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Herbal Products for the Treatment of Psoriasis
Published in Siba P. Raychaudhuri, Smriti K. Raychaudhuri, Debasis Bagchi, Psoriasis and Psoriatic Arthritis, 2017
Anna Herman, Andrzej P. Herman
Oral delivery is the most convenient, safe, and widely accepted route for the administration of drugs. Disadvantages include the possibility of irregular and unpredictable absorption, depending on the physiochemical properties of the drug and the anatomic and biochemical features of the gastrointestinal tract (Doshi 2007). In this route of administration, the therapeutic efficiency of herbal products depends on the liberation of active constituents, their stability, and their absorption in intestinal tract. During oral administration, the bioavailability of herbal compounds generally decreases (due to incomplete absorption and first-pass metabolism) or may vary from patient to patient. Furthermore, orally active compounds must achieve acceptable plasma levels before they can exert a clinical effect in vivo. Herbal product bioavailability and high exposure in plasma levels after oral administration spread to a therapeutic effect (Bhattaram et al. 2002). Curcumin from C. longa, often used in orally administrated product for psoriasis treatment, revealed low bioavailability due to its limited intestinal uptake and rapid metabolism (Anand et al. 2007; Yang et al. 2007). Micronized powder and liquid micellar formulation of curcumin (Schiborr et al. 2014), nanoparticle encapsulation of curcumin (Shaikh et al. 2009), curcumin-loaded solid lipid nanoparticles (Kakkar et al. 2011), and silica-coated flexible liposomes as a nanohybrid delivery system (C. Li et al. 2012) are described in literature examples for the enhancement of the oral bioavailability of curcumin. Also, glycyrrhizin (G. glabra) used in psoriasis treatment products has a poor oral bioavailability in both rats and humans (Isbrucker and Burdock 2006). It was found that slow conversion of glycyrrhizin into glycyrrhetic acid (major metabolite of glycyrrhizin) in the intestine, as well as poor intestinal absorption of glycyrrhetic acid, caused their low bioavailability (Takeda et al. 1996). The use of the formulation of glycyrrhizin as sodium deoxycholate–phospholipid mixed nanomicelles (Jin et al. 2012) could enhance glycyrrhizin absorption in the gastrointestinal tract and improve their bioavailability. Astilbin, flavonoid isolated from the rhizome of Smilax glabra (Rhizoma Smilacis Glabrae), is a promising immunosuppressant for immune-related diseases such as psoriasis, but is limited in clinical application due to its poor water solubility, difficult oral absorption, and low bioavailability (He et al. 2014). The self-microemulsifying drug delivery system (SMEDDS) (Mezghrani et al. 2011) and a combination of PVP K30 and Tween 80 (He et al. 2014) showed a significant enhancement of astilbin bioavailability. Unfortunately, in many cases, little is known about the bioavailability of herbal products and potentially new active compounds. A better understanding of the pharmacokinetics and bioavailability of phytopharmaceuticals becomes an important issue in linking data from pharmacological assays and clinical effects (Bhattaram et al. 2002).
Rapid oral transmucosal delivery of zaleplon–lavender oil utilizing self-nanoemulsifying lyophilized tablets technology: development, optimization and pharmacokinetic evaluation
Published in Drug Delivery, 2022
Sarah A. Ali, Nabil A. Alhakamy, Khaled M. Hosny, Eman Alfayez, Deena M. Bukhary, Awaji Y. Safhi, Moutaz Y. Badr, Rayan Y. Mushtaq, Majed Alharbi, Bader Huwaimel, Mohammed Alissa, Sameer Alshehri, Ali H. Alamri, Taha Alqahtani
The use of NEs in the pharmaceutical industry is especially promising; a number of patents have been submitted for NE formulations, but many of these NEs have not been marketed yet (Tiwari et al., 2006). Cui et al., for example, created a unique self-microemulsifying drug delivery system that successfully increased curcumin solubility and oral absorption (Zülli et al., 2006). Similarly, previous studies have reported that the o/w NEs containing the hydrophobic anticancer drug paclitaxel overcame the drug’s low oral bioavailability. They used peanut oil as the internal oil phase, egg lecithin as the principal emulsifier, and water as the exterior phase (Zidan et al., 2015). Ubiquinone, also known as Coenzyme Q10 (CoQ10), is a naturally occurring substance in the body; it is utilized for the production of energy within cells and acts as an antioxidant agent. CoQ10 is also available as a dietary aid. In this form it may have the major drawback of low oral bioavailability as a result of its high lipophilicity. A recent study revealed the significant enhancement of the bioavailability of CoQ10 following its encapsulation in NEs. There was even more improvement with NEs that contained tocopherol and CoQ10 in separate nanodroplets (Chen et al., 2015).
Enhancement of the anticancer effect of atorvastatin-loaded nanoemulsions by improving oral absorption via multivalent intestinal transporter-targeting lipids
Published in Drug Delivery, 2022
Laxman Subedi, Prashant Pandey, Bikram Khadka, Jung-Hyun Shim, Seung-Sik Cho, Seho Kweon, Youngro Byun, Ki-Taek Kim, Jin Woo Park
To obtain stable ATV-loaded NEs (ATV-NEs), 10 mg of ATV were dispersed in 42 mg of oil (Capryol 90). Subsequently, 550 mg of a mixture of surfactant and co-surfactant (Smix; Tween 80:Transcutol HP, 1:2 [w/w]), and 50 mg TPGS were added to form a self-microemulsifying drug delivery system (Ishak & Osman, 2015; Jha et al., 2020a). Furthermore, to examine the improvement in permeability of ATV via ASBT- and SMVT-mediated transport, DOTAP was integrated with DOCA at a molar ratio of 1:1 by ionic complexation to form DOCA-TAP, as described previously (Jha et al., 2020a). Then, effective enhancers, such as DOCA-TAP and/or Biotinyl PE, were anchored onto the Smix layer of ATV-NEs using a low-energy spontaneous emulsification method. Separately, DOTAP or DOCA was incorporated into the ATV-NEs to confirm the anchoring of DOCA-TAP onto the Smix (Figure 1(A), Table 1).
Ocular Self-Microemulsifying Drug Delivery System of Prednisolone Improves Therapeutic Effectiveness in the Treatment of Experimental Uveitis
Published in Ocular Immunology and Inflammation, 2019
Rahul Tiwari, Vibhuti Dubey, Karthikeyan Kesavan
Ocular therapy would be significantly improved if the precorneal residence time of drugs could be increased.3,4 several new preparations such as nanoparticles5 liposomes, 6 microspheres,7 nanosuspension,8 nanoemulsion,9 and microemulsion10 have been developed for ophthalmic use, not only to prolong the contact time of the vehicle on the ocular surface but also to slow down the drug elimination. Self-microemulsifying drug delivery system (SMEDDS) is isotropic mixtures of an oil, surfactant, co surfactant (or solubilizer), and drug, which has ability to form fine oil-in-water (o/w) microemulsions in the size range of less than 100 nm under gentle agitation following dilution by aqueous phases.11,12