Amplification of anticancer efficacy by co-delivery of doxorubicin and lonidamine with extracellular vesicles.

Chemotherapy is commonly used for the treatment of lung cancer, but strong side effects and low treatment efficacy limit its clinical application. Here, extracellular vesicles (EVs) as natural drug delivery carriers were used to load conventional anticancer drug doxorubicin (DOX) and a chemosensitizer lonidamine (LND). Two types of EVs with different sizes (16k EVs and 120k EVs) were prepared using different centrifugation forces. We found that co-delivery of DOX and LND with both EVs enhanced the cytotoxicity and reduced the dose of the anticancer drug significantly in vitro. Effective delivery of anti-cancer drugs to cancer cells was achieved by direct fusion of EVs with the plasma membrane of cancer cells. On the other hand, DOX and LND inhibited cancer cell proliferation by increasing DNA damage, suppressing ATP production, and accelerating ROS generation synergistically. DOX and LND loaded EVs were also applied to the mouse lung cancer model and exhibited significant anticancer activity. In vivo study showed that smaller EVs exhibited higher anticancer efficiency. In conclusion, the co-delivery of the anticancer drug and the chemosensitizer with EVs may have potential clinical applications for cancer therapy.

6-Gingerol protects cardiocytes H9c2 against hypoxia-induced injury by suppressing BNIP3 expression.

Background: Cardiomyocytes loss is the predominant pathogenic characteristic in the hypoxia-induced injury. Meanwhile, it has been corroborated that Bcl-2 E1B 19-KDa interacting protein 3 (BNIP3) provokes apoptosis and autophagy. For moderating cardiomyocytes loss, we initially probed the cyto-protection effects of 6-Gingerol (6 G), meanwhile, its potential mechanisms associated with BNIP3 were elucidated in our studies. Methods: We pretreated cardiomyocytes H9c2 cells with 6 G at different concentrations (0-100 µM) before exposure to hypoxia. Thereafter, the cell viability, lactate dehydrogenase (LDH), apoptosis and protein expression were respectively assessed using cell counting kit-8 and methyl thiazolyl tetrazolium (MTT) assay, LDH assay kit, Annexin V-fluorescein isothiocyannate/propidium iodide (Annexin V-FITC/PI) apoptosis detection kit and Western blotting analysis. In addition, we also analyzed BNIP3 level after treatment. Moreover, we enforced the exogenous overexpression of BNIP3 and then evaluated the cell viability, apoptosis, and protein level again. Results: In our present work, we observed that the cell viability was promoted by 6 G in the hypoxia-induced H9c2 cells in a dose-dependent manner. Moreover, hypoxia-induced LDH release, apoptosis and autophagy were inhibited by 6 G pretreatment through promoting phosphorylation of PI3K, AKT and mTOR. Remarkably, accumulation of BNIP3 protein was significantly reduced by 6 G in hypoxia-induced H9c2 cells. Mechanistically, 6 G initiated the phosphorylated expression of PI3K, AKT and mTOR by down-regulating BNIP3 with reducing cardiomyocytes apoptosis and autophagy. Conclusion: Hypoxia-induced cardiomyocytes injury was ameliorated by 6 G through suppressing BNIP3 expression with triggering PI3K/AKT/mTOR signalling pathway.

Astragalus polysaccharide alleviates LPS-induced inflammation injury by regulating miR-127 in H9c2 cardiomyoblasts.

Astragalus polysaccharide (APS) has been widely reported to play an important role in inflammatory response. In this study, we aimed to explore the effects and underlying mechanisms of APS on lipopolysaccharide (LPS)-induced inflammation injury in H9c2 cardiomyoblasts. H9c2 cells were treated with different concentrations of APS, and cell viability was detected by the Cell Counting Kit-8 (CCK-8) assay. Then, the effect of APS on cell viability and apoptosis induced by LPS was determined by CCK-8, flow cytometry, and western blot. The expression and release of inflammatory cytokines were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and enzyme-linked immunosorbent assay (ELISA). Furthermore, expression of miR-127 in H9c2 cells was analyzed by qRT-PCR, and knocked down by transfection with miR-127 inhibitor. Western blot was used to analyze signaling pathway molecules. APS had no effect on H9c2 cells viability. However, APS could alleviate LPS-induced inflammation injury by increasing cell viability, reducing apoptosis, and inhibiting release of inflammatory cytokines in H9c2 cells ( P < 0.05). Additionally, we found that APS increased toll-like receptor 4 (TLR4) expressions in LPS-treated H9c2 cells. Mechanistically, we found that APS exerted the protective effect by down-regulating LPS-increased expression of miR-127 ( P < 0.05), inhibiting nuclear factor kappa B (NF-κB), JNK and promoting phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signaling pathways in LPS-treated H9c2 cells. The results demonstrated that APS could protect H9c2 cells against LPS-induced inflammation injury, which might be partially due to miR-127 down-regulation and regulation of NF-κB, JNK, and PI3K/AKT signaling pathways. These findings indicated that APS might be a potential therapeutic drug for treatment of myocarditis.

A novel selective VPAC2 agonist peptide-conjugated chitosan modified selenium nanoparticles with enhanced anti-type 2 diabetes synergy effects.

A novel neuroendocrine peptide, pituitary adenylate cyclase activating peptide (PACAP), was found to have an important role in carbohydrate or lipid metabolism and was susceptible to dipeptidyl peptidase IV degradation. It can not only mediate glucose-dependent insulin secretion and lower blood glucose by activating VPAC2 receptor, but also raise blood glucose by promoting glucagon production by VPAC1 receptor activation. Therefore, its therapeutic application is restricted by the exceedingly short-acting half-life and the stimulatory function for glycogenolysis. Herein, we generated novel peptide-conjugated selenium nanoparticles (SeNPs; named as SCD), comprising a 32-amino acid PACAP-derived peptide DBAYL that selectively binds to VPAC2, and chitosan-modified SeNPs (SeNPs-CTS, SC) as slow-release carrier. The circulating half-life of SCD is 14.12 h in mice, which is 168.4-and 7.1-fold longer than wild PACAP (~5 min) and DBAYL (~1.98 h), respectively. SCD (10 nmol/L) significantly promotes INS-1 cell proliferation, glucose uptake, insulin secretion, insulin receptor expression and also obviously reduces intracellular reactive oxygen species levels in H2O2-injured INS-1 cells. Furthermore, the biological effects of SCD are stronger than Exendin-4 (a clinically approved drug through its insulinotropic effect), DBAYL, SeNPs or SC. A single injection of SCD (20 nmol/kg) into db/db mice with type 2 diabetes leads to enhanced insulin secretion and sustained hypoglycemic effect, and the effectiveness and duration of SCD in enhancing insulin secretion and reducing blood glucose levels are much stronger than Exendin-4, SeNPs or SC. In db/db mice, chronic administration of SCD by daily injection for 12 weeks markedly improved glucose and lipid profiles, insulin sensitivity and the structures of pancreatic and adipose tissue. The results indicate that SC can play a role as a carrier for the slow release of bioactive peptides and SCD could be a hopeful therapeutic against type 2 diabetes through the synergy effects of DBAYL and SeNPs.

A novel recombinant slow-release TNF α-derived peptide effectively inhibits tumor growth and angiogensis.

RMP16, a recombinant TNF α-derived polypeptide comprising a specific human serum albumin (HSA)-binding 7-mer peptide identified by phage display screening (WQRPSSW), a cleavage peptide for Factor Xa (IEGR), and a 20-amino acid bioactive peptide P16 (TNF α segment including amino acid residues 75-94), was prepared by gene-engineering technology. RMP16 showed prolonged half-life, 13.11 hours in mice (half-lives of P16 and TNF α are 5.77 and 29.0 minutes, respectively), and obviously higher receptor selectivity for TNFRI than TNF α. RMP16 had significant inhibition effects for multiple tumor cells, especially prostate cancer Du145 cells, and human vascular endothelial cells but not for human mammary non-tumorigenic epithelial cells. RMP16 can more effectively induce apoptosis and inhibit proliferation for DU145 cells than P16 and TNF α via the caspase-dependent apoptosis pathway and G0/G1 cell cycle arrest. In nude mice with transplanted tumor of DU145 cells, RMP16 significantly induced apoptosis and necrosis of tumor tissues but causing less side effects, and tumor inhibitory rate reached nearly 80%, furthermore, RMP16 can potently inhibit tumor angiogenesis and neovascularization. These findings suggest that RMP16 may represent a promising long-lasting antitumor therapeutic peptide with less TNF α-induced toxicity.

A New Recombinant PACAP-Derived Peptide Efficiently Promotes Corneal Wound Repairing and Lacrimal Secretion.

PURPOSE: A new recombinant pituitary adenylate cyclase-activating polypeptide (PACAP)-derived peptide, MPAPO, which has higher stability and PAC1-specific potency, was generated. The actions of MPAPO on corneal wound repairing and lacrimal secretion were examined. METHODS: MPAPO was prepared and identified by gene recombination, high-performance liquid chromatography (HPLC), and electrospray ionization mass spectrometry (ESI-MS). Stability assay was performed by HPLC-ESI-MS. PAC1-specific binding and potency assays were performed using PAC1-CHO cells. C57BL/6 mice and Japanese white rabbits were respectively used to analyze the effects of MPAPO on corneal wound repairing and lacrimal fluid secretion. Tetrazolium-based colorimetric assay (MTT), immunofluorescence, gene microarrays, and Western blot assay were performed to measure the effects of MPAPO on corneal epithelial cell proliferation, synapse growth, and gene differential expression of trigeminal ganglion cells. RESULTS: As compared with the wild PACAP, the in vitro stability and PAC1-specific potency of MPAPO with four mutations (M17L, L27K and M, K, respectively, added to the N- and C-terminus) were increased approximately 31- and 2-fold, respectively. MPAPO can significantly promote the proliferation of mouse corneal epithelium cells and the synapse growth of trigeminal ganglion cells. In experimental animals, MPAPO performed a complete corneal epithelial wound closure in 30 hours and significantly inhibited corneal neovascularization, and the effects were obviously stronger than for wild PACAP and recombinant bovine (rb)-bFGF (an anti-corneal wound drug). Furthermore, MPAPO can increase the lacrimal secretion, which may efficiently improve dry eye. CONCLUSIONS: MPAPO may represent a promising external therapeutic peptide for corneal wound repairing or dry eye.

A recombinant slow-release PACAP-derived peptide alleviates diabetes by promoting both insulin secretion and actions.

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuroendocrine factor that activates both the receptor VPAC1 and VPAC2. Although PACAP possesses insulinotropic activity, its therapeutic application is limited by the extremely short acting half-life and the stimulatory effects on glucagon production via a VPAC1-dependent mechanism. Here we have generated a recombinant PACAP-derived peptide (named as MHDBAY) comprising a 7-mer albumin-binding peptide identified by phage display screening (WQRPSSW), a cleavage peptide for Factor Xa (FXa) and dipeptidyl peptidase IV (DPP IV), and a 31-amino acid PACAP-derived peptide (DBAY) that can specifically bind to the VPAC2 receptor. MHDBAY binds to albumin both in vitro and in animals, thereby leading to an orderly slow release of the active peptide DBAY via the protease cleavage. In db/db mice and New Zealand rabbits, the circulating half-life of MHDBAY is approximately 12.2 h, which is 146-fold longer than DBAY (∼5 min). A single injection of MHDBAY into db/db diabetic mice markedly increases insulin secretion, thereby leading to sustained alleviation of hyperglycemia. The potency and duration of MHDBAY in increasing insulin secretion and decreasing blood glucose levels is much greater than Exendin-4, an anti-diabetic drug via its insulinotropic actions. Furthermore, chronic administration of MHDBAY by daily injection for 8 weeks significantly improves both glucose and lipid profiles and also greatly increases insulin sensitivity in db/db mice. These findings suggest that serum albumin may act as a reservoir for slow-release of small bioactive peptides, and MHDBAY may represent a promising therapeutic peptide for diabetes.