Spontaneous assembly of a class of small molecule prodrugs directed by SN38.

Small molecule self-assembling prodrugs (SAPDs) are an emerging class of amphiphilic monomers that can aggregate into supramolecular nanostructures with high drug loading identical to that of the individual prodrug. Despite great progress in creating nanodrugs via nanoprecipitation, the direct self-assembly of small molecule SAPDs in aqueous solution remains challenging, as the proper hydrophilic-hydrophobic balance and intermolecular interactions have to be rationally considered. We report a class of small molecule SAPDs by conjugating the anticancer drug SN38 as the structure-directing component with various hydrophilic auxiliaries (i.e., oligo ethylene glycol (OEG) of different lengths, amino, and carboxyl groups) via a self-immolative disulfanyl-ethyl carbonate linker. Driven by π-π interactions between SN38 units, these SAPDs spontaneously assembled into well-defined fibrous nanostructures. Variations in hydrophilic domains can robustly regulate the hydrophobicity of SAPDs, as well as the morphologies and surface features of supramolecular filaments, subsequently influencing cellular internalization behaviors. Furthermore, our study also reveals that the parent drug can be efficiently and controllably released in the presence of glutathione (GSH), exhibiting high in vitro toxicity against colorectal cancer cells. In this work, we present a delicate platform to design small molecule SAPDs that can spontaneously self-assemble into supramolecular filamentous assemblies directed by aromatic interaction of the parent drugs, providing a new strategy to optimize supramolecular drug delivery systems.

Supramolecular assembly of isomeric SN-38 prodrugs regulated by conjugation sites.

Supramolecular polymers (SPs) are an emerging class of drug transporters employed to improve drug therapy. Through the rational design of self-assembling monomers, one can optimize the properties of the resulting supramolecular nanostructures, such as size, shape, surface chemistry, release, and, therefore, biological fates. This study highlights the design of isomeric SN38 prodrugs through the conjugation of hydrophilic oligo(ethylene glycol) (OEG) with hydroxyls at positions 10 and 20 on hydrophobic SN-38. Self-assembling prodrug (SAPD) isomers 10-OEG-SN38 and 20-OEG-SN38 can self-assemble into giant nanotubes and filamentous assemblies, respectively, via aromatic associations that dominate self-assembly. Our study reveales the influence of modification sites on the assembly behavior and ability of the SN38 SAPDs, as well as drug release and subsequent in vitro and in vivo antitumor effects. The SAPD modified at position 20 exhibits stronger π-π interactions among SN38 units, leading to more compact packing and enhanced assembly capability, whereas OEG at position 10 poses steric hindrance for aromatic associations. Importantly, owing to its higher chemical and supramolecular stability, 20-OEG-SN38 outperforms 10-OEG-SN38 and irinotecan, a clinically used prodrug of SN38, in a CT26 tumor model, demonstrating enhanced tumor growth inhibition and prolonged animal survival. This study presents a new strategy of using interactions among drug molecules as dominating features to create supramolecular assemblies. It also brings some insights into creating effective supramolecular drug assemblies via the engineering of self-assembling building blocks, which could contribute to the optimization of design principles for supramolecular drug delivery systems.

Impact of Dietary Supplementation of Cysteamine on Egg Taurine Deposition, Egg Quality, Production Performance and Ovary Development in Laying Hens.

This study aimed to examine the effect of dietary cysteamine on yolk taurine content in hens during different egg production periods. In Exp. 1, China Agricultural University-3 (CAU-3) hens at the peak stage of egg production (aged 31 wks) were used to explore the effect of diets supplemented with 0.1% cysteamine on yolk taurine content, egg quality and production performance. In Exp.2, two breeds of hens (half Hy-Line Brown and half CAU-3 hens) at the late stage of egg production (68 wks) were used to investigate the influence of diets supplemented with 0, 0.02%, 0.04%, 0.08% or 0.10% cysteamine on yolk taurine content, egg quality, production performance and ovary development. In Exp.1, diets supplemented with 0.1% cysteamine significantly increased yolk taurine content (p < 0.05) without negative influence on production performance or egg quality. In Exp.2, the highest yolk taurine content was observed when cysteamine was supplemented at 0.08% (p < 0.001). However, supplemental cysteamine linearly or quadratically decreased production performance over the first few weeks of feeding, and the effects disappeared with continued feeding (p < 0.05). In conclusion, this study indicated that cysteamine supplementation benefits yolk taurine deposition in hens at both peak and late stage of egg production, but hens at the late stage of egg production show depressed production performance and egg quality.

NLRC5 potentiates anti-tumor CD8+ T cells responses by activating interferon-ß in endometrial cancer.

OBJECTIVES: NLR family CARD domain containing 5 (NLRC5) could promote major histocompatibility complex class I (MHC-I)-dependent CD8+ T cell-mediated anticancer immunity. In this study, the immunosurveillance role and underlying mechanisms of NLRC5 in endometrial cancer (EC) were characterized. METHODS: CD8+ T cells were separated from healthy women's peripheral blood by using magnetic beads. The effect of NLRC5 and interferon-ß (IFN-ß) on immunosurveillance of EC were examined through a mouse tumor model and a CD8+ T cell-EC cell coculture system after NLRC5 overexpression and IFN-ß overexpression or depletion. The effect of NLRC5 on IFN-ß expression was examined with gain- and loss-of-function experiments. RESULTS: NLRC5 overexpression in the EC cell and CD8+ T cell coculture system inhibited EC cell proliferation and migration and promoted EC cell apoptosis and CD8+ T cell proliferation. In vivo, NLRC5 overexpression increased the proportion of CD8+ T cells and inhibited EC progression. Furthermore, IFN-ß overexpression in the EC cell and CD8+ T cell coculture system activated CD8+ T cell proliferation; however, genetic depletion of IFN-ß exerted the opposite effects. In addition, NLRC5 could negatively regulate IFN-ß expression in EC cells. Mechanistically, NLRC5 potentiated the antitumor responses of CD8+ T cells to EC by activating IFN-ß. CONCLUSIONS: Taken together, our findings demonstrated that NLRC5 potentiates anti-tumor CD8+ T cells responses by activating interferon-ß in EC, suggesting that genetically escalated NLRC5 and IFN-ß may act as potential candidates for the clinical translation of adjuvant immunotherapies to patients with EC.

METTL3 facilitates immunosurveillance by inhibiting YTHDF2-mediated NLRC5 mRNA degradation in endometrial cancer.

BACKGROUND: N6-methyladenosine (m6A) methylation is the most abundant chemical posttranscriptional modification of mRNA, and it is associated with the regulation of the immune response to tumors. However, the function of m6A modification in the immune response to endometrial cancer (EC) remains unknown. Our study investigated the immunological role of methyltransferase-like 3 (METTL3) in EC and the underlying molecular mechanism. METHODS: We investigated the correlation between the expression of METTL3 and CD8 by using an endometrial tissue microarray cohort. Next, we investigated the role and mechanism of METTL3 in the immune response to EC using a mouse tumor model and a CD8+ T cell-EC cell coculture system after METTL3 overexpression or depletion. Additionally, RNA immunoprecipitation (RIP), methylated RIP, and RNA stability experiments were used to investigate the mechanism underlying the function of METTL3 in immunosurveillance of EC. RESULTS: METTL3 levels were downregulated in EC patients, low levels of METTL3 were correlated with poor prognosis in EC patients. There was a positive correlation between METTL3 expression and CD8 expression. Overexpression of METTL3 in the EC cell and CD8+ T cell coculture system inhibited EC cell proliferation, migration, and promoted CD8+ T-cell proliferation, and in vivo, METTL3 overexpression increased CD8+ T cell proportions and inhibited EC progression; however, genetic depletion of METTL3 exerted the opposite effects. NLR family CARD domain-containing 5 (NLRC5) was identified as a target of METTL3-mediated m6A modification. The degradation of NLRC5 was increased by YTH domain-containing family 2 (YTHDF2). CONCLUSIONS: Overall, METTL3, YTHDF2, and NLRC5 have potential to be the diagnostic and prognostic biomarkers for EC. METTL3 facilitated the m6A modifications of NLRC5 and inhibited its degradation through a YTHDF2-dependent mechanism in EC. Genetic overexpression of METTL3 attenuated the immune evasion of EC by promoting NLRC5-mediated immunosurveillance, suggesting that the METTL3/YTHDF2/NLRC5 axis is a promising target of immunotherapy in EC.

Oxidized corn oil changes the liver lipid metabolism of broilers by upregulating peroxisome proliferators activate receptor-α.

The objective of the following study was to investigate the effects of naturally oxidized corn oil on the antioxidant capacity and lipid metabolism of broilers. A total of 450, 1-day-old Arbor Acres male broilers were randomly divided into 5 treatments with 6 replicate cages and 15 birds/cage. The dietary treatment array consisted of ratios of naturally oxidized corn oil to non-oxidized corn oil from 0:100, 25:75, 50:50, 75:25, and 100:0, respectively. Serum, liver, and abdominal fat samples were taken at 42 d. The results showed that the liver organ index, liver catalase (CAT) activity, malondialdehyde (MDA) content, and the serum aspartate aminotransferase (AST) content had significant quadratic relationships with the ratio of naturally oxidized corn oil (P < 0.05). Inflammatory infiltrating cells appeared in the liver of the 50% and 75% oxidized corn oil group. The percentage of abdominal fat, and serum free fatty acids (FFA) content increased linearly with the increased proportion of oxidized corn oil (P < 0.05). The mRNA expression of NADH quinone oxidoreductase 1 (NQO-1), nuclear factor kappa B (NF-κB), toll-like receptor-4 (TLR-4), peroxisome proliferators activate receptor-α (PPARα), carnitine acyltransferase (CPT1), and acyl-coenzyme oxidase (ACO) of the liver increased linearly while oxidized corn oil increased in the diet (P < 0.05). Diets containing 100% oxidized corn oil significantly changed the mRNA expression of liver Caveolin compared with other treatment groups (P < 0.05). Taken together, this study demonstrated that naturally oxidized corn oil could change liver lipid metabolism and accelerate lipid deposition of broilers by upregulating PPARα.

LC3 and NLRC5 interaction inhibits NLRC5-mediated MHC class I antigen presentation pathway in endometrial cancer.

The major histocompatibility complex class I (MHC-I) transactivator, nucleotide binding oligomerization domain-like receptor family caspase recruitment domain containing 5 (NLRC5), serves as a target for immune evasion in many cancers, including endometrial cancer (EC). An inhibition of autophagy can contribute to immunotherapy by assisting the MHC-I-mediated antigen presentation in cancer. However, the underlying mechanism for autophagy-regulated MHC-I in EC remains unclear. In this study, we found that autophagy was upregulated in EC tissues when compared to that in normal endometrial tissues. MHC I and NLRC5 expressions were lower in EC endometrium than in normal endometrium. Autophagy inhibited the MHC-I genes expression in vitro. Furthermore, a negative correlation was found between NLRC5 and LC3 levels, and LC3 interacted with NLRC5 to inhibit NLRC5-mediated MHC-I antigen presentation pathway in vitro and in vivo. Thus, our findings demonstrated that an upregulation of LC3 in EC patients may contribute to tumor immune escape by restricting the NLRC5-mediated MHC-I antigen presentation pathway, signifying inhibiting LC3 and promoting NLRC5 may be a promising immunotherapy strategy in the management of EC.

Effects of naturally oxidized corn oil on inflammatory reaction and intestinal health of broilers.

This study was conducted to investigate the effects of naturally oxidized corn oil on the inflammatory reaction and intestinal health of broilers. Total 450, one-day-old Arbor Acres male broilers were randomly divided into 5 treatments with 6 replicate cages (15 birds in each replicate cage). The dietary treatment array consisted of the varying ratio of nonoxidized corn oil to naturally oxidized corn oil from 0:100, 25:75, 50:50, 75:25, and 100:0, respectively. The experimental period was 42 d. Serum, jejunum, and contents of cecum samples were taken at the age of 42 d of broilers. The results showed no significant difference in the body weight gain (BWG) with a different proportion of oxidized corn oil compared with the 0% oxidized oil group on d 42. The feed intake (FI), the concentration of immunoglobulin G (IgG), interferon-γ (IFN-γ), and interleukin-10 (IL10) in serum showed a significant quadratic response with the increase of oxidized oil concentration on d 42. The serum's concentration of IgG, IFN-γ, and IL-10 reached the highest value at 75% oxidized corn oil. In addition, the mRNA expression levels of interleukin-1ß (IL-1ß), IFN-γ, nuclear factor kappa B (NF-κB), tumor necrosis factor α (TNF-α), and myeloid differentiation factor-88 (MyD88) in the jejunum were significantly affected by different proportions of oxidized corn oil, and the gene expression levels were highest at 75% oxidized corn oil on d 42. The mRNA expression of Bcl2-associated X (Bax) in the jejunum showed a significantly quadratic curve with the increase of oxidized oil concentration, and its gene expression was the highest after adding 50% oxidized corn oil according to the regression equation on d 42. The villus height/crypt depth and goblet cells of jejunum decreased linearly with the increasing proportion of oxidized corn oil and reached the lowest point after adding 100% oxidized corn oil on d 42. The ß diversity showed the remarkable differentiation of microbial communities among 5 groups, and the microbial community of the 0% oxidized oil group was significantly separated from that of 75 and 100% oxidized oil groups in the cecum. Taken together, these results showed that a low dose of naturally oxidized corn oil is not harmful to the growth of broilers, while a high dose of oxidized corn oil will trigger the inflammatory response and adversely affect the gut health of broilers.

Androgenesis, gynogenesis, and parthenogenesis haploids in cucurbit species.

Haploids and doubled haploids are critical components of plant breeding. This review is focused on studies on haploids and double haploids inducted in cucurbits through in vitro pollination with irradiated pollen, unfertilized ovule/ovary culture, and anther/microspore culture during the last 30 years, as well as comprehensive analysis of the main factors of each process and comparison between chromosome doubling and ploidy identification methods, with special focus on the application of double haploids in plant breeding and genetics. This review identifies existing problems affecting the efficiency of androgenesis, gynogenesis, and parthenogenesis in cucurbit species. Donor plant genotypes and surrounding environments, developmental stages of explants, culture media, stress factors, and chromosome doubling and ploidy identification are compared at length and discussed as methodologies and protocols for androgenesis, gynogenesis, and parthenogenesis in haploid and double haploid production technologies.

Acceptability of early anti-retroviral therapy among HIV-infected people in Anhui province in China.

We investigated the acceptability of early anti-retroviral therapy (ART) among HIV-infected people in Anhui Province, China. A cross-sectional study was conducted in 11 convenience selected cities of Anhui Province from September 2012 to December 2013. Study participants were convenience recruited from local Centers for Disease Control and Prevention when they attended for CD4(+) cell counts testing and HIV counselling. Answers to questionnaires were obtained through face-to-face structured interviews. Factors influencing the acceptability of early ART were identified by multiple logistic regression analysis. A total of 287 HIV-infected people met the criteria and completed the survey. The acceptability of early ART was 65.2%. The results of multiple logistic regression analysis indicated that the acceptability of early ART was associated with the following factors: CD4(+) T cell count (above 750 cells/µL vs. 350 cells/µL to 550 cells/µL: OR = 0.144, P < 0.001), years of HIV diagnosis confirmation (1 year to 5 years vs. <1 year: OR = 0.418, P = 0.005; above 5 years vs. <1 year: OR = 0.160, P < 0.001), whether had sexual behaviour after HIV diagnosis confirmation (yes vs. no: OR = 2.342, P = 0.005) and the awareness of two early ART-related questions (OR = 4.101, P = 0.015; OR = 3.294, P < 0.001). In summary, the present study showed that most HIV-infected people can accept early ART. Early ART interest in Anhui HIV-infected population was high. The awareness of early ART-related knowledge in HIV-infected population was low and should be improved to achieve higher acceptability and keep adherence to early ART for HIV prevention.

Cancer risks and long-term community-level exposure to pentachlorophenol in contaminated areas, China.

Widespread use of pentachlorophenol (PCP) in schistosomiasis endemic areas had led to ubiquitous exposure to PCP and its residues. Numerous studies had revealed that occupational PCP exposure probably increased risk of cancers, but whether long-term community-level exposure to PCP generates the similarly carcinogenic effect, seldom studies focused on it. This study was to explore the cancer risks of long-term community-level PCP exposure from drinking water in a Chinese general population. Incident (2009-2012) cancer records were identified by local government national registry. And PCP concentration of raw drinking water samples in each district was measured by GC-MS/MS analysis for further division of three PCP exposure categories by interquartile range (high vs. medium vs. low). Internal comparisons were performed, and standard rate ratio was calculated to describe the relationship between PCP exposure and cancer risks by using low-exposure group as the reference group. PCP was detected in all 27 raw drinking water samples ranging from 11.21 to 684.00 ng/L. A total of 6,750 cases (4,409 male and 2,341 female cases) were identified, and age-standardized rate (world) was 154.95 per 100,000 person-years. The cancer incidence for the high-exposure group was remarkably high. Internal comparisons indicated that high PCP exposure might be positively associated with high cancer risks in the community population, particularly for leukemia (SRR = 5.93, 95 % CI = 5.24-6.71), maligant lymphoma (SRR = 2.27, 95 % CI = 2.10-2.54), and esophageal cancer (SRR = 2.42, 95 % CI = 2.35-2.50). Long-term community-level exposure to PCP was probably associated with hemolymph neoplasm, neurologic tumors, and digestive system neoplasm.

Disparities in prevalence and risk indicators of loneliness between rural empty nest and non-empty nest older adults in Chizhou, China.

AIM: The goal of the present study was to determine the disparities in prevalence and risk factors of loneliness between rural empty nest and non-empty nest older adults in Chizhou, China. METHODS: A sample of 730 participants (381 empty nest older adults and 349 non-empty nest older adults) were surveyed using the University of California at Los Angeles-Loneliness Scale, the 30-item Geriatric Depression Scale (GDS-30), the Pittsburgh Sleep Quality Index, the Social Support Rate Scale, the Perceived Social Support from Family Scale and the World Health Organization Quality of Life questionnaire abbreviated version. RESULTS: The present study showed that the mean level of loneliness did significantly differ between empty nest older adults and non-empty nest older adults (41.52 ± 6.98 vs 39.46 ± 7.38). Empty nesters had significantly higher GDS scores; by contrast, they received lower objective, subjective and family support. Family support, objective support and social interaction were associated significantly with loneliness, which was more pronounced in empty nest older adults, excluding subjective support and psychological domain. The GDS scores (ß = 0.237, P < 0.001) and age (ß = -0.114, P = 0.002) showed stronger significant associations with loneliness in empty nest older adults. CONCLUSIONS: Loneliness obviously prevails among empty nest older adults than non-empty nest older adults. Depressive symptoms showed a stronger risk of empty nest older adults being lonely. Family support was suggested as a protective factor for loneliness in both groups. These findings should be considered when developing intervention strategies to reduce loneliness.

Glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and acute leukemia risk in Asians: a meta-analysis.

The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and risk of acute leukemia in Asians remains controversial. This study was therefore designed to evaluate the precise association in 23 studies identified by a search of PubMed and several other databases, up to December 2013. Using random or fixed effects models odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Heterogeneity across studies was assessed, and funnel plots were constructed to test for publication bias. The meta-analysis showed positive associations between GST polymorphisms (GSTM1 and GSTT1 but not GSTP1) and acute leukemia risk [(OR=1.47, 95% CI 1.18-1.83); (OR=1.32, 95% CI 1.07-1.62); (OR=1.01, 95% CI 0.84-1.23), respectively] and heterogeneity between the studies. The results suggested that the GSTM1 null genotype and GSTT1null genotype, but not the GSTP1 polymorphism, might be a potential risk factors for acute leukemia. Further well-designed studies are needed to confirm our findings.

Meta-analysis of microRNA-183 family expression in human cancer studies comparing cancer tissues with noncancerous tissues.

MicroRNA-183 (miR-183) family is proposed as promising biomarkers for early cancer detection and accurate prognosis as well as targets for more efficient treatment. The results of their expression feature in cancer tissues are inconsistent and controversy still exists in identifying them as new biomarkers of cancers. Therefore, to systemically evaluate the most frequently reported cancers in which miR-183 family members were up- or down-regulated is critical for further investigation on physiological impact of its aberrant regulation in specific cancers. The published studies that compared the level of miR-183 family expression in cancer tissues with those in noncancerous tissues were reviewed by the meta-analysis with a vote-counting strategy. Among the 49 included studies, a total of 18 cancers were reported, with 11 cancers reported in at least two studies. In the panel of miR-183 family members' expression analysis, colorectal cancer and prostate cancer ranked at the top among consistently reported cancer types with up-regulated feature. Bladder cancer, lung cancer and hepatocellular carcinoma were the third most frequently reported cancer types with significant over-expression of miR-96, miR-182 and miR-183 respectively. Breast cancer and gastric cancer were presented with inconsistent regulations and the members of this family had their own distinct regulated features in other different cancers. MiR-183 family, either individually or as a cluster, may be useful prognostic markers and/or therapeutic targets in several cancers. Further studies and repeat efforts are still required to determine the role of miR-183 family in various cancer progressions.