experts, including many journal editors. Outcome: The primary outcome is the "Consensus statement on the Phytochemical Characterisation of Medicinal Plant extracts" (ConPhyMP) which defines the best practice for reporting the starting plant materials and the chemical methods recommended for defining the chemical compositions of the plant extracts used in such studies. The checklist is intended to be an orientation for authors in medicinal plant research as well as peer reviewers and editors assessing such research for publication.

Boswellia serrata acts on cerebral edema in patients irradiated for brain tumors: a prospective, randomized, placebo-controlled, double-blind pilot trial.

BACKGROUND: Patients irradiated for brain tumors often suffer from cerebral edema and are usually treated with dexamethasone, which has various side effects. To investigate the activity of Boswellia serrata (BS) in radiotherapy-related edema, we conducted a prospective, randomized, placebo-controlled, double-blind, pilot trial. METHODS: Forty-four patients with primary or secondary malignant cerebral tumors were randomly assigned to radiotherapy plus either BS 4200 mg/day or placebo. The volume of cerebral edema in the T2-weighted magnetic resonance imaging (MRI) sequence was analyzed as a primary endpoint. Secondary endpoints were toxicity, cognitive function, quality of life, and the need for antiedematous (dexamethasone) medication. Blood samples were taken to analyze the serum concentration of boswellic acids (AKBA and KBA). RESULTS: Compared with baseline and if measured immediately after the end of radiotherapy and BS/placebo treatment, a reduction of cerebral edema of >75% was found in 60% of patients receiving BS and in 26% of patients receiving placebo (P = .023). These findings may be based on an additional antitumor effect. There were no severe adverse events in either group. In the BS group, 6 patients reported minor gastrointestinal discomfort. BS did not have a significant impact on quality of life or cognitive function. The dexamethasone dose during radiotherapy in both groups was not statistically different. Boswellic acids could be detected in patients' serum. CONCLUSIONS: BS significantly reduced cerebral edema measured by MRI in the study population. BS could potentially be steroid-sparing for patients receiving brain irradiation. Our findings will need to be further validated in larger studies.

Determination of myrtucommulone from Myrtus communis in human and rat plasma by liquid chromatography/tandem mass spectrometry.

Recent studies revealed that the non-prenylated acylphloroglucinol myrtucommulone (MC) from myrtle ( MYRTUS COMMUNIS) potently suppresses the biosynthesis of eicosanoids by direct inhibition of cyclooxygenase-1, microsomal prostaglandin E2 synthase (mPGES)-1, and 5-lipoxygenase at IC50 values in the range of 1 to 29 µM. Moreover, MC showed potent efficacy in animal models of inflammation after intraperitoneal administration. Since the main prerequisite for therapeutic efficacy is sufficient bioavailability, it is important to evaluate whether the concentrations of MC achieved in plasma coincide with the pharmacological active concentrations determined in vitro. For that reason, a sensitive LC/MS/MS method has been developed and validated for the determination of MC in human plasma. This method is based on liquid-liquid extraction of plasma samples with 20 % ethyl acetate in tert-butyl methyl ether using the structurally related acylphloroglucinol hyperforin as the internal standard. Chromatographic separation was achieved on a Gemini C6 Phenyl column using a mixture of acetonitrile/water (85 : 15 v/v) containing 6 mM ammonium formate in a run time of 15 min at a flow rate of 1 mL/min, a column temperature of 40 °C, and an autosampler temperature of 5 °C. Mass spectrometric quantification was carried out in the negative ion mode using electrospray ionization (ESI) and multiple-reaction monitoring (MRM). The most intense [M-H]⁻ MRM transition at m/z 667.4 → m/z 194.9 was used for quantification of MC and the transition at m/z 535.4 to m/z 383.2 was used to monitor hyperforin. The method was linear in the range of 1-100 ng/mL with r > 0.998, an intra- and inter-day RSD of 1.1-8.4 and 7.1-11.8 %, respectively, and a maximum R. E. of 13.8 % at the lowest concentration level. Moreover, cross validation revealed the suitability of the developed LC/MS method for application in rat studies.

Considerations to Be Taken When Carrying Out Medicinal Plant Research-What We Learn from an Insight into the IC50 Values, Bioavailability and Clinical Efficacy of Exemplary Anti-Inflammatory Herbal Components.

Medicinal plants represent a big reservoir for discovering new drugs against all kinds of diseases including inflammation. In spite the large number of promising anti-inflammatory plant extracts and isolated components, research on medicinal plants proves to be very difficult. Based on that background this review aims to provide a summarized insight into the hitherto known pharmacologically active concentrations, bioavailability, and clinical efficacy of boswellic acids, curcumin, quercetin and resveratrol. These examples have in common that the achieved plasma concentrations were found to be often far below the determined IC50 values in vitro. On the other hand demonstrated therapeutic effects suggest a necessity of rethinking our pharmacokinetic understanding. In this light this review discusses the value of plasma levels as pharmacokinetic surrogates in comparison to the more informative value of tissue concentrations. Furthermore the need for new methodological approaches is addressed like the application of combinatorial approaches for identifying and pharmacokinetic investigations of active multi-components. Also the physiological relevance of exemplary in vitro assays and absorption studies in cell-line based models is discussed. All these topics should be ideally considered to avoid inaccurate predictions for the efficacy of herbal components in vivo and to unlock the "black box" of herbal mixtures.

Analysis of Boswellic Acid Contents and Related Pharmacological Activities of Frankincense-Based Remedies That Modulate Inflammation.

Extracts of frankincense, the gum resin of Boswellia species, have been extensively used in traditional folk medicine since ancient times and are still of great interest as promising anti-inflammatory remedies in Western countries. Despite their common therapeutic use and the intensive pharmacological research including studies on active ingredients, modes of action, bioavailability, pharmacokinetics, and clinical efficacy, frankincense preparations are available as nutraceuticals but have not yet approved as a drug on the market. A major issue of commercially available frankincense nutraceuticals is the striking differences in their composition and quality, especially related to the content of boswellic acids (BAs) as active ingredients, mainly due to the use of material from divergent Boswellia species but also because of different work-up and extraction procedures. Here, we assessed three frequently used frankincense-based preparations for their BA content and the interference with prominent pro-inflammatory actions and targets that have been proposed, that is, 5-lipoxygenase and leukotriene formation in human neutrophils, microsomal prostaglandin E2 synthase-1, and inflammatory cytokine secretion in human blood monocytes. Our data reveal striking differences in the pharmacological efficiencies of these preparations in inflammation-related bioassays which obviously correlate with the amounts of BAs they contain. In summary, high-quality frankincense extracts display powerful anti-inflammatory effectiveness against multiple targets which can be traced back to BAs as bioactive ingredients.

A review of reusable insulin pens and features of TouStar-a new reusable pen with a dedicated cartridge.

BACKGROUND: Since the introduction of the first reusable insulin pen, the advancement in the design of these pens is still ongoing to develop a safe, more efficacious, less painful, and easy to use insulin pen device. MAIN BODY: Possible errors in insulin delivery can occur at any stage of insulin delivery such as during the prescription stage, dispensing stage, or at administration stage. Mismatch of the insulin pen and cartridge is not uncommon and is a potential risk for individuals with diabetes due to serious consequences associated with incorrect insulin usage. The similarities in insulin cartridges of different manufacturers with regard to color and product names could lead to mix-up of insulin pens and cartridges. These unmet needs have led to the ongoing search for developing insulin pens that can address these errors and provide more efficacious and safer choices for patients with diabetes. CONCLUSION: This review provides an overview of currently available reusable pens in the market and highlights the features of TouStar®, a new reusable pen with a dedicated cartridge intended to mitigate the risk of mismatch of the cartridge.

Absorption, pharmacokinetics, and safety of triclosan after dermal administration.

We evaluated the pharmacokinetics and safety of the antimicrobial agent triclosan after dermal application of a 2% triclosan-containing cream to six volunteers. Percutaneous absorption calculated from urinary excretion was 5.9% +/- 2.1% of the dose (mean +/- standard deviation). The amount absorbed suggests that daily application of a standard adult dose would result in a systemic exposure 890 times lower than the relevant no-observed-adverse-effect level. Triclosan can be considered safe for use in hydrophobic creams.

Extracting and Analyzing Pyrrolizidine Alkaloids in Medicinal Plants: A Review.

Pyrrolizidine alkaloids (PAs) are distributed in plant families of Asteraceae, Boraginaceae, and Fabaceae and serve in the chemical defense mechanism against herbivores. However, they became a matter of concern due to their toxicity associated with the high risk of intake within herbal preparations, e.g., phytopharmaceutical formulations, medicinal teas, or other plant-derived drug products. In 1992, the German Federal Ministry of Health established the first limits of PA content for fourteen medicinal plants. Because of the toxic effects of PAs, the Federal Institute of Risk Assessment (BfR) established more stringent limits in 2011, whereby a daily intake <0.007 µg/kg body weight was recommended and valid until 2018. A threefold higher limit was then advised by BfR. To address consumer safety, there is the need for more efficient extraction procedures along with robust, selective, and sensitive analytical methods to address these concerns. With the increased prevalence of, e.g., phytopharmaceutical formulations, this timely review comprehensively focuses on the most relevant extraction and analysis strategies for each of those fourteen plant genera. While a variety of extraction procedures has been reported, differences in PA content of up to 1110 ppm (0.11% (w/w)) were obtained dependent on the nature of the solvent and the applied extraction technique. It is evident that the efficient extraction of PAs requires further improvements or at least standardization of the extraction conditions. Comparing the various analytical techniques applied regarding selectivity and sensitivity, LC-MS methods appear most suited. This review shows that both standardized extraction and sensitive determination of PAs is required for achieving appropriate safety levels concerning public health in future.

Micellar solubilization enhances the anti-inflammatory effect of xanthohumol.

BACKGROUND: Xanthohumol is known to exert anti-inflammatory properties but has poor oral bioavailability. Using advanced micellization technology, it has been possible to markedly enhance its bioavailability. PURPOSE: In the present study, we compared the chronic anti-inflammatory activities of native and micellar xanthohumol in the rat adjuvant arthritis model, using diclofenac as a reference drug. METHODS: Adjuvant arthritis was induced by injecting Freund's complete adjuvant into the right hind paw of rats and monitoring paw volume over 3 weeks. The drugs were given daily for 3 weeks, starting from the day of adjuvant inoculation. Serum was collected at the end of the experiment to measure inflammatory and oxidative stress parameters. Statistical comparisons between different groups were carried out by one-way analysis of variance followed by Tukey-Kramer multiple comparison test. RESULTS: Micellar solubilized xanthohumol showed a better anti-inflammatory activity than its native form. The reduction in paw volume was reflected in corresponding changes in relevant mediators of inflammation like tumor necrosis factor-α, interleukin-6 and C-reactive protein, myloperoxidase and lipid peroxidation markers. CONCLUSION: The findings confirm that micellar solubilization of xanthohumol enhances its anti-inflammatory activity, probably as a result of improving its bioavailabilty. The solubilized xanthohumol may prove to be a promising adjuvant tool for anti-inflammatory treatment and a potential anti-inflammatory alternative to synthetic drugs.

Nonsteroidal anti-inflammatory drugs: a critical review on current concepts applied to reduce gastrointestinal toxicity.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used drugs worldwide. Nevertheless, their intake is frequently associated with gastrointestinal side effects, representing still an important medical and socio-economic problem. In recent years efforts focused on the development of highly selective COX-2 inhibitors with an improved gastric tolerability profile. However, severe cardiovascular adverse reactions challenged the initial enthusiasm in this new class of anti-inflammatory drugs. In addition, the market withdrawals of some coxibs led to a relative reluctance in prescribing COX-2 inhibitors in clinical practice. As a consequence, the interest for alternative approaches to reduce gastrointestinal side effects associated with NSAIDs has re-emerged. There are two main components of gastric damaging properties of NSAIDs: (1) the acute toxicity associated with the short-term intake of NSAIDs, which is principally caused by local irritation of the gastric mucosa (2) the chronic toxicity resulting mainly from systemic effects associated with prolonged administration of NSAIDs. Based on that background two different approaches were pursued in the search for GI sparing NSAIDs: a) modification of classical NSAIDs by associating them with phospholipids, cyclodextrins, or chemical moieties that release gastroprotective mediators and b) defining novel targets as well as developing new compounds like dual COX/5-LO or mPGES-1 inhibitors. This review provides the first comprehensive overview of all currently applied approaches taken to improve the risk-benefit ratio of NSAIDs focusing on the structure activity relationships and the respective mechanism of action underlying the individual approaches. The insight gained in this review is useful for further research activity in this field.