Method using a co-culture system with high-purity intramuscular preadipocytes and satellite cells from chicken pectoralis major muscle

Intramuscular fat is important in improving meat quality; however, the lack of high-purity intramuscular preadipocyte (IMP) in vitro has severely limited the in-depth research on the mutual regulation of myocytes and adipocytes in chicken. In this study, we establish a new method by combining the mature adipocyte ceiling method and the transwell co-culture system. Mature intramuscular adipocyte (MIA) and muscle satellite cell (MSC) were obtained from digested pectoralis major, and MIAs were transformed into IMPs by dedifferentiation with ceiling culture. MSCs were then purified by differential adhesion for 2 h. The results by inverted-microscope observation, MTT assay, Oil Red O staining, and q-PCR revealed that the de-differentiated cells from MIA were identified as the IMPs, and had the same the cellular morphology, the capacity on differentiation, proliferation and passage with the abdominal fat preadipocytes (P > 0.05). The applicability of the obtained IMPs in co-cultured experiment with the MSC revealed that it could meet the requirements of the experimental study. Finally, a co-culture system of IMPs and MSCs was established using a transwell chamber. The co-cultured results indicated that MSCs in the proliferative stage tend to accelerate the differentiation of IMPs to induce more fat content in co-cultured IMPs than in single-culture IMPs (P < 0.05), in the non-proliferative stage, the results tend to show the opposite (P < 0.05). The mRNA levels of related genes significantly changed in accordance with the fat content in cells. The results strongly supported the view that the established co-culture system was effective and feasible. In summary, we successfully found a new method to explore the interaction between myocytes and adipocytes of chicken. Our findings can deepen research on the regulation of chicken myocytes and adipocytes.

Expression and effect of Calpain9 gene genetic polymorphism on slaughter indicators and intramuscular fat content in chickens

Calpain 9 (CAPN9) is expressed in the stomach and small intestine. CAPN9 has regulatory roles in hypertension, heart disease, gastric mucosal defense, and kidney disease. The involvement of CAPN9 has not been reported in the development of chickens. CAPN9 mRNA was found in adipose and muscle tissue in this study. Two linkage single nucleotide polymorphisms (SNP; G7518A and C7542G) in intron 4 were screened from 160 birds of the D2 chicken line. The 2 mutation sites were associated with carcass weight, evisceration weight, abdominal fat weight (AFW), abdominal fat percentage (AFP), and breast muscle percentage (all P < 0.05). Intramuscular fat (IMF) content was not significantly different in the 3 genotypes. But, the AA(7518)/GG(7542) genotype had the highest IMF content, highest breast muscle weight, and lower AFW and AFP. Moreover, the mRNA level of CAPN9 in abdominal fat tissue was significantly different (P < 0.05 or P < 0.01) between any 2 genotypes, consistent with AFW and AFP. In summary, the expression of CAPN9 in adipose and breast muscle tissue is reported for the first time. CAPN9 affected production performance of chickens. As a marker, the linkage G7518A and C7542G polymorphisms in intron 4 of CAPN9 could affect the production traits by regulating mRNA expression. The findings concerning the marker enrich the theoretical foundation for molecular breeding of high-quality broilers.

High calcium to phosphorus ratio impairs growth and bone mineralization in Pekin ducklings

Two experiments were conducted to investigate the effect of high dietary calcium (Ca) level on growth performance, Ca and phosphorus (P) metabolism, and nutrient utilization in ducklings subjected to normal and low P levels in diets. A completely randomized design was used with a factorial arrangement of 2 total dietary P levels [normal-P (0.60%) and low-P (0.45%) groups] × 4 dietary Ca levels [low-Ca (0.55%), normal-Ca (0.75%), medium-Ca (0.95%) and high-Ca (1.15%) groups)]. Compared to normal-P group, low-P group had lower (P < 0.05) final body weight (BW), average daily gain (ADG), and average daily feed intake (ADFI) and reduced (P < 0.05) serum Ca and P levels, bone Ca, P, and ash content, and bone mineral density in ducklings during the starter period. Under the low-P group, birds from high-Ca group had lower (P < 0.05) final BW, ADG, ADFI, bone ash content, bone mineral density, and the utilization of energy, Ca, and P than those from low-Ca, normal-Ca, and medium-Ca groups. Our results indicate that high-Ca diet induced greater growth suppression and bone mineralization loss in ducklings fed a low-P diet. The aggravated negative effect of high dietary Ca level with a low P level might be related to the elevated serum alkaline phosphatase activity and the reduced utilization of energy, Ca, and P.

Safety and efficacy of telbivudine in late pregnancy to prevent mother-to-child transmission of hepatitis B virus: A multicenter prospective cohort study

Infection of hepatitis B virus (HBV) occurs in ~10% of infants of HBV-infected mothers with positive hepatitis B e antigen (HBeAg) after immunoprophylaxis. We aimed to evaluate the safety and efficacy of telbivudine used during late pregnancy for preventing mother-to-child transmission of HBV. We conducted a multicenter prospective cohort study in 5 hospitals from 2012 to 2014, which enrolled HBV-infected singleton pregnant women with positive HBeAg. By their choice, women were divided into therapy (telbivudine 600 mg/day, from gestation 28-32 weeks to 3-4 weeks postpartum) and control (no antiviral agent) groups. Infants received passive-active immunoprophylaxis and follow-up at the age of 7-14 months. Totally, 328 pregnant women were included: 149 in the telbivudine group and 179 in the control group. Baseline HBV DNA levels were similar in the 2 groups (7.43 vs 7.37 log₁₀ IU/mL, P = .711). At delivery, HBV DNA levels in the telbivudine and control groups were 3.80 and 7.26 log₁₀ IU/mL, respectively (P < .0001). Of the infants, 128 (85.9%) in the telbivudine group and 156 (87.2%) in the control group were followed up. No infant in the telbivudine group had chronic infection, while 2 (1.28%) infants in the control group did (P = .503). Three (2.34%) infants in the telbivudine group, but none in the control group, had severe congenital or developmental abnormalities (P = .090). The data indicate that telbivudine may block perinatal HBV transmission. However, larger studies are required to clarify whether anti-HBV therapy in pregnancy is associated with severe adverse effects in the foetuses and infants.

Proteomics and microscopy tools for the study of antimicrobial resistance and germination mechanisms of bacterial spores

Bacterial spores are ubiquitous in nature and can withstand both chemical and physical stresses. Spores can survive food preservation processes and upon outgrowth cause food spoilage as well as safety risks. The heterogeneous germination and outgrowth behavior of isogenic spore populations exacerbates this risk. A major unknown factor of spores is likely to be the inherently heterogeneous spore protein composition. The proteomics methods discussed here help in broadening the knowledge about spore structure and identification of putative target proteins from spores of different spore formers. Approaches to synchronize Bacillus subtilis spore formation, and to analyze spore proteins as well as the physiology of spore germination and outgrowth are also discussed. Live-imaging and fluorescence microscopy techniques discussed here allow analysis, at single cell level, of the 'germinosome', the process of spore germination itself, spore outgrowth and the spore intracellular pH dynamics. For the latter, a recently published improved pHluorin (IpHluorin) under control of the ptsG promoter is applicable. While the data obtained from such tools offers novel insight in the mechanisms of bacterial spore awakening, it may also be used to probe candidate antimicrobial compounds for inhibitory effects on spore germination and strengthen microbial risk assessment.

[Prevalence and trend of overweight and obesity in children and adolescents in Guangdong province, 2002-2012]

Objective: To investigate the prevalence and trend of overweight and obesity in children and adolescents aged 6-17 years between 2002 and 2012 in Guangdong province. Methods: A total of 7 075 children and adolescents aged 6-17 years were selected in Guangdong for nutritional survey in 2002 and a total of 2 319 children and adolescents aged 6-17 years were selected in nine counties/districts of Guangdong for nutritional survey during 2009-2012 through multi-stage random cluster sampling. The body height and weight of all the children and adolescents were measured. Results: The result of 2009-2012 survey indicated the average prevalence of overweight and obesity in the children and adolescents surveyed were 7.3% and 4.5%, respectively. The prevalence of overweight and obesity were higher in boys (8.9% and 6.5%) than in girls (5.3% and 2.2%), in rural area (9.3% and 5.6%) than in urban area (4.7% and 3.2%). Children and adolescents aged 9-11 years had a higher overweight and obesity rates compared with other age groups. Compared with 2002, except for obesity rate in urban girls, the prevalence of overweight and obesity in children and adolescents obviously increased. The increase rate was higher in rural area than urban area and in boys than in girls. Conclusions: Compared with 2002, the prevalence of overweight and obesity in children and adolescents in Guangdong obviously increased. The prevalence was much higher in boys, those living in rural area and those aged 9-11 years, thus more attention should be paid to them.

Exome sequencing identifies a TCF4 mutation in a Chinese pedigree with symmetrical acral keratoderma

BACKGROUND

Symmetrical acral keratoderma (SAK) is a rare skin disorder and its pathogenesis and inheritability are unknown.

OBJECTIVES

To investigate the inheritance and pathogenesis of SAK.

METHODS

Four SAK cases occurred in a four-generation Chinese family. Exome sequencing identified SNPs with potential SAK-related mutations, and a potentially responsible gene transcription factor 4 (TCF4) was identified. TCF4 was then sequenced in all 11 family members, and pedigree analysis was performed. Histopathology and immunohistochemistry evaluated TCF4 expression in skin lesions. The gene mutation was investigated in human keratinocytes for keratin-related protein expression.

RESULTS

A novel heterozygous missense mutation, c.85C>A (p.Pro29Thr) was found in TCF4. The mutation showed autosomal dominant inheritance and perfectly cosegregated with the SAK phenotype in all family members. In skin lesions, TCF4 was present in the cytoplasm and membranes of the basal layer, the stratum spinosum and the stratum granulosum of the epidermis. The mutant TCF4 induced overexpression of differentiation markers including KRT1, KRT14, loricrin and involucrin.

CONCLUSIONS

A SAK-related gene mutation in TCF4 may function through transcriptional regulation of keratin.

Effects of caponization and ovariectomy on objective indices related to meat quality in chickens

Capons and ovariectomized chickens are birds that have been gonadectomized to improve the meat quality. This study investigated the effects of caponization and ovariectomy on physical, chemical, and fatty acid and amino acid profiles of meat from Beijing-You chickens (a Chinese local breed) at market age (17 wk). All birds (20 capons, 20 ovariectomized, and 40 controls) were reared under the same conditions. Breast muscle fiber diameter and area were significantly smaller and the fiber density was higher in capons and ovariectomized chickens than in controls (P < 0.05). Compared with controls, caponization and ovariectomy significantly decreased breast muscle shear values and redness (a*), as well as increased yellowness (b*), hue (H*), and chroma (C*) (P < 0.05). There was significantly more intramuscular fat (IMF) in capons than in controls (P < 0.05), and there was a tendency for more inosine-5΄-monophosphate (IMP) in capons than in controls (P = 0.10). The levels of IMF and IMP in ovariectomized chickens were significantly higher than those in controls (P < 0.05). Capons and ovariectomized chickens exhibited a significantly higher content of palmitic acid (C16:0), palmitoleic acid (C16:1) and oleic acid (C18:1), together with a lower content of stearic acid (C18:0), arachidonic acid (C20:4), and lignoceric acid (C24:0) compared to controls (P < 0.05). The total saturated, monounsaturated, and polyunsaturated fatty acids as well as amino acid composition were not affected by gonadectomy (P > 0.05). Overall, this study indicates that both caponization and ovariectomy likely improve the meat quality of the breast muscle based on the objective indices of IMF, appearance (color), texture, and minor change of the fatty acid profile; ovariectomy improves flavor-related indices.

Mechanical force-mediated pathological cartilage thinning is regulated by necroptosis and apoptosis

OBJECTIVE

This study aimed to identify the mechanisms underlying mandibular chondrocyte cell death and cartilage thinning in response to mechanical force.

MATERIAL AND METHODS

An in vivo model (compressive mechanical force) and an in vitro model (TNF-α+cycloheximide) were used to induce mandibular chondrocyte necroptosis. Hematoxylin and eosin staining and transmission electron microscopy were used to assess histological and subcellular changes in mandibular chondrocyte. Immunohistochemistry, western blotting, and real-time PCR were performed to evaluate changes in necroptotic protein markers. Cell activity, mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) were examined in vitro.

RESULTS

The expression of RIP1, RIP3 and Caspase-8 in mandibular chondrocytes significantly increased after 4 days of compressive mechanical force. Furthermore, the inhibition of necroptosis by Necrostatin-1 (Nec-1) or the inhibition of apoptosis by N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD) partially restored mechanical force-mediated mandibular cartilage thinning and chondrocyte death. Moreover, a synergistic effect on cell death inhibition and mandibular cartilage thickness restoration were found when treated with Nec-1+Z-VAD. The results of the in vitro model were in line with the in vivo ones, indicating that the changes in MMP and ROS generation contributed to mandibular chondrocyte apoptosis and necroptosis.

CONCLUSION

In addition to apoptosis, necroptosis also plays critical roles in pathological changes in mandibular cartilage after compressive mechanical force stimulation, implying RIP1, a master protein that mediates both necroptosis and apoptosis, as a potential therapeutic target in temporal mandibular osteoarthritis.

Phylogenetic and paleobotanical evidence for late Miocene diversification of the Tertiary subtropical lineage of ivies (Hedera L., Araliaceae)

BACKGROUND

Hedera (ivies) is one of the few temperate genera of the primarily tropical Asian Palmate group of the Araliaceae, which extends its range out of Asia to Europe and the Mediterranean basin. Phylogenetic and phylogeographic results suggested Asia as the center of origin and the western Mediterranean region as one of the secondary centers of diversification. The bird-dispersed fleshy fruits of ivies suggest frequent dispersal over long distances (e.g. Macaronesian archipelagos), although reducing the impact of geographic barriers to gene flow in mainland species. Genetic isolation associated with geographic barriers and independent polyploidization events have been postulated as the main driving forces of diversification. In this study we aim to evaluate past and present diversification patterns in Hedera within a geographic and temporal framework to clarify the biogeographic history of the genus.

RESULTS

Phylogenetic (biogeographic, time divergence and diversification) and phylogeographic (coalescence) analyses using four DNA regions (nrITS, trnH-psbA, trnT-trnL, rpl32) revealed a complex spatial pattern of lineage divergence. Scarce geographic limitation to gene flow and limited diversification are observed during the early-mid Miocene, followed by a diversification rate increase related to geographic divergence from the Tortonian/Messinian. Genetic and palaeobotanical evidence points the origin of the Hedera clade in Asia, followed by a gradual E-W Asian extinction and the progressive E-W Mediterranean colonization. The temporal framework for the E Asia - W Mediterranean westward colonization herein reported is congruent with the fossil record. Subsequent range expansion in Europe and back colonization to Asia is also inferred. Uneven diversification among geographic areas occurred from the Tortonian/Messinian onwards with limited diversification in the newly colonized European and Asian regions. Eastern and western Mediterranean regions acted as refugia for Miocene and post-Miocene lineages, with a similar role as consecutive centers of centrifugal dispersal (including islands) and speciation.

CONCLUSIONS

The Miocene Asian extinction and European survival of Hedera question the general pattern of Tertiary regional extinction of temperate angiosperms in Europe while they survived in Asia. The Tortonian/Messinian diversification increase of ivies in the Mediterranean challenges the idea that this aridity period was responsible for the extinction of the Mediterranean subtropical Tertiary flora. Differential responses of Hedera to geographic barriers throughout its evolutionary history, linked to spatial isolation related to historical geologic and climatic constraints may have shaped diversification of ivies in concert with recurrent polyploidy.

Effects of continuous low dose infusion of lipopolysaccharide on inflammatory responses, milk production and milk quality in dairy cows

The objective of this study was to evaluate the effects of continuous low dose infusion of lipopolysaccharide (LPS) on inflammatory responses and milk production and quality in lactating dairy cows. Eight Holstein cows were assigned to two treatments in a cross-over experimental design. Cows were infused intravenously either with saline solution or with saline solution containing LPS from Escherichia coli O111:B4 at a dose of 0.01 μg LPS/kg body weight for approximately 6 hr each day during a seven-day trial. The clinical symptoms and milk production performance were observed. Milk samples were analysed for conventional components, fatty acids and amino acids. And jugular vein and mammary vein plasma samples were analysed for concentrations of cytokines and acute phase proteins. LPS infusion decreased feed intake and milk yield. An increase in body temperature was observed after LPS infusion. LPS infusion also increased plasma concentrations of interleukin-1β, serum amyloid A, LPS-binding protein, C-reactive protein and haptoglobin. LPS infusion decreased the contents of some fatty acids, such as C17:1, C18:0, C18:1n9 (trans) and C18:2n6 (trans), and most amino acids except for methionine, threonine, histidine, cysteine, tyrosine and proline in the milk. The results indicated that a continued low dose infusion of LPS can induce an inflammatory response, decrease milk production and reduce milk quality.

Circulating myeloid-derived suppressor cells predict disease activity and treatment response in patients with immune thrombocytopenia

Immune thrombocytopenia (ITP) is a disease characterized by isolated thrombocytopenia. Abnormal effector T cell activation is an important mechanism in the pathogenesis of ITP. Regulatory T cells (Treg) have a strong immunosuppressive function for T cell activation and their importance in the pathophysiology and clinical treatment of ITP has been confirmed. Myeloid-derived suppressor cells (MDSCs) are other immunosuppressive cells, which can also suppress T cell activation by secreting arginase, iNOS and ROS, and are essential for Treg cells’ differentiation and maturation. Therefore, we speculate that MDSCs might also be involved in the immune-dysregulation mechanism of ITP. In this study, we tested MDSCs and Treg cells in peripheral blood samples of twenty-five ITP patients and ten healthy donors. We found that MDSCs and Treg cells decreased simultaneously in active ITP patients. Relapsed ITP patients showed lower MDSCs levels compared with new patients. All patients received immunosuppressive treatment including dexamethasone alone or in combination with intravenous immune globulin. We found that MDSCs’ level after treatment correlated with platelet recovery. Our study is the first that focused on MDSCs’ role in ITP. Based on our results, we concluded that circulating MDSCs could predict disease activity and treatment response in ITP patients. This preliminary conclusion indicates a substantial significance of MDSCs in the pathophysiology and clinical treatment of ITP, which deserves further investigation.

Impact of age on plasma vaspin concentration in a group of normal Chinese people

PURPOSE

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipocytokine with insulin-sensitizing effects. Accumulating data implied that vaspin represents a compensatory mechanism but it is unknown how vaspin change during ageing. This study was designed to examine the correlation between plasma vaspin and age in a group of normal Chinese people.

METHODS

A total of 191 Chinese volunteers aged 19-80 years were enrolled into four groups based upon age quartiles (19-35, 36-50, 51-65 and 66-80 years). Demographic, anthropometric, metabolic covariates, vaspin and adiponectin were measured. The influence of age on plasma vaspin was analysed using SPSS 13.0.

RESULTS

Vaspin increased with ageing, with mean vaspin levels (ng/mL) of 1.01 ± 2.25, 1.67 ± 2.95, 2.05 ± 3.46 and 2.40 ± 3.06 for those between quartile ages 19-35, 36-50, 51-65 and 66-80 years. When divided into subgroups, vaspin increased with increasing age for both sexes, both insulin resistance and non-insulin resistance subjects and both obese and lean subjects. In univariate analyses, vaspin plasma level positively associated with age (r = 0.215, p = 0.003), adiponectin, insulin, homoeostasis model of assessment for insulin resistance index and waist-hip ratio in the whole population. The correlation between ageing and increasing vaspin remained significant after multivariate adjustments for factors such as sex, body mass index, waist-hip ratio, indices of glucose metabolism, white blood cell, lipid profile and adiponectin. Stepwise multiple regression analysis showed that age contributed 7.6 % on plasma vaspin level.

CONCLUSION

Vaspin level increased with ageing, independent of sex, indices of glucose metabolism, lipid profile and other markers of adiposity.

Comparison of Insulin Resistance and β-Cell Dysfunction Between the Young and the Elderly in Normal Glucose Tolerance and Prediabetes Population: A Prospective Study

Insulin resistance and β-cell function are different between the young and elderly diabetes individuals, which are not well elaborated in the nondiabetic persons. The aims of this study were to compare insulin resistance and β-cell function between young and old adults from normal glucose tolerance (NGT) to prediabetes [which was subdivided into isolated impaired fasting glucose (i-IFG), isolated impaired glucose tolerance (i-IGT), and a combination of both (IFG/IGT)], and compare the prevalence of diabetes mellitus (DM) in the above prediabetes subgroups between different age groups after 3 years. A total of 1 374 subjects aged below 40 or above 60 years old with NGT or prediabetes were finally included in this study. Insulin resistance and β-cell function from homeostasis model assessment (HOMA) and interactive, 24-variable homeostatic model of assessment (iHOMA2) were compared between different age groups. The rate of transition to diabetes between different age groups in all pre-diabetes subgroups was also compared. Compared with the old groups, young i-IFG and IFG/IGT groups exhibit higher log HOMA-IR and log HOMA2-S, whereas the young i-IGT groups experienced comparable log HOMA-IR and log HOMA2-S when compared with old i-IFG and IFG/IGT groups. Three prediabetes subgroups all had similar log HOMA-B and log HOMA2-B between different age groups. In addition, the prevalence of diabetes in young i-IFG was statistically higher than that in old i-IFG after 3 years. Age is negatively related to log HOMA2-B in both age groups. Considering an age-related deterioration of β-cell function, young i-IFG, young i-IGT, and young IFG/IGT all suffered a greater impairment in insulin secretion than the old groups. Young i-IFG and IFG/IGT have more severe insulin resistance than the old groups. In addition, young i-IFG characterized with a higher incidence of DM than the old i-IFG. These disparities highlight that the prevention to slow progression from prediabetes to type 2 diabetes should be additionally focused in young prediabetes individuals, especially young i-IFG.