Potentiating humoral and cellular immunity using a novel hybrid polymer-lipid nanoparticle adjuvant for HBsAg-VLP vaccine.

Aluminium adjuvants are commonly used in vaccines to stimulate the immune system, but they have limited ability to promote cellular immunity which is necessary for clearing viral infections like hepatitis B. Current adjuvants that do promote cellular immunity often have undesired side effects due to the immunostimulants they contain. In this study, a hybrid polymer lipid nanoparticle (HPLNP) was developed as an efficient adjuvant for the hepatitis B surface antigen (HBsAg) virus-like particle (VLP) vaccine to potentiate both humoral and cellular immunity. The HPLNP is composed of FDA approved polyethylene glycol-b-poly (L-lactic acid) (PEG-PLLA) polymer and cationic lipid 1, 2-dioleoyl-3-trimethylammonium-propane (DOTAP), and can be easily prepared by a one-step method. The cationic optimised vaccine formulation HBsAg/HPLNP (w/w = 1/600) can maximise the cell uptake of the antigen due to the electrostatic adsorption between the vaccine nanoparticle and the cell membrane of antigen-presenting cells. The HPLNP prolonged the retention of the antigen at the injection site and enhanced the lymph node drainage of antigen, resulting in a higher concentration of serum anti-HBsAg IgG compared to the HBsAg group or the HBsAg/Al group after the boost immunisation in mice. The HPLNP also promoted a strong Th1-driven immune response, as demonstrated by the significantly improved IgG2a/IgG1 ratio, increased production of IFN-γ, and activation of CD4 + and CD8 + T cells in the spleen and lymph nodes. Importantly, the HPLNP demonstrated no systemic toxicity during immunisation. The advantages of the HPLNP, including good biocompatibility, easy preparation, low cost, and its ability to enhance both humoral and cellular immune responses, suggest its suitability as an efficient adjuvant for protein-based vaccines such as HBsAg-VLP. These findings highlight the promising potential of the HPLNP as an HBV vaccine adjuvant, offering an alternative to aluminium adjuvants currently used in vaccines.

Analysis of Intestinal Short-Chain Fatty Acid Metabolism Profile After Probiotics and GLP-1 Treatment for Type 2 Diabetes Mellitus.

Type 2 diabetes accounts for about 90% of diabetes patients, and the incidence of diabetes is on the rise as people's lifestyles change. Compared with GLP-1 treatment, probiotic treatment can directly regulate homeostasis of the host gut microbe, and thus homeostasis of its metabolites. Currently, the regulatory role of probiotics on intestinal metabolites after treatment of type 2 diabetes mellitus remains unclear. The purpose of this study was to investigate the therapeutic effect of probiotics on type 2 diabetes mellitus and its regulatory effect on short-chain fatty acids, which are metabolites of intestinal microorganisms. I collected feces from 15 patients with diabetes before treatment and 15 patients with type 2 diabetes after treatment with GLP-1 and probiotics. The abundance of short-chain fatty acids in feces was determined by GC-MS. Results Both GLP-1 and probiotics could improve the levels of blood glucose, urine glucose and BMI in patients with type 2 diabetes. After glP-1 treatment, two short-chain fatty acids (butyric acid and valerate acid) in intestine were significantly changed. Propionic acid and isovalerate were significantly changed after probiotic treatment. At the same time, KEGG signal pathway enrichment results showed that probiotics intervention mainly achieved the purpose of treating type 2 diabetes through regulating protein and carbohydrate metabolism. Taken together, our study shows changes in intestinal short-chain fatty acids after probiotics or GLP-1 treatment of type 2 diabetes, which will provide us with new insights into the mechanism of probiotics treatment of type 2 diabetes, as well as potential intervention targets for diabetes treatment.

Caspase-8 knockdown suppresses apoptosis, while induces autophagy and chemo-sensitivity in non-small cell lung cancer cells.

PURPOSE: Drug resistance remains a major cause of relapse and therapeutic failure in non-small cell lung cancer (NSCLC). The purpose of this investigation is to explore the relationship between caspase-8 level and chemo-sensitivity, as well as its underlying mechanism in NSCLC cells. METHODS: NSCLC cell line, A549 cells was used to investigate the influence of caspase-8 on the biological behavior in vitro. The abundance of caspase-8 in A549 cells was manipulated by transfection lentivirus containing specific caspase-8 short hairpin RNA (sh-caspase-8) and caspase-8 overexpressed plasmid. Cell viability and the percentage of apoptotic cells was quantified using cell counting kit-8 (CCK-8) assay and flow cytometry following Annexin V-FITC/PI staining, respectively. The formation of acidic vesicle organelles (AVOs) was examined by acridine orange staining and visualized under a fluorescence microscope. The mRNA and protein levels of relative genes were determined by qRT-PCR and western blotting. RESULTS: Our results indicated that cells infected with sh-caspase-8 exhibited high knockdown efficiency. Knockdown of caspase-8 significantly reduced apoptosis of A549 cells. As evidenced by the decreased number of apoptotic cells and the reduction of Bcl-2/bax ratio. Interestingly, caspase-8 knockdown also enhanced autophagy in A549 cells. Additionally, knockdown of caspase-8 reduced the doxorubicin, carboplatin, cisplatin, and etoposide sensitivity towards A549 cells. CONCLUSION: In summary, our results revealed that knockdown of caspase-8 could promote cell growth and autophagy, while reduce chemo-sensitivity and apoptotic cell death. These finding suggest caspase-8 might serve as a potential target to improve the chemo-sensitivity for NSCLC patients in clinical setting.

8-Chrysoeriol, as a potential BCL-2 inhibitor triggers apoptosis of SW1990 pancreatic cancer cells.

8-Chrysoeriol, a bioactive flavanoid, was firstly identified to bind directly to BCL-2 as BH3 mimetics by structure-based virtual ligand screening. And 3D docking model revealed the molecular basis of 8-Chrysoeriol targeting to BCL-2. The interaction between 8-Chrysoeriol and BCL-2 was further confirmed using Microscale Thermophoresis (MST) technique. Meanwhile, high expression level of antiapoptotic protein BCL-2 was detected in SW1990 pancreatic cancer cells and 8-Chrysoeriol showed obvious proapoptosis effect against SW1990 in vitro. Collectively, the results showed that 8-Chrysoeriol as a natural dietary product potentially targeting to BCL-2 could serve as a lead compound for SW1990 pancreatic cancer therapy.

The dual regulatory function of lienal peptide on immune system.

Lienal peptide (LP), extracted from the spleen of healthy calves, has been reported to be a unique immune modulator which shows notable immunomodulatory effects on immune system function. This study was designed to further investigate the immunomodulatory effect of LP in vitro and in vivo. The results showed that LP significantly decreased the LPS-induced overexpression levels of pro-inflammatory cytokines including IL-1ß, IL-15, TNF-α and MIP-1α, through the NF-κB pathway. Moreover, LP showed an immunologic enhancement effect on immunosuppressed mice which were induced by cytarabine. The percentage of activated cells for bone marrow B lymphocytes, spleen lymphocytes, NK cells and peritoneal macrophages were notably increased after LP treatment. Furthermore, the administration of LP significantly reduced DNFB-induced inflammatory cell infiltration and restored CFA-induced arthritis in rats as evidenced by decrease in paw swelling and regulation of cytokines balance in serum. In conclusion, LP has outstanding immunomodulatory activity and could be served as a potential candidate for the management of patients with immune system disorders.

Benserazide, a dopadecarboxylase inhibitor, suppresses tumor growth by targeting hexokinase 2.

BACKGROUND: Hexokinase (HK) is the rate-limiting enzyme in the first reaction of glycolysis. And Hexokinase 2 (HK2) is most closely related to malignant tumor which expresses at higher level compared with normal cells. HK2 plays a pivotal role in tumor initiation and maintenance, which provides a new target for cancer therapy. METHODS: Structure-based virtual ligand screening was used in hit identification from ZINC Drug Database. Microscale thermophoresis assay was performed to evaluate the binding affinity. Enzyme inhibition, cytotoxicity, apoptosis, intracellular ATP level, mitochondrial membrane potential (MMP), glucose uptake and lactate production experiments were undertaken in SW480 cells to identify Benz as a HK2 inhibitor. Western blot was used to test protein expression. SW480 cells xenograft mouse models were used for in vivo study. Nano-particles of Benz were prepared to improve the antitumor efficacy and tumor targeting of Benz. HPLC was used to measure the concentration of free Benz in tumor tissues. RESULTS: Benserazide (Benz), was identified as a selective HK2 inhibitor, could specifically bind to HK2 and significantly inhibit HK2 enzymatic activity in vitro. In addition, Benz reduced glucose uptake, lactate production and intracellular ATP level, and could cause cell apoptosis and an increased loss of MMP as well. In vivo study indicated that intraperitoneal (ip) injection of Benz at 300 and 600 mg/Kg suppressed cancer growth in tumor-bearing mice and no toxicity shown. To further improve the antitumor efficacy and tumor targeting of Benz, nano-particles of Benz was prepared. Liposomal Benz at 100 and 200 mg/Kg performed potent inhibitory effects on tumor-bearing mice, showing reduced dose and better efficacy. CONCLUSIONS: Our study provides a new direction for the development of Benz and its analogues as novel antitumor agents for cancer therapy.

Identification of mangiferin as a potential Glucokinase activator by structure-based virtual ligand screening.

The natural product mangiferin (compound 7) has been identified as a potential glucokinase activator by structure-based virtual ligand screening. It was proved by enzyme activation experiment and cell-based assays in vitro, with potency in micromolar range. Meanwhile, this compound showed good antihyperglycemic activity in db/db mice without obvious side effects such as excessive hypoglycaemia.

Xanthone glycosides from Swertia bimaculata with α-glucosidase inhibitory activity.

Seven new xanthone glycosides (1-7) were isolated from the n-butanol extract of Swertia bimaculata, together with six known compounds (8-13). Their structures were elucidated on the basis of extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. All the compounds were evaluated for their α-glucosidase inhibitory activities in vitro, and compounds 3, 4, and 7 exhibited significant activities to inhibit α-glucosidase. Meanwhile the effects of different substitutions on the α-glucosidase inhibitory activity of xanthone glycosides from S. bimaculata are also discussed.

Hypoglycemic Activity and Antioxidative Stress of Extracts and Corymbiferin from Swertia bimaculata In Vitro and In Vivo.

The present study was to investigate the anti-diabetic activities of Swertia bimaculata. Based on the glucose consumption of S. bimaculata extractsand different fractions (petroleum, dichloromethane, ethyl acetate, n-butanol and water extracts) in 3T3-L1 adipocyte assay, ethanol (ETH) and dichloromethane (DTH) extracts had the most effective potency. Furthermore, ETH, DTH and corymbiferin (the most abundant component of DTH) were evaluated for anti-diabetic effects in high fat and sucrose fed combined with low dose streptozocin induced diabetic rats. DTH and corymbiferin displayed remarkable anti-diabetic activities. The fasting blood glucose levels were significantly decreased, while the serum insulin levels were obviously increased. The oral glucose tolerance was also improved. The lowed serum total cholesterol, low density lipoprotein (LDL) and triglyceride levels and increased ratio of HDL (high density lipoprotein)/LDL were observed. The insulin sensitivity was improved on the basis of increased expressions of insulin-receptor substrate-2, phosphatidylinositol 3-kinase and Ser/Thr kinase AKT2. And also DTH and corymbiferin improved antioxidant capacity and carbohydrate metabolism in diabetic rats, along with the improvement of histopathology of livers and pancreatic ß cells. Corymbiferin was one of active constituents, responsible for anti-diabetic properties. Therefore, S. bimaculata could be considered as an alternative agent against diabetes mellitus.

Two new chiratane-type triterpenoids from Swertia kouitchensis.

Two rare new chiratane-type triterpenoids, kouitchenoids A and B (1, 2), together with oleanolic acid (3) and ursolic acid (4), were isolated from ethanol extract of Swertia kouitchensis. The new structures were determined by the analysis of MS and NMR data. In addition, compounds 1-4 showed moderate inhibitory activity against the α-glucosidase (with IC50 values ranging from 1,812 to 2,027 µM).

Xanthone glycoside constituents of Swertia kouitchensis with α-glucosidase inhibitory activity.

Ten new xanthone glycosides, kouitchensides A-J (1-10), and 11 known analogues were isolated from an n-butanol fraction of Swertia kouitchensis. The structures of these glycosides were determined on the basis of extensive spectroscopic data interpretation and comparison with data reported in the literature. In an in vitro test, compounds 2, 4, 5, 6, 11, 12, and 13 (IC50 values in the range 126 to 451 µM) displayed more potent inhibitory effects against α-glucosidase activity than the positive control, acarbose (IC50 value of 627 µM).

In vitro and in vivo anti-diabetic activity of Swertia kouitchensis extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Swertia kouitchensis has long been used as a folk medicine to treat hepatitis and diabetes in central-western China. Therefore, this study was aimed to evaluate the anti-diabetic activity of the plant ethanol extract. MATERIALS AND METHODS: Firstly, the extract was tested for its inhibitory activity on α-amylase and α-glucosidase in vitro. Following that, insulin secretion test in NIT-1 cell was performed. Then, oral sucrose or starch tolerance test of the extract were carried out in normal mice. After that, acute effect of the extract was executed in normal and streptozotocin-induced (60 mg/kg) diabetic mice. Eventually, long term effect of the extract was performed in diabetic mice for 4 weeks. Oral glucose tolerance test and biochemical parameters were estimated at the end of the study. RESULTS: Swertia kouitchensis extract could remarkably inhibit the activity of α-amylase and α-glucosidase and stimulate insulin secretion in vitro. And also the extract displayed anti-hyperglycemic activity, improved antioxidant capacity, ameliorated the hyperlipidemia and carbohydrate metabolism in diabetic mice. CONCLUSIONS: Swertia kouitchensis exhibits considerable anti-diabetic activity and metabolic alterations in diabetic mice. These results provide a rationale for the use of Swertia kouitchensis to treat diabetes mellitus.