Xiaoying Zhuang

A Novel Nanoparticle Drug Delivery System: The Anti-inflammatory Activity of Curcumin Is Enhanced When Encapsulated in Exosomes

Monocyte-derived myeloid cells play vital roles in inflammation-related autoimmune/inflammatory diseases and cancers. Here, we report that exosomes can deliver anti-inflammatory agents, such as curcumin, to activated myeloid cells in vivo. This technology provides a means for anti-inflammatory drugs, such as curcumin, to target the inflammatory cells as well as to overcome unwanted off-target effects that limit their utility. Using exosomes as a delivery vehicle, we provide evidence that curcumin delivered by exosomes is more stable and more highly concentrated in the blood. We show that the target specificity is determined by exosomes, and the improvement of curcumin activity is achieved by directing curcumin to inflammatory cells associated with therapeutic, but not toxic, effects. Furthermore, we validate the therapeutic relevance of this technique in a lipopolysaccharide (LPS)-induced septic shock mouse model. We further show that exosomes, but not lipid alone, are required for the enhanced anti-inflammatory activity of curcumin. The specificity of using exosomes as a drug carrier creates opportunities for treatments of many inflammation-related diseases without significant side effects due to innocent bystander or off-target effects.

Treatment of Brain Inflammatory Diseases by Delivering Exosome Encapsulated Anti-inflammatory Drugs From the Nasal Region to the Brain

In this study, exosomes used to encapsulate curcumin (Exo-cur) or a signal transducer and activator of transcription 3 (Stat3) inhibitor, i.e., JSI124 (Exo-JSI124) were delivered noninvasively to microglia cells via an intranasal route. The results generated from three inflammation-mediated disease models, i.e., a lipopolysaccharide (LPS)-induced brain inflammation model, experimental autoimmune encephalitis and a GL26 brain tumor model, showed that mice treated intranasally with Exo-cur or Exo-JSI124 are protected from LPS-induced brain inflammation, the progression of myelin oligodendrocyte glycoprotein (MOG) peptide induced experimental autoimmune encephalomyelitis (EAE), and had significantly delayed brain tumor growth in the GL26 tumor model. Intranasal administration of Exo-cur or Exo-JSI124 led to rapid delivery of exosome encapsulated drug to the brain that was selectively taken up by microglial cells, and subsequently induced apoptosis of microglial cells. Our results demonstrate that this strategy may provide a noninvasive and novel therapeutic approach for treating brain inflammatory-related diseases.

Contribution of MyD88 to the Tumor Exosome-Mediated Induction of Myeloid Derived Suppressor Cells

In this study we observed that mice pretreated with tumor exosomes had a significant acceleration of tumor metastasis in the lung. Tumor metastasis correlated significantly with an increase in recruitment of more Myeloid-derived suppressor cells (MDSCs) in the lung of C57BL/6j (B6) mice pretreated with tumor exosomes. These effects were blunted when MyD88 knockout (KO) mice were pretreated with tumor exosomes. MDSCs induced by tumor exosomes and isolated from wild-type B6 mice also more potently inhibited T cell activation and induction of interleukin-6 and tumor necrosis factor-alpha than MDSCs isolated from the lung of MyD88 KO mice. In vitro, addition of tumor exosomes to bone marrow-derived CD11b(+)Gr-1(+) cells isolated from wild-type B6 mice resulted in more cytokine production, including tumor necrosis factor-alpha, interleukin-6, and the chemokine CCL2, than CD11b(+)Gr-1(+) cells isolated from MyD88 KO mice. Moreover, lower levels of CCL2 were observed in the lungs in MyD88 KO mice pretreated with tumor exosomes than that in wild-type mice. Together these data demonstrate a pivotal role for MyD88 in tumor exosome-mediated expansion of MDSCs and tumor metastasis.

Adipose Tissue Exosome-Like Vesicles Mediate Activation of Macrophage-Induced Insulin Resistance

OBJECTIVE We sought to determine whether exosome-like vesicles (ELVs) released from adipose tissue play a role in activation of macrophages and subsequent development of insulin resistance in a mouse model. RESEARCH DESIGN AND METHODS ELVs released from adipose tissue were purified by sucrose gradient centrifugation and labeled with green fluorescent dye and then intravenously injected into B6 ob/ob mice (obese model) or B6 mice fed a high-fat diet. The effects of injected ELVs on the activation of macrophages were determined through analysis of activation markers by fluorescence-activated cell sorter and induction of inflammatory cytokines using an ELISA. Glucose tolerance and insulin tolerance were also evaluated. Similarly, B6 mice with different gene knockouts including TLR2, TLR4, MyD88, and Toll-interleukin-1 receptor (TIR) domain–containing adaptor protein inducing interferon-β (TRIF) were also used for testing their responses to the injected ELVs. RESULTS ELVs are taken up by peripheral blood monocytes, which then differentiate into activated macrophages with increased secretion of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Injection of obELVs into wild-type C57BL/6 mice results in the development of insulin resistance. When the obELVs were intravenously injected into TLR4 knockout B6 mice, the levels of glucose intolerance and insulin resistance were much lower. RBP4 is enriched in the obELVs. Bone marrow–derived macrophages preincubated with recombinant RBP4 led to attenuation of obELV-mediated induction of IL-6 and TNF-α. CONCLUSIONS ELVs released by adipose tissue can act as a mode of communication between adipose tissues and macrophages. The obELV-mediated induction of TNF-α and IL-6 in macrophages and insulin resistance requires the TLR4/TRIF pathway.

Grape Exosome-like Nanoparticles Induce Intestinal Stem Cells and Protect Mice From DSS-Induced Colitis

Food-derived exosome-like nanoparticles pass through the intestinal tract throughout our lives, but little is known about their impact or function. Here, as a proof of concept, we show that the cells targeted by grape exosome-like nanoparticles (GELNs) are intestinal stem cells whose responses underlie the GELN-mediated intestinal tissue remodeling and protection against dextran sulfate sodium (DSS)-induced colitis. This finding is further supported by the fact that coculturing of crypt or sorted Lgr5⁺ stem cells with GELNs markedly improved organoid formation. GELN lipids play a role in induction of Lgr5⁺ stem cells, and the liposome-like nanoparticles (LLNs) assembled with lipids from GELNs are required for in vivo targeting of intestinal stem cells. Blocking β-catenin-mediated signaling pathways of GELN recipient cells attenuates the production of Lgr5⁺ stem cells. Thus, GELNs not only modulate intestinal tissue renewal processes, but can participate in the remodeling of it in response to pathological triggers.

Exosomes are endogenous nanoparticles that can deliver biological information between cells

Exosomal particular size of 30-100 nm matches the size criterion for nanoparticles, and opens up the possibility of using exosomes as a nanoparticle drug carrier. More importantly, exosomes released from different types of host cells have different biological effects and targeting specificities. Therefore, depending on the therapeutic goal, different types of exosomes can be combined with specific drugs and serve as carriers so that personalized medicine needs are met. In addition, exosomes do not appear to have cytotoxicity. Based on the perceived advantages of exosomes, they may well serve as a next generation drug delivery mechanism that combines nanoparticle size with a non-cytotoxic effect, target specificity, and a high drug carrying capacity, to make them useful in the treatment of a variety of diseases. This review will focus on exosomes as a biological nanoparticle drug carrier with emphasis on their immune-regulatory activities.

Interspecies communication between plant and mouse gut host cells through edible plant derived exosome-like nanoparticles

SCOPE Exosomes, small vesicles participating in intercellular communication, have been extensively studied recently; however, the role of edible plant derived exosomes in interspecies communication has not been investigated. Here, we investigate the biological effects of edible plant derived exosome-like nanoparticles (EPDENs) on mammalian cells. METHODS AND RESULTS In this study, exosome-like nanoparticles from four edible plants were isolated and characterized. We show that these EPDENs contain proteins, lipids, and microRNA. EPDENs are taken up by intestinal macrophages and stem cells. The results generated from EPDEN-transfected macrophages indicate that ginger EPDENs preferentially induce the expression of the antioxidation gene, heme oxygenase-1 and the anti-inflammatory cytokine, IL-10; whereas grapefruit, ginger, and carrot EPDENs promote activation of nuclear factor like (erythroid-derived 2). Furthermore, analysis of the intestines of canonical Wnt-reporter mice, i.e. B6.Cg-Tg(BAT-lacZ)3Picc/J mice, revealed that the numbers of β-galactosidase(+) (β-Gal) intestinal crypts are increased, suggesting that EPDEN treatment of mice leads to Wnt-mediated activation of the TCF4 transcription machinery in the crypts. CONCLUSION The data suggest a role for EPDEN-mediated interspecies communication by inducing expression of genes for anti-inflammation cytokines, antioxidation, and activation of Wnt signaling, which are crucial for maintaining intestinal homeostasis.

Delivery of therapeutic agents by nanoparticles made of grapefruit-derived lipids

Although the use of nanotechnology for the delivery of a wide range of medical treatments has potential to reduce adverse effects associated with drug therapy, tissue-specific delivery remains challenging. Here we show that nanoparticles made of grapefruit-derived lipids, which we call grapefruit-derived nanovectors (GNVs), can transport chemotherapeutic agents, siRNA, DNA expression vectors and proteins to different types of cells. We demonstrate the in vivo targeting specificity of GNVs by co-delivering therapeutic agents with folic acid, which in turn leads to significantly increasing targeting efficiency to cells expressing folate receptors. The therapeutic potential of GNVs was further demonstrated by enhancing the chemotherapeutic inhibition of tumor growth in two tumor animal models. GNVs are less toxic than nanoparticles made of synthetic lipids and, when injected intravenously into pregnant mice, do not pass the placental barrier, suggesting they may be a useful tool for drug delivery.

Grhl2 Determines the Epithelial Phenotype of Breast Cancers and Promotes Tumor Progression

Until now the essential transcription factor that determines the epithelial phenotype of breast cancer has not been identified and its role in epithelial-to-mesenchymal transition (EMT) and tumor progression remain unclear. Here, by analyzing large expression profiles of human breast cancer cells, we found an extraordinary correlation between the expression of Grainyhead transcription factor Grhl2 and epithelial marker E-cadherin. Knockdown of Grhl2 expression by shRNA in human mammary epithelial cell MCF10A leads to down-regulation of E-cadherin and EMT. Grhl2 is down-regulated in disseminated cancer cells that have undergone EMT, and over-expression of Grhl2 is sufficient to induce epithelial gene expression. Large clinical datasets reveal that expression of Grhl2 is significantly associated with poor relapse free survival and increased risk of metastasis in breast cancer patients. In mouse models, over-expression of Grhl2 significantly promotes tumor growth and metastasis. Further testing of several Grhl2 regulated genes leads to the same conclusions that the tumorigenic and metastatic potentials of tumor cells are linked to epithelial phenotype but not mesenchymal phenotype. In conclusion, our findings indicate that Grhl2 plays an essential role in the determination of epithelial phenotype of breast cancers, EMT and tumor progression.

Targeted Drug Delivery to Intestinal Macrophages by Bioactive Nanovesicles Released from Grapefruit

The gut mucosal immune system is considered to play an important role in counteracting potential adverse effects of food-derived antigens including nanovesicles. Whether nanovesicles naturally released from edible fruit work in a coordinated manner with gut immune cells to maintain the gut in a noninflammatory status is not known. Here, as proof of concept, we demonstrate that grapefruit-derived nanovesicles (GDNs) are selectively taken up by intestinal macrophages and ameliorate dextran sulfate sodium (DSS)-induced mouse colitis. These effects were mediated by upregulating the expression of heme oxygenase-1 (HO-1) and inhibiting the production of IL-1β and TNF-α in intestinal macrophages. The inherent biocompatibility and biodegradability, stability at wide ranges of pH values, and targeting of intestinal macrophages led us to further develop a novel GDN-based oral delivery system. Incorporating methotrexate (MTX), an anti-inflammatory drug, into GDNs and delivering the MTX-GDNs to mice significantly lowered the MTX toxicity when compared with free MTX, and remarkably increased its therapeutic effects in DSS-induced mouse colitis. These findings demonstrate that GDNs can serve as immune modulators in the intestine, maintain intestinal macrophage homeostasis, and can be developed for oral delivery of small molecule drugs to attenuate inflammatory responses in human disease.