Application of targeted liposomes-based salvianolic acid A for the treatment of ischemic stroke.

Novel therapeutics for the treatment of ischemic stroke remains to be the unmet clinical needs. Previous studies have indicated that salvianolic acid A (SAA) is a promising candidate for the treatment of the brain diseases. However, SAA has poor absolute bioavailability and does not efficiently cross the intact blood-brain barrier (BBB), which limit its efficacy. To this end we developed a brain-targeted liposomes for transporting SAA via the BBB by incorporating the liposomes to a transport receptor, insulin-like growth factor-1 receptor (IGF1R). The liposomes were prepared by ammonium sulfate gradients loading method. The prepared SAA-loaded liposomes (Lipo/SAA) were modified with IGF1R monoclonal antibody to generate IGF1R antibody-conjugated Lipo/SAA (IGF1R-targeted Lipo/SAA). The penetration of IGF1R-targeted Lipo/SAA into the brain was confirmed by labeling with Texas Red, and their efficacy were evaluate using middle cerebral artery occlusion (MCAO) model. The results showed that IGF1R-targeted Lipo/SAA are capable of transporting SAA across the BBB into the brain, accumulation in brain tissue, and sustained releasing SAA for several hours. Administration o IGF1R-targeted Lipo/SAA notably reduced infarct size and neuronal damage, improved neurological function and inhibited cerebral inflammation, which had much higher efficiency than no-targeted SAA.

A systemic analysis of monocarboxylate transporters in ovarian cancer and possible therapeutic interventions.

Monocarboxylate transporters (MCTs) play an immense role in metabolically active solid tumors by regulating concentration-dependent transport of different important monocarboxylates including pyruvate and lactate and are encoded by the SLC16A family of genes. Given the vast array of functions, these transporters play in oncogenesis, our objective was to look into the association of MCT1 (SLC16A1), MCT2 (SLC16A7), MCT3 (SLC16A8), and MCT4 (SLC16A3) with Epithelial ovarian cancer (EOC) pathophysiology by exploiting various publicly available databases and web resources. Few of the in silico findings were confirmed via in vitro experiments in EOC cell lines, SKOV3 and OAW-42. MCT1 and MCT4 were found to be upregulated at the mRNA level in OC tissues compared to normal. However, only higher level of MCT4 mRNA was found to be associated with poor patient survival. MCT4 was positively correlated with gene families responsible for invasion, migration, and immune modification, proving it to be one of the most important MCTs for therapeutic intervention. We compared the effects of MCT1/2 blocker SR13800 and a broad-spectrum MCT blocker α-Cyano Hydroxy Cinnamic Acid (α-CHCA) and discovered that α-CHCA has a greater effect on diminishing the invasive behavior of the cancer cells than MCT1/2 blocker SR13800. From our study, MCT4 has emerged as a prospective marker for predicting poor patient outcomes and a potential therapeutic target.

Acute kidney injury after major orthopedic surgery: A retrospective study of frequency and related risk factors.

OBJECTIVE: This study aimed to analyze the frequency of postoperative kidney injury, the related factors, and its effect on outcomes in major orthopedic surgery cases treated in the postanesthesia intensive care unit (PACU). METHODS: Major orthopedic surgery cases treated in the PACU were included in this study retrospectively. Demographic, operation, and anesthesia characteristics, CCI, ASA risk classes, preoperative biochemistry, and hemogram results of the patients were recorded. Postoperative serum creatinine level, urine output, renal replacement therapy requirement, and hemoglobin levels were recorded. The kidney damage of the patients was evaluated with RIFLE and AKIN criteria. Postoperative complications were recorded. RESULTS: The frequency of kidney injury in the early postoperative period was 7.1%. When only arthroplasty cases were taken, the frequency was 11%. It was determined that there was a correlation between preoperative ASA, CCI, BMI, K levels, lactate levels, and postoperative kidney damage (P <0.05). It was determined that the frequency and duration of inotropic use, the frequency and duration of noninvasive mechanical ventilation, and the duration of hospitalization increased in patients with postoperative kidney damage, and the frequency of pneumonia, wound infection, atelectasis, sepsis, arrhythmia, atrial fibrillation and mortality increased in the postoperative period (P <0.05). CONCLUSION: There is a need for further studies on the relationship between ASA, CCI, BMI, K, and lactate values and postoperative kidney damage. Postoperative kidney injury is associated with prolonged hospitalization and increased morbidity and mortality. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.

Development of Immediate Release Tablets Containing Calcium Lactate Synthetized from Black Sea Mussel Shells.

Nowadays, the use of marine by-products as precursor materials has gained great interest in the extraction and production of chemical compounds with suitable properties and possible pharmaceutical applications. The present paper presents the development of a new immediate release tablet containing calcium lactate obtained from Black Sea mussel shells. Compared with other calcium salts, calcium lactate has good solubility and bioavailability. In the pharmaceutical preparations, calcium lactate was extensively utilized as a calcium source for preventing and treating calcium deficiencies. The physical and chemical characteristics of synthesized calcium lactate were evaluated using Fourier Transform Infrared Spectroscopy, X-ray diffraction analysis and thermal analysis. Further, the various pharmacotechnical properties of the calcium lactate obtained from mussel shells were determined in comparison with an industrial used direct compressible Calcium lactate DC (PURACAL®). The obtained results suggest that mussel shell by-products are suitable for the development of chemical compounds with potential applications in the pharmaceutical domain.

Bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey fermented with lactic acid bacteria.

Microbial fermentation with lactic acid bacteria (LAB) is a natural food biopreservation method. Yellow mustard and milk whey are optimum substrates for LAB fermentation. The aim of the present study was to evaluate the bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey both with and without LAB fermentation. All extracts were subjected to a simulated digestion process. Total polyphenols, DL-3-phenyllactic acid (PLA), lactic acid, and the antioxidant activity were determined in the studied matrices before and after simulated digestion. Yellow mustard flour was significantly richer in total polyphenols, whereas significantly higher concentrations of PLA and lactic acid were observed in milk whey. Similar antioxidant activity was determined in both ingredients being in all cases strongly reduced after in vitro digestion. Higher bioaccessibility was found for polyphenols and PLA in milk whey. Transepithelial transport of total polyphenols was higher in yellow mustard flour compared to milk whey, reaching bioavailability values between 3-7% and 1-2%, respectively. PLA transepithelial transport was only significant in both fermented matrices with bioavailability around 4-6%. Transepithelial transport of lactic acid reached values of 31-34% (bioavailability ∼ 22%) and 15-78% (bioavailability ∼ 3%) in milk whey and yellow mustard flour, respectively. LAB fermentation showed beneficial effects on enriching extracts with PLA, lactic acid, and antioxidant activity, as well as increasing bioaccessibility of these acids in yellow mustard flour and total polyphenol bioavailability in milk whey. Results pointed to yellow mustard flour and milk whey as natural preservative ingredients used in the food industry, especially when fermented with LAB.

Plant Uptake of Lactate-Bound Metals: A Sustainable Alternative to Metal Chlorides.

Global agricultural intensification has prompted investigations into biostimulants to enhance plant nutrition and soil ecosystem processes. Metal lactates are an understudied class of organic micronutrient supplement that provide both a labile carbon source and mineral nutrition for plant and microbial growth. To gain a fundamental understanding of plant responses to metal lactates, we employed a series of sterile culture-vessel experiments to compare the uptake and toxicity of five metals (Zn, Mn, Cu, Ni, and Co) supplied in lactate and chloride salt form. Additionally, primary root growth in plate-grown Arabidopsis thaliana seedlings was used to determine optimal concentrations of each metal lactate. Our results suggest that uptake and utilization of metals in wheat (Triticum aestivum L.) when supplied in lactate form is comparable to that of metal chlorides. Metal lactates also have promotional growth effects on A. thaliana seedlings with optimal concentrations identified for Zn (0.5-1.0 µM), Mn (0.5-1.0 µM), Cu (0.5 µM), Ni (1.0 µM), and Co (0.5 µM) lactate. These findings present foundational evidence to support the use of metal lactates as potential crop biostimulants due to their ability to both supply nutrients and stimulate plant growth.

Blockade of CD73 using siRNA loaded chitosan lactate nanoparticles functionalized with TAT-hyaluronate enhances doxorubicin mediated cytotoxicity in cancer cells both in vitro and in vivo.

Chemotherapy drugs are still one of the first treatment options used in many cancers; however, problems such as cytotoxic side effects on normal cells after systemic administration and resistance to treatment have reduced the use of chemotherapeutics day by day. Targeted delivery of these drugs to the tumor site and sensitization of cancer cells to death induced by chemotherapy drugs are ways that can overcome the limitations of the use of these drugs. In this study, we designed and generated a novel nanocarrier composed of chitosan lactate nanoparticles (NPs) functionalized by HIV-1 derived TAT peptide (Transactivating transcriptional activator) and hyaluronate (HA) to deliver CD73 siRNA and doxorubicin to 4T1 and CT26 cancer cells, both in vivo and in vitro, as a novel combinatorial treatment strategy. The CD73 molecule plays a key role in many cancer cell behaviors such as proliferation, angiogenesis, metastasis, imunosuppression, and resistance to chemotherapy. Therefore, we decided to reduce the side effects of DOX by simultaneously transmitting CD73 siRNA and DOX by CL-TAT-HA NPs, increase the susceptibility of cancer cells to DOX-induced cell death, and stimulate anti-tumor immune responses, for the first time. These results indicated that simultaneous transfer of CD73 siRNA and DOX to cancer cells (4 T1 and CT26) increased cell death and inhibited the prolifration and spread of cancer cells. Also, the preferential aggregation of NPs in the tumor microenvironment reduced tumor growh, promoted the survival of tumor-bearing mice, and induced anti-tumor immune responses. These findings indicate that CL-TAT-HA NPs are a good candidate for targeted siRNA/drug delivery to cancer cells and the simultaneous transfer of CD73 siRNA and DOX to cancer cells using this nanocarrier can be used to treat cancer.

Encapsulation of Amikacin into Microparticles Based on Low-Molecular-Weight Poly(lactic acid) and Poly(lactic acid-co-polyethylene glycol).

The aim of this study was to fabricate novel microparticles (MPs) for efficient and long-term delivery of amikacin (AMI). The emulsification method proposed for encapsulating AMI employed low-molecular-weight poly(lactic acid) (PLA) and poly(lactic acid-co-polyethylene glycol) (PLA-PEG), both supplemented with poly(vinyl alcohol) (PVA). The diameters of the particles obtained were determined as less than 30 µm. Based on an in-vitro release study, it was proven that the MPs (both PLA/PVA- and PLA-PEG/PVA-based) demonstrated long-term AMI release (2 months), the kinetics of which adhered to the Korsmeyer-Peppas model. The loading efficiencies of AMI in the study were determined at the followings levels: 36.5 ± 1.5 µg/mg for the PLA-based MPs and 106 ± 32 µg/mg for the PLA-PEG-based MPs. These values were relatively high and draw parallels with studies published on the encapsulation of aminoglycosides. The MPs provided antimicrobial action against the Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae bacterial strains. The materials were also comprehensively characterized by the following methods: differential scanning calorimetry; gel permeation chromatography; scanning electron microscopy; Fourier transform infrared spectroscopy-attenuated total reflectance; energy-dispersive X-ray fluorescence; and Brunauer-Emmett-Teller surface area analysis. The findings of this study contribute toward discerning new means for conducting targeted therapy with polar, broad spectrum antibiotics.

Identification of Novel Histone Deacetylase 6-Selective Inhibitors Bearing 3,3,3-Trifluorolactic Amide (TFLAM) Motif as a Zinc Binding Group.

Pharmacological inhibition of histone deacetylase 6 (HDAC6) is an effective therapeutic strategy for cancer and immunological diseases. Most of the previously reported HDAC6 inhibitors have a hydroxamate group as a zinc binding group (ZBG), which coordinates to the catalytic zinc ion of HDAC6. The hydroxamate group is liable to metabolically generate mutagenetic hydroxylamine; therefore, non-hydroxamate HDAC6 inhibitors would be advantageous. In this study, to identify novel non-hydroxamate HDAC6-selective inhibitors, screening of a chemical library and the subsequent structural optimization were performed, which led to the identification of HDAC6-selective inhibitors with 3,3,3-trifluorolactic amide (TFLAM) as a novel ZBG. The identified inhibitor showed potent and selective HDAC6-inhibitory activity in cells and induced regulatory T (Treg) cell differentiation.

Danshensu inhibits the IL-1ß-induced inflammatory response in chondrocytes and osteoarthritis possibly via suppressing NF-κB signaling pathway.

PURPOSE: Osteoarthritis (OA) is the most common inflammatory disease associated with pain and cartilage destruction. Interleukin (IL)-1ß is widely used to induce inflammatory response in OA models. This study aimed to explore the role of Danshensu (DSS) in IL-1ß-induced inflammatory responses in OA. METHODS: IL-1ß was used to induce chondrocyte inflammation. Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay. IL-6, COX-2, TNF-α, and iNOS mRNA levels were detected by qRT-PCR. MMP3, MMP13, ADAMTS4, ADAMTS5, Aggrecan, Collagen, p-IκBα, and p-p65 protein levels were detected by Western blot. An OA mouse model was established by surgical destabilization of the medial meniscus (DMM), and the Osteoarthritis Research Society International (OARSI) score was evaluated by H&E staining. RESULTS: DSS did not affect the levels of inflammatory indicators including IL-6, COX-2, TNF-α, iNOS, PEG2, and NO but suppressed COX-2 and iNOS protein expression in IL-1ß treated chondrocytes. In addition, DSS downregulated IL-1ß-enhanced expression of MMP3, MMP13, ADAMTS4, and ADAMTS5 and upregulated aggrecan and collagen expression. Moreover, DSS significantly inhibited IL-1ß-induced phosphorylation of p-IκBα and p-p65 in a dose-dependent manner in chondrocytes, suggesting it plays a role in the NF-κB signaling pathway. Furthermore, DSS significantly reduced DMM-induced cartilage OARSI score in mice, further demonstrating its protective role in OA progression in vivo. CONCLUSIONS: Our study revealed the protective role of DSS in OA, suggesting that DSS might act as a potential treatment for OA.

Phenyl-Lactic Acid Is an Active Ingredient in Bactericidal Supernatants of Lactobacillus crispatus.

Lactobacillus crispatus is a well-established probiotic with antimicrobial activity against pathogens across several niches of the human body generally attributed to the production of bacteriostatic molecules, including hydrogen peroxide and lactic acid. Here, we show that the cell-free supernatants of clinical isolates of L. crispatus harbor robust bactericidal activity. We further identify phenyl-lactic acid as a bactericidal compound with properties and a susceptibility range nearly identical to that of the cell-free supernatant. As such, we hypothesize that phenyl-lactic acid is a key active ingredient in L. crispatus supernatant. IMPORTANCE Although Lactobacillus crispatus is an established commensal microbe frequently used in probiotics, its protective role in the bladder microbiome has not been clarified. We report here that some urinary isolates of L. crispatus exhibit bactericidal activity, primarily due to its ability to excrete phenyl-lactic acid into its environment. Both cell-free supernatants of L. crispatus isolates and phenyl-lactic acid exhibit bactericidal activity against a wide range of pathogens, including several that are resistant to multiple antibiotics.

Heparin-Tagged PLA-PEG Copolymer-Encapsulated Biochanin A-Loaded (Mg/Al) LDH Nanoparticles Recommended for Non-Thrombogenic and Anti-Proliferative Stent Coating.

Drug-eluting stents have been widely implanted to prevent neointimal hyperplasia associated with bare metal stents. Conventional polymers and anti-proliferative drugs suffer from stent thrombosis due to the non-selective nature of the drugs and hypersensitivity to polymer degradation products. Alternatively, various herbal anti-proliferative agents are sought, of which biochanin A (an isoflavone phytoestrogen) was known to have anti-proliferative and vasculoprotective action. PLA-PEG diblock copolymer was tagged with heparin, whose degradation releases heparin locally and prevents thrombosis. To get a controlled drug release, biochanin A was loaded in layered double hydroxide nanoparticles (LDH), which are further encapsulated in a heparin-tagged PLA-PEG copolymer. LDH nanoparticles are synthesized by a co-precipitation process; in situ as well as ex situ loading of biochanin A were done. PLA-PEG-heparin copolymer was synthesized by esterification reaction, and the drug-loaded nanoparticles are coated. The formulation was characterized by FTIR, XRD, DSC, DLS, and TEM. In vitro drug release studies, protein adhesion, wettability, hemocompatibility, and degradation studies were performed. The drug release was modeled by mathematical models to further emphasize the mechanism of drug release. The developed drug-eluting stent coating is non-thrombogenic, and it offers close to zero-order release for 40 days, with complete polymer degradation in 14 weeks.

Triblock Copolymer Nanomicelles Loaded with Curcumin Attenuates Inflammation via Inhibiting the NF-κB Pathway in the Rat Model of Cerebral Ischemia.

AIM: Cerebral ischemic injury is one of the debilitating diseases showing that inflammation plays an important role in worsening ischemic damage. Therefore, studying the effects of some potential anti-inflammatory compounds can be very important in the treatment of cerebral ischemic injury. METHODS: This study investigated anti-inflammatory effects of triblock copolymer nanomicelles loaded with curcumin (abbreviated as NC) in the brain of rats following transient cerebral ischemia/reperfusion (I/R) injury in stroke. After preparation of NC, their protective effects against bilateral common carotid artery occlusion (BCCAO) were explored by different techniques. Concentrations of free curcumin (C) and NC in liver, kidney, brain, and heart organs, as well as in plasma, were measured using a spectrofluorometer. Western blot analysis was then used to measure NF-κB-p65 protein expression levels. Also, ELISA assay was used to examine the level of cytokines IL-1ß, IL-6, and TNF-α. Lipid peroxidation levels were assessed using MDA assay and H&E staining was used for histopathological examination of the hippocampus tissue sections. RESULTS: The results showed a higher level of NC compared to C in plasma and organs including the brain, heart, and kidneys. Significant upregulation of NF-κB, IL-1ß, IL-6, and TNF-α expressions compared to control was observed in rats after induction of I/R, which leads to an increase in inflammation. However, NC was able to downregulate significantly the level of these inflammatory cytokines compared to C. Also, the level of lipid peroxidation in pre-treated rats with 80mg/kg NC was significantly reduced. CONCLUSION: Our findings in the current study demonstrate a therapeutic effect of NC in an animal model of cerebral ischemia/reperfusion (I/R) injury in stroke through the downregulation of NF-κB-p65 protein and inflammatory cytokines.

Comparative study on morphological, rheological and functional characteristics of extruded rice starch citrates and lactates.

Two levels of chemically modified starches (starch citrates and lactates) prepared at 20% and 40% w/v concentration was subjected to extrusion to produce pregelatinized starches (PG). Starch citrates and lactates modified at 20% and 40% level were referred as (SC20 and SC40) and (SL20 and SL40), respectively. These PG starches underwent significant structural changes during extrusion as depicted by scanning electron micrographs. Native starches showed lower swelling power and water binding capacity but formed harder gels compared to chemically modified pregels. The dynamic rheology of these polymers (extruded modified starches) suggested visco-elastic property i.e. (G' > G''). Citrates demonstrated higher G' than lactates in both frequency and temperature sweep tests. Stability of storage moduli over entire temperature range confirmed that addition of citrates and lactates led to strengthening of gel structure through cross linking and esterification. Non-newtonian behavior was shown by all samples as determined through steady shear flow test with flow behavior index <1. Starch citrate (SC20-PG) demonstrated higher shear stress values. While, SC40-PG depicted anti-thixotropic behavior as measured through in-shear structural recovery measurements. On the basis of results obtained, the dual modification (chemical followed by extrusion) may impart fruitful applications in various food products.

Poly (Lactic-co-Glycolic Acid) & Tocopheryl Polyethylene Glycol Succinate Nanoparticles for the Treatment of Different Brain Cancers.

Nanotechnology and material science developments emerge in the manufacturing of various novel modes of drug delivery, which have proven scientifically promising. Polymer nanoparticles have high stability, high specificity, high drug-carrying power, control release, and potential to be used in various pathways. They usually supply hydrophilic and hydrophobic molecules with medicines. In this review, we have discussed the different types of brain tumour, different PLGA (Poly Lactic-co-Glycolic Acid) nanostructures, PLGA in brain tumour targeting, and the recent advancement of PLGA based nanoparticles. This review focused on the method of preparation of polymeric nanoparticles, the significance of EPR (Enhanced Permeability and Retention) effect with PLGA, the significance of TPGS in cancer, and discussed the pharmaceutical application of PLGA nanoparticles. We expect these polymeric nanoparticles will be very successful and efficient for disease targeting in the future and new techniques will emerge.

Pulmonaria obscura and Pulmonaria officinalis Extracts as Mitigators of Peroxynitrite-Induced Oxidative Stress and Cyclooxygenase-2 Inhibitors-In Vitro and In Silico Studies.

The Pulmonaria species (lungwort) are edible plants and traditional remedies for different disorders of the respiratory system. Our work covers a comparative study on biological actions in human blood plasma and cyclooxygenase-2 (COX-2) -inhibitory properties of plant extracts (i.e., phenolic-rich fractions) originated from aerial parts of P. obscura Dumort. and P. officinalis L. Phytochemical profiling demonstrated the abundance of phenolic acids and their derivatives (over 80% of the isolated fractions). Danshensu conjugates with caffeic acid, i.e., rosmarinic, lithospermic, salvianolic, monardic, shimobashiric and yunnaneic acids were identified as predominant components. The examined extracts (1-100 µg/mL) partly prevented harmful effects of the peroxynitrite-induced oxidative stress in blood plasma (decreased oxidative damage to blood plasma components and improved its non-enzymatic antioxidant capacity). The cellular safety of the extracts was confirmed in experimental models of blood platelets and peripheral blood mononuclear cells. COX-2 inhibitor screening evidently suggested a stronger activity of P. officinalis (IC50 of 13.28 and 7.24 µg/mL, in reaction with synthetic chromogen and physiological substrate (arachidonic acid), respectively). In silico studies on interactions of main components of the Pulmonaria extracts with the COX-2 demonstrated the abilities of ten compounds to bind with the enzyme, including rosmarinic acid, menisdaurin, globoidnan A and salvianolic acid H.

Encapsulating Polyethyleneimine-DNA Nanoplexes into PEGylated Biodegradable Microparticles Increases Transgene Expression In Vitro and Reduces Inflammatory Responses In Vivo.

Encapsulating genetic material into biocompatible polymeric microparticles is a means to improving gene transfection while simultaneously decreasing the tendency for inflammatory responses; and can be advantageous in terms of delivering material directly to the lungs via aerosolization for applications such as vaccinations. In this study, we investigated the advantages of using polymeric microparticles carrying the luciferase reporter gene in increasing transfection efficiency in the readily transfectable HEK293 cell line and the difficult to transfect RAW264.7 cell line. The results indicated that there was a limit to the ratio of nitrogen in polyethylenimine (PEI) to phosphate in DNA (N/P ratio) beyond which further increases in transgene expression no longer, or only marginally, occurred. Microparticles encapsulating PEI:DNA nanoplexes induced cellular toxicity in a dose-dependent manner. PEGylation increased transgene expression, likely related to enhanced degradation of particles. Furthermore, intra-tracheal instillation in rats allowed us to investigate the inflammatory response in the lung as a function of PEGylation, porosity, and size. Porosity did not influence cell counts in bronchoalveolar lavage fluid in the absence of PEG, but in particles containing PEG, non-porous particles recruited fewer inflammatory cells than their porous counterparts. Finally, both 1 µm and 10 µm porous PLA-PEG particles recruited more neutrophils than 4 µm particles. Thus, we have shown that PEGylation and lack of porosity are advantageous for faster release of genetic cargo from microparticles and a reduced inflammatory response, respectively.

Three salvianolic acids inhibit 2019-nCoV spike pseudovirus viropexis by binding to both its RBD and receptor ACE2.

Since December 2019, the new coronavirus (also known as severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2, 2019-nCoV])-induced disease, COVID-19, has spread rapidly worldwide. Studies have reported that the traditional Chinese medicine Salvia miltiorrhiza possesses remarkable antiviral properties; however, the anti-coronaviral activity of its main components, salvianolic acid A (SAA), salvianolic acid B (SAB), and salvianolic acid C (SAC) is still debated. In this study, we used Cell Counting Kit-8 staining and flow cytometry to evaluate the toxicity of SAA, SAB, and SAC on ACE2 (angiotensin-converting enzyme 2) high-expressing HEK293T cells (ACE2h cells). We found that SAA, SAB, and SAC had a minor effect on the viability of ACE2h cells at concentrations below 100 µM. We further evaluated the binding capacity of SAA, SAB, and SAC to ACE2 and the spike protein of 2019-nCoV using molecular docking and surface plasmon resonance. They could bind to the receptor-binding domain (RBD) of the 2019-nCoV with a binding constant (KD ) of (3.82 ± 0.43) e-6 M, (5.15 ± 0.64)e-7 M, and (2.19 ± 0.14)e-6 M; and bind to ACE2 with KD (4.08 ± 0.61)e-7 M, (2.95 ± 0.78)e-7 M, and (7.32 ± 0.42)e-7 M, respectively. As a result, SAA, SAB, and SAC were determined to inhibit the entry of 2019-nCoV Spike pseudovirus with an EC50 of 11.31, 6.22, and 10.14 µM on ACE2h cells, respectively. In conclusion, our study revealed that three Salvianolic acids can inhibit the entry of 2019-nCoV spike pseudovirus into ACE2h cells by binding to the RBD of the 2019-nCoV spike protein and ACE2 protein.

Encapsulation and Controlled Release of a Camptothecin Prodrug from Nanocarriers and Microgels: Tuning Release Rate with Nanocarrier Excipient Composition.

Nanocarriers (NCs) are an attractive class of vehicles for drug delivery with the potential to improve drug efficacy and safety, particularly for intravenous parenteral delivery. Many therapeutics remain challenging to formulate in NCs due to their intrinsic solubilities that frustrate NC loading or result in too rapid release in vivo. Therapeutic conjugate approaches that alter the solubility of a conjugate "prodrug" have been used to enable NC formation and controlled release from NCs using labile linker chemistry. A limitation of this approach has been that a different linker chemistry must be used to produce an adjustable release rate for a single therapeutic. We report on a new approach where the therapeutic conjugate hydrolysis rates are varied by adjusting the excipient formulation of the NC core, not the conjugate linker chemistry. A hydrophobic therapeutic conjugate of camptothecin (PROCPT) is synthesized by conjugating camptothecin (CPT) with an acid derivative of α-tocopherol (vitamin E). The PROCPT compound can be loaded to 50% wt in poly(lactic acid)-block-poly(ethylene glycol) (PLA-b-PEG)-stabilized NCs produced by Flash NanoPrecipitation with particle diameters between 60 and 80 nm. Co-loading a zwitterionic lipid, 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine, from 0 to 67% core loading tunes the PROCPT hydrolysis from no observable therapeutic release over 200 h to therapeutic conjugate half-life times of 31 h. For a single therapeutic conjugate molecule, the hydrolysis rate can be tuned by modifying the NC formulation with different excipient concentrations. NCs containing a 50% core loading of PROCPT were lyophilized and encapsulated in a PEG hydrogel matrix to make microparticles for depot delivery with an average diameter of 65 ± 10 µm that provide a sustained, first-order release of CPT with a therapeutic conjugate half-life of 240 h. These results demonstrate a new approach to the formulation of therapeutic NCs with variable release profiles using a single molecular entity therapeutic conjugate.

Effects of zinc sulfate and zinc lactate on the properties of tilapia (Oreochromis Niloticus) skin collagen peptide chelate zinc.

In this study, the properties difference of Tilapia (Oreochromis Niloticus) skin collagen peptide chelate zinc prepared by zinc sulfate (P-Zn-S) and zinc lactate (P-Zn-L) were investigated. The results indicated that compared with P-Zn-L, P-Zn-S exhibited higher Zn-chelating capacity and different structural morphology, which may closely relate to the composition amino acid of Asp, Glu, His, Lys, Arg, Cys and Pro. FTIR and UV-Vis analysis indicated that different zinc sources could influence the metal ligands and the types of amino acid residues which were involved in chelation reaction. P-Zn-L exhibited better zinc solubility and had higher dialyzable zinc than P-Zn-S, indicating that P-Zn-L had better zinc bioaccessibility. These results suggested that P-Zn-L with a granular structure could reduced gastric stability, promoted intestinal release, and was beneficial to zinc absorption, which can be used as dietary zinc carriers.