Yeast Beta Glucan Delivery Systems:
Here's a new publication on yeast beta glucan drug delivery carriers that supports CZO's interests and explains why yeast beta glucan is a promising carrier.
Bioinspired yeast-based β-glucan system for oral drug delivery - ScienceDirect
Recently, naturally derived carriers have emerged, from which yeast-based β-glucan carriers have attracted significant attention. The yeast-based β-glucan carrier features an excellent safety profile, reproducibility, and superior physicochemical characteristics. Moreover, the yeast-based β-glucan carrier can overcome the current challenges due to the specific function of its main component (β-glucan), making it an ideal oral carrier for drug delivery.
First, yeast-based β-glucan carriers can avoid being digested in the harsh gastrointestinal environment because they lack the enzymes that degrade β-glucan and β-glucan possesses acid-resistant properties, which exhibits potential application value in oral drug delivery. And studies have demonstrated that the yeast-based β-glucan drug system was stable in simulated gastric fluid with slow release performance (Ren et al., 2018; Sun et al., 2020). Additionally, yeast-based β-glucan carriers can overcome the multiple barriers of the gastrointestinal tract and avoid liver first pass effect by specific transport routes. Studies have been reported that yeast particles can be taken up by M cells after 1 h, and most yeast particles were found in macrophages in Peyer's patches (PPs) after 4 h, which was confirmed by transmission electron microscopy imaging (De Smet et al., 2013). Beier et al. investigated yeast particles that can accumulate in the PPs of minipigs in 1998 (Beier & Gebert, 1998). Further studies revealed that yeast can reach the remote diseased region with phagocytes migrating into the lymphatic system after being phagocytosed by M cells and phagocytes (De Smet et al., 2014). As a yeast-derived carrier, the β-glucan carrier can mimic the behavior of yeast, which is first transferred to the PPs via M cells, endocytosed by macrophages within the PPs, and then transported to distant diseased sites through macrophages (Aouadi et al., 2009; Fang et al., 2021; Li, Peng, et al., 2019; Li, Zeng, et al., 2019; Miao et al., 2019). Baker's yeast (Saccharomyces cerevisiae) is the most widely used yeast strain for basic research, since it has been generally recognized as safe (Yao et al., 2022). Although intact yeast can carry different pharmaceutical ingredients for oral delivery, the narrow intracellular space of yeast and the low porosity of their cell wall affect the encapsulation of biological agents into yeast, which restricts their application (Dadkhodazade et al., 2021b; Ivanova, 2021; Sabu et al., 2019; Silva et al., 2021). Fortunately, the yeast-derived β-glucan carrier obtained by different methods to treat yeast exhibited extremely promising prospects for targeted delivery of drugs to desired sites after oral administration. In recent years, various strategies have been developed for the yeast-based β-glucan carriers to encapsulate drugs, including passive diffusion, vacuum infusion, slurry evaporation, polymeric hydrogel encapsulation, layer-by-layer packaging, and nano-in-micro methods (Ehlerding et al., 2018; Li, Zhao, et al., 2020a; Li, Zhao, et al., 2020b; Tan, Wang, & Sun, 2021a; Tan, Wang, & Sun, 2021b). Based on the above drug encapsulation strategies, yeast-based β-glucan carriers have been used to construct oral targeting delivery systems loaded with therapeutic agents for various diseases, including inflammatory bowel disease, osteoarthritis, atherosclerosis, organ transplantation, cancer, etc., as shown in Fig. 1. This review summarizes the development of yeast-based β-glucan systems for oral drug delivery.
Applications of yeast-based drug delivery systems
Based on the advantages of yeast-based β-glucan systems, including their non-digestibility in the gastrointestinal environment, good safety profile and cost-effectiveness, they have been widely applied to oral drug delivery. Notably, the key components of the system, β-1,3-D-glucans as PAMPs, can bind to pathogen recognition receptors of macrophages (such as Dectin-1, and complement receptor 3) (Chan et al., 2009; Herre et al., 2004; Huang et al., 2012), indicating that the yeast-based β-glucan
Conclusions and future perspectives
Yeast-based drug delivery systems have become an attractive area of research in recent years, due to their desirable performance in targeting accumulation in diseased regions, safety and efficiency, convenience and patient compliance. To overcome the low loading capacity of nave yeasts, yeasts were pretreated with chemical reagents, physical stimulation and enzymes. These pretreated yeasts as yeast-based carriers provide higher permeability and more space for drug loading. Based on their