Co-Delivery of Paclitaxel by a Capsaicin Prodrug Micelle Facilitating for Combination Therapy on Breast Cancer.

Poor anticancer ability, serious adverse reaction, and drug resistance against paclitaxel (PTX) have limited its clinical applications. When a mouse breast carcinoma cell line (4T1) was treated with both PTX and capsaicin (CAP), there was a synergistic anti-proliferative effect demonstrated with a combination index of 0.28. Therefore, a novel polyethylene glycol-derivatized CAP (PEG-Fmoc-CAP2) polymeric prodrug micellar carrier was developed and further encapsulated with PTX for antitumor combination treatment. The PEG-Fmoc-CAP2 polymeric micelles co-delivered with PTX achieved a 62.3% fraction of apoptotic cells in comparison to 45.4% fraction of apoptotic cells to that upon treatment with PTX alone. Comparable CAP amounts were found in the cell lysate treatment with PEG-Fmoc-CAP2-conjugated micelles to that of free CAP-treated 4T1 cells after 12 h treatment. Pharmacokinetic and biodistribution studies showed that the micelles possessed much longer circulation time in blood and preferential tumor tissue accumulation compared to the Taxol solution. Importantly, PTX/CAP-loaded micelles exhibited superior in vivo antitumor activity on the inhibition rate of tumor growth than other treatments (70.5% tumor growth reduction in PTX/CAP micelle-treated mice vs 57.8, 43.3, and 23.8% of tumor growth inhibition rate in PTX/PEG-Fmoc-OA2 micelles, Taxol, and PEG-Fmoc-CAP2 micelle-treated mice, respectively). Thus, the dual-functional PEG-Fmoc-CAP2 polymeric prodrug micelles are a promising co-delivery nanosystem for achieving synergistic antitumor efficacy of PTX and CAP.

Molecular vaccine prepared by fusion of XCL1 to the multi-epitope protein of foot-and-mouth disease virus enhances the specific humoural immune response in cattle.

Targeting antigen to dendritic cells (DCs) is a promising way to manipulate the immune response and to design prophylactic molecular vaccines. In this study, the cattle XCL1, ligand of XCR1, was fused to the type O foot-and-mouth disease virus (FMDV) multi-epitope protein (XCL-OB7) to create a molecular vaccine antigen, and an △XCL-OB7 protein with a mutation in XCL1 was used as the control. XCL-OB7 protein specifically bound to the XCR1 receptor, as detected by flow cytometry. Cattle vaccinated with XCL-OB7 showed a significantly higher antibody response than that to the △XCL-OB7 control (P < 0.05). In contrast, when XCL-OB7 was incorporated with poly (I:C) to prepare the vaccine, the antibody response of the immunized cattle was significantly decreased in this group and was lower than that in the △XCL-OB7 plus poly (I:C) group. The FMDV challenge indicated that cattle immunized with the XCL-OB7 alone or the △XCL-OB7 plus poly (I:C) obtained an 80% (4/5) clinical protective rate. However, cattle vaccinated with △XCL-OB7 plus poly (I:C) showed more effective inhibition of virus replication than that in the XCL-OB7 group after viral challenge, according to the presence of antibodies against FMDV non-structural protein 3B. This is the first test of DC-targeted vaccines in veterinary medicine to use XCL1 fused to FMDV antigens. This primary result showed that an XCL1-based molecular vaccine enhanced the antibody response in cattle. This knowledge should be valuable for the development of antibody-dependent vaccines for some infectious diseases in cattle.

Efficacy of Polyethylene Glycol Electrolyte Powder Combined With Linaclotide for Colon Cleansing in Patients With Chronic Constipation Undergoing Colonoscopy: A Multicenter, Single-Blinded, Randomized Controlled Trial.

INTRODUCTION: Constipation is an independent risk factor for poor bowel preparation. This study aimed to evaluate the bowel cleansing efficacy and safety of polyethylene glycol (PEG) combined with linaclotide (lin) for colonoscopy in patients with chronic constipation (CC). METHODS: This single-blinded, randomized, controlled, and multicenter study was conducted from July 2021 to December 2022 at 7 hospitals. Patients with CC who underwent colonoscopies were enrolled and randomly assigned to 4 groups with split-PEG regimens: 4L-PEG group, 4L-PEG+1d-Lin group, 3L-PEG+1d-Lin group, and 3L-PEG+3d-Lin group. The primary outcome was rates of adequate bowel preparation, defined as a total BBPS score ≥6 and a score ≥2 for each segment. Secondary outcomes were adverse effects, sleep quality, willingness to repeat the colonoscopy, adenoma detection rate, and polyp detection rate. RESULTS: Five hundred two patients were enrolled. The rates of adequate bowel preparation (80.0% vs 60.3%, P < 0.001; 84.4% vs 60.3%, P < 0.001) and the total Boston Bowel Preparation Scale (BBPS) scores (6.90 ± 1.28 vs 6.00 ± 1.61, P < 0.001; 7.03 ± 1.24 vs 6.00 ± 1.61, P < 0.01) in the 4L-PEG+1d-Lin group and the 3L-PEG+3d-Lin group were superior to that in the 4L-PEG group. Compared with the 4L-PEG group, the 4L-PEG+1d-Lin group (66.7% vs 81.7%, P = 0.008) and the 3L-PEG+3d-Lin group (75.0% vs 81.7%, P = 0.224) had a lower percentage of mild adverse events. No statistically significant difference in willingness to repeat the colonoscopy, sleep quality, polyp detection rate, or adenoma detection rate was observed among groups. DISCUSSION: PEG combined with linaclotide might be an effective method for bowel preparation before colonoscopy in patients with CC.

Glycyrrhetinic acid-conjugated polymeric prodrug micelles co-delivered with doxorubicin as combination therapy treatment for liver cancer.

Significant synergy of doxorubicin (DOX) and glycyrrhizic acid (GA) in inhibiting the proliferation of cancer cells was demonstrated in the human hepatocellular carcinoma cell line, HepG2. A novel polymeric prodrug micellar carrier based on polyethylene glycol-derivatized GA (PEG-Fmoc-GA), was developed for co-delivery of DOX as a combined anti-cancer treatment. The PEG-Fmoc-GA polymeric prodrug micelles achieved a more effective synergistic action on cell proliferation inhibition and apoptosis induction, when co-delivered with DOX, which can be attributed to the dual effect of the cleaved GA and loaded DOX. PEG-Fmoc-GA conjugated micelles significantly facilitated the intracellular uptake of DOX by HepG2 cells, when compared to a DOX solution alone. In addition, DOX encapsulated in PEG-Fmoc-GA micelles displayed longer blood circulation time, larger drug concentration area under the curve, decreased volume distribution and clearance than DOX solution. Biodistribution studies showed that DOX/PEG-Fmoc-GA micelles were preferentially accumulated at the tumor site. Importantly, DOX/PEG-Fmoc-GA micelles demonstrated a more pronounced therapeutic efficacy in vivo compared with DOX alone with respect to both tumor growth inhibition and overall survival in a HepG2 xenograft model. Thus, PEG-Fmoc-GA polymeric prodrug micelles represent a promising dual-function co-delivery system to achieve anti-cancer synergistic activity of DOX and GA.

Enhanced encapsulation and bioavailability of breviscapine in PLGA microparticles by nanocrystal and water-soluble polymer template techniques.

Poly (lactide-co-glycolide) (PLGA) microparticles are widely used for controlled drug delivery. Emulsion methods have been commonly used for preparation of PLGA microparticles, but they usually result in low loading capacity, especially for drugs with poor solubility in organic solvents. In the present study, the nanocrystal technology and a water-soluble polymer template method were used to fabricate nanocrystal-loaded microparticles with improved drug loading and encapsulation efficiency for prolonged delivery of breviscapine. Breviscapine nanocrystals were prepared using a precipitation-ultrasonication method and further loaded into PLGA microparticles by casting in a mold from a water-soluble polymer. The obtained disc-like particles were then characterized and compared with the spherical particles prepared by an emulsion-solvent evaporation method. X-ray powder diffraction (XRPD) and confocal laser scanning microscopy (CLSM) analysis confirmed a highly-dispersed state of breviscapine inside the microparticles. The drug form, loading percentage and fabrication techniques significantly affected the loading capacity and efficiency of breviscapine in PLGA microparticles, and their release performance as well. Drug loading was increased from 2.4% up to 15.3% when both nanocrystal and template methods were applied, and encapsulation efficiency increased from 48.5% to 91.9%. But loading efficiency was reduced as the drug loading was increased. All microparticles showed an initial burst release, and then a slow release period of 28days followed by an erosion-accelerated release phase, which provides a sustained delivery of breviscapine over a month. A relatively stable serum drug level for more than 30days was observed after intramuscular injection of microparticles in rats. Therefore, PLGA microparticles loaded with nanocrystals of poorly soluble drugs provided a promising approach for long-term therapeutic products characterized with preferable in vitro and in vivo performance.

Preparation of a magnetofluorescent nano-thermometer and its targeted temperature sensing applications in living cells.

A magnetic fluorescent nano-thermometer is presented. To fabricate the nano-thermometer, magnetic nanoparticles (Fe3O4) were first encapsulated with a silica layer. Then a poly (N-isopropylacrylamide) (pNIPAM) copolymer shell with Rhodamine B isothiocyanate (RhBITC) embedded inside was further coated, which was denoted as the pNIPAM-co-RhBITC shell. Finally, gold nanoparticles were introduced onto the copolymer shell by in-situ growth method and the nano-thermometer (denoted as Fe3O4@SiO2@(pNIPAM-co-RhBITC)/Au) was obtained. The nano-thermometer shows dual responses to both magnetism and temperature. Specifically, the fluorescence intensity of the nano-thermometer decreases as the temperature increases, which makes the nano-thermometer suitable for intracellular temperature sensing. Using this nano-thermometer, temperature changes in live HeLa cells can be successfully detected. Moreover, due to the Fe3O4 component, magnetic field guided targeting can be realized, thus targeted temperature sensing can be achieved for living cells. Cellular temperature changes can be easily detected using the proposed nano-thermometer in the range of 26°C to 41°C with a sensitivity of -4.84%°C(-1).

Ag@4ATP-coated liposomes: SERS traceable delivery vehicles for living cells.

A liposome-Ag nanohybrid has been demonstrated as a SERS traceable intracellular drug nanocarrier. Liposomes have been introduced for their special qualities in drug delivery systems. In essence, 4-aminothiophenol (4ATP) tagged Ag nanoparticles (Ag@4ATP) were adsorbed onto the surfaces of liposomes via electrostatic interactions, in which 4ATP was used as a SERS reporter. In such a nanohybrid, the locations of the carrier can be tracked by SERS signals while those of the drugs can be monitored through their fluorescence, allowing the simultaneous investigation of the intracellular distribution of both the carriers and the drugs. Our experimental results suggest that the reported liposomal system has substantial potential for intracellular drug delivery.