Pathologic HIF1α signaling drives adipose progenitor dysfunction in obesity

Adipose precursor cells (APCs) exhibit regional variation in response to obesity, for unclear reasons. Here, we reveal that HIFα-induced PDGFRβ signaling within murine white adipose tissue (WAT) PDGFRβ⁺ cells drives inhibitory serine 112 (S112) phosphorylation of PPARγ, the master regulator of adipogenesis. Levels of PPARγ S112 phosphorylation in WAT PDGFRβ⁺ cells are depot dependent, with levels of PPARγ phosphorylation in PDGFRβ⁺ cells inversely correlating with their capacity for adipogenesis upon high-fat-diet feeding. HIFα suppression in PDGFRβ⁺ progenitors promotes subcutaneous and intra-abdominal adipogenesis, healthy WAT remodeling, and improved metabolic health in obesity. These metabolic benefits are mimicked by treatment of obese mice with the PDGFR antagonist Imatinib, which promotes adipocyte hyperplasia and glucose tolerance in a progenitor cell PPARγ-dependent manner. Our studies unveil a mechanism underlying depot-specific responses of APCs to high-fat feeding and highlight the potential for APCs to be targeted pharmacologically to improve metabolic health in obesity.

Keel-bone fractures are associated with bone quality differences in laying hens

This study aimed to investigate the relationship between bone quality in terms of metabolism, homeostasis of elements, bone mineral density (BMD), and microstructure and keel-bone fractures in laying hens (Gallusgallusdomesticus). One hundred and twenty 17 week old Lohmann White laying hens with normal keel bones were individually housed in furnished cages for 25 weeks. Birds were then euthanased and dissected to assess keel-bone status at 42 weeks. Serum and keel-bone samples from normal keel (NK) and fractured keel (FK) hens were collected to determine the previously mentioned bone quality parameters. The results showed FK hens to have higher levels of the components of osteocalcin, greater alkaline phosphatase activity in serum and keel bones, and greater tartrate-resistant acid phosphatase (TRAP) activity in keel bones, compared to NK hens. Additionally, FK hens also had higher concentrations of Li, B, K, Cu, As, Se, Sn, Hg, and Pb, but lower concentrations of Na, P, and Ca. Moreover, FK hens showed decreased bone microstructural parameters including bone volume/tissue volume, trabecular number, degree of anisotropy, connectivity density, and BMD, but increased trabecular separation. Meanwhile, no differences were detected in serum TRAP activity, trabecular thickness, bone surface, or bone surface/bone volume. Results showed laying hens with keel-bone fractures to have differences in bone metabolism, elements of homeostasis, bone microstructure parameters, and BMD. These results suggest that keel-bone fractures may be associated with bone quality.

Adiponectin, Leptin and Cardiovascular Disorders

The landmark discoveries of leptin and adiponectin firmly established adipose tissue as a sophisticated and highly active endocrine organ, opening a new era of investigating adipose-mediated tissue crosstalk. Both obesity-associated hyperleptinemia and hypoadiponectinemia are important biomarkers to predict cardiovascular outcomes, suggesting a crucial role for adiponectin and leptin in obesity-associated cardiovascular disorders. Normal physiological levels of adiponectin and leptin are indeed essential to maintain proper cardiovascular function. Insufficient adiponectin and leptin signaling results in cardiovascular dysfunction. However, a paradox of high levels of both leptin and adiponectin is emerging in the pathogenesis of cardiovascular disorders. Here, we (1) summarize the recent progress in the field of adiponectin and leptin and its association with cardiovascular disorders, (2) further discuss the underlying mechanisms for this new paradox of leptin and adiponectin action, and (3) explore the possible application of partial leptin reduction, in addition to increasing the adiponectin/leptin ratio as a means to prevent or reverse cardiovascular disorders.

Defects and plasticity in ultrastrong supercrystalline nanocomposites

Supercrystalline nanocomposites are nanoarchitected materials with a growing range of applications but unexplored in their structural behavior. They typically consist of organically functionalized inorganic nanoparticles arranged into periodic structures analogous to crystalline lattices, including superlattice imperfections induced by processing or mechanical loading. Although featuring a variety of promising functional properties, their lack of mechanical robustness and unknown deformation mechanisms hamper their implementation into devices. We show that supercrystalline materials react to indentation with the same deformation patterns encountered in single crystals. Supercrystals accommodate plastic deformation in the form of pile-ups, dislocations, and slip bands. These phenomena occur, at least partially, also after cross-linking of the organic ligands, which leads to a multifold strengthening of the nanocomposites. The classic shear theories of crystalline materials are found to describe well the behavior of supercrystalline nanocomposites, which result to feature an elastoplastic behavior, accompanied by compaction.

Adipose ABHD6 regulates tolerance to cold and thermogenic programs

Enhanced energy expenditure in brown (BAT) and white adipose tissues (WAT) can be therapeutic against metabolic diseases. We examined the thermogenic role of adipose α/β-hydrolase domain 6 (ABHD6), which hydrolyzes monoacylglycerol (MAG), by employing adipose-specific ABHD6-KO mice. Control and KO mice showed similar phenotypes at room temperature and thermoneutral conditions. However, KO mice were resistant to hypothermia, which can be accounted for by the simultaneously increased lipolysis and lipogenesis of the thermogenic glycerolipid/free fatty acid (GL/FFA) cycle in visceral fat, despite unaltered uncoupling protein 1 expression. Upon cold stress, nuclear 2-MAG levels increased in visceral WAT of the KO mice. Evidence is provided that 2-MAG causes activation of PPARα in white adipocytes, leading to elevated expression and activity of GL/FFA cycle enzymes. In the ABHD6-ablated BAT, glucose and oxidative metabolism were elevated upon cold induction, without changes in GL/FFA cycle and lipid turnover. Moreover, response to in vivo β₃-adrenergic stimulation was comparable between KO and control mice. Our data reveal a MAG/PPARα/GL/FFA cycling metabolic signaling network in visceral adipose tissue, which contributes to cold tolerance, and that adipose ABHD6 is a negative modulator of adaptive thermogenesis.

Visceral adipose adipose α/β-hydrolase domain 6 regulates cold adaptation and acts as a brake for heat production via the regulation of thermogenic glycerolipid/free fatty acid cycling.

Effects of phytase supplementation on production performance, egg and bone quality, plasma biochemistry and mineral excretion of layers fed varying levels of phosphorus

Excessive fecal excretion of phosphorus (P) has increasingly become an environmental issue due to oversupply of P in layer rations, and thus it is imperative to minimize safety margins for P to ensure the sustainability of the egg industry. In this study, a 12-week feeding trial (22 to 34 weeks of age) was conducted to evaluate the effects of phytase supplementation on production performance, plasma biochemistry, egg and bone quality and P excretion of laying hens fed various levels of non-phytate P (NPP). Forty-eight Lohmann white laying hens were randomly allocated to one of six corn-soybean meal-oat-based diets: diets containing 2.0, 2.5 or 3.0 g/kg NPP without phytase, and diets containing 1.0, 1.5 or 2.0 g/kg NPP with phytase (1 000 U/kg diet) where phytase inclusion was expected to provide 1.0 g/kg NPP to laying hens, thus making the phytase-unsupplemented treatment served as a control for the phytase-supplemented treatment accordingly. Productive performance was recorded during the experimental period. Blood and egg samples were collected, and digestibility studies were conducted at weeks 6 and 12 of the experiment. Bone mineralization was evaluated at the end of the experiment. Egg weight and egg production, feed consumption, BW and feed conversion ratio of laying hens fed lower NPP diets supplemented with phytase were comparable to those of hens fed high NPP phytase-unsupplemented controls. Eggshell thickness, specific gravity, Haugh units, tibia bone mineral density, tibia ash percent, plasma P and other biochemical parameters were not significantly different among dietary treatments. Total P intake, excretion and retention were affected by diet (P < 0.001), but its deposition in eggs was not significantly different. Contrast analysis further showed that total P excretion of phytase present vs phytase absent was averagely reduced by 40.4 mg/hen per day (P < 0.01). Moreover, total P excretion was linearly (P < 0.01) reduced with lowering dietary NPP, and this relationship was similar regardless of whether phytase was supplemented or not. The results from this study indicated that NPP levels in laying hen diets could be reduced to 1.0 g/kg (excluding the portion of NPP released by phytase) with the inclusion of phytase, without negative effects on production performance and health of the hens, thereby diminishing P excretion into environment.

SNHG16 promotes the progression of osteoarthritis through activating microRNA-93-5p/CCND1 axis

OBJECTIVE

This study aims to investigate whether SNHG16 (small nucleolar RNA host gene 16) can promote the progression of osteoarthritis (OA) by regulating the microRNA-93-5p/Cyclin D1 (CCND1) axis, thereby finding new therapeutic targets for the treatment of OA.

PATIENTS AND METHODS

A total of 23 OA patients and 23 patients undergoing lower extremity amputation were enrolled in this study. We collected their cartilage tissues from knee joint for isolating chondrocytes. The relative levels of SNHG16, CCND1 and microRNA-93-5p in cartilage tissues of OA patients and controls were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The regulatory effect of SNHG16 on proliferative potential of chondrocytes was evaluated by Cell Counting Kit-8 (CCK-8) and colony formation assay, respectively. Cell cycle progression was examined using flow cytometry. Dual-Luciferase reporter gene assay was conducted to verify the binding between SNHG16 with microRNA-93-5p and microRNA-93-5p with CCND1. Rescue experiments were performed to elucidate whether SNHG16 regulated CCND1 expression by targeting microRNA-93-5p.

RESULTS

The expressions of SNHG16 and CCND1 upregulated, while microRNA-93-5p downregulated in cartilage tissues of OA patients relative to controls. Correlation regression analyses showed a negative expression correlation between SNHG16 and microRNA-93-5p, as well as CCND1 and microRNA-93-5p in OA patients. On the contrary, SNHG16 expression was positively correlated to CCND1 expression in OA. The knockdown of SNHG16 suppressed viability, cloning ability and cell cycle progression, but induced apoptosis in chondrocytes. Dual-Luciferase reporter gene assay showed that SNHG16 could bind to microRNA-93-5p. SNHG16 knockdown markedly upregulated the expression of microRNA-93-5p. Moreover, the knockdown of microRNA-93-5p reversed the inhibited viability due to SNHG16 knockdown. Transfection of microRNA-93-5p mimics markedly inhibited CCND1 expression. Importantly, CCND1 overexpression reversed the inhibitory effect of SNHG16 knockdown on chondrocyte viability.

CONCLUSIONS

SNHG16 promotes the development of OA by regulating microRNA-93-5p/CCND1 axis.

Planktonic and sediment bacterial communities in an integrated mariculture system

An integrated multi-trophic aquaculture (IMTA) system, with one fish cage model surrounded by an island and shellfish rafts, was used in the current study. Planktonic and sediment bacterial communities in the IMTA system were monitored over four seasons in 2019. In both plankton and sediment samples, the most dominant phyla were Proteobacteria and Bacteroidota. Sediment bacterial samples were more similar and had higher levels of biodiversity than planktonic bacterial samples. Obvious seasonal variations were found in plankton samples, but not in sediment samples. No obvious inter-site variations in planktonic and sediment bacteria (fish cages, shellfish rafts and control sites) were found and the results suggested that no obvious impact of feeding operations in fish culture cage model on bacterial communities in the IMTA system was observed in this study. Based on the sequence data, some faecal indicator bacteria and potentially pathogenic bacterial species were detected. According to the results, the bacterial water quality in the IMTA system was acceptable. PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) analysis revealed that the primary difference in potential functional roles of planktonic and sediment bacteria was amino acid transport and metabolism, which was active in different seasons.

[Spatio-temporal patterns of Oncomelania hupensis snail habitats in Suzhou, Wuxi and Changzhou cities along the Taihu Lake region]

OBJECTIVE

To investigate the spatio-temporal distribution characteristics of Oncomelania hupensis snail habitats in three cities of Suzhou, Wuxi and Changzhou along the Taihu Lake region, so as to provide technical supports for establishing a sensitive and highly effective surveillance and forecast system for schistosomiasis.

METHODS

Snail distribution data were collected from Suzhou, Wuxi and Changzhou cities from 1950 to 2018, and the changing trend for snail habitats were described over years. In addition, the clusters of snail habitats were detected using Kernel density analysis and SaTScan space-time scan analysis.

RESULTS

The number of snail habitats appeared a single-peak distribution in Suzhou, Wuxi and Changzhou cities from 1950 to 2018, which peaked in 1970 and then declined rapidly. There were 62.68% of snail habitats eliminated within 10 years after identification, of which 38.24% were eliminated at the year of identification. Kernel density analysis and SaTScan space-time scan analysis revealed that high-density clusters of snail habitats were mainly distributed in Kunshan City, Wuzhong District and Xiangcheng District from 1970 to 1980, and in Yixing City in 1990; since then, the clusters gradually shrank, and overall appeared a move from northeast to west of Taihu Lake. A total of 4 new clusters were detected after 1970, as revealed by space-time scanning of snail habitats. In current snail habitats, emerging snail habitats are mainly identified in Huqiu District (Dongzhu Town), Wuzhong District (Guangfu Town), Taicang City (Shaxi Town) and Jintan District, and re-emerging snail habitats are scattered in 7 districts.

CONCLUSIONS

The distribution of snail habitats are spatio-temporal aggregation in Suzhou, Wuxi and Changzhou cities. The monitoring and prediction of emerging and re-emerging snail habitats are the key points in the future.

[Establishment of the gene detection method of Schistosoma mansoni based on the recombinase-aided isothermal amplification assay]

OBJECTIVE

To establish a recombinase-aided isothermal amplification (RAA) assay for nucleic acid detection of Schistosoma mansoni.

METHODS

The 121 bp highly-repeated sequence of S. mansoni was selected as the target gene fragment to be detected. The primers and fluorescent probes were designed using the Amplfix software, and a fluorescent RAA assay was established and optimized. The fluorescent RAA assay was performed to detect gradient diluent recombinant plasmids containing target gene fragment and different concentrations of S. mansoni genomic DNA to determine the sensitivity, and this assay was applied to detect the genomic DNA of S. japonicum, S. haematobium, Ancylostoma duodenale and Clonorchis sinensis to evaluate the specificity.

RESULTS

A fluorescent RAA assay was successfully established, which was effective to amplify the specific gene fragments of S. mansoni within 20 min at 39 ℃. The minimum detectable limit of the fluorescent RAA assay was 10 copies/μL using recombinant plasmids as templates and 0.1 fg/μL using S. mansoni genomic DNA samples as templates. The fluorescent RAA assays were all negative for detecting the genomic DNA from S. japonicum, S. haematobium, A. duodenale and C. sinensis.

CONCLUSIONS

A novel fluorescent RAA assay is successfully established, which is simple, rapid, sensitive and specific to detect genomic DNA of S. mansoni.

Horizontal sound localisation and speech perception in Bonebridge-implanted single-sided deafness patients

OBJECTIVE

This study aimed to investigate the benefit of Bonebridge devices in patients with single-sided deafness.

METHOD

Five patients with single-sided deafness who were implanted with Bonebridge devices were recruited in a single-centre study. Participants' speech perception and horizontal sound localisation abilities were assessed at 6 and 12 months post-operatively. Speech intelligibility in noisy environments was measured in three different testing conditions (speech and noise presented from the front, speech and noise presented from the front and contralateral (normal ear) side separately, and speech presented from the ipsilateral (implanted Bonebridge) side and noise from the contralateral side). Sound localisation was evaluated in Bonebridge-aided and Bonebridge-unaided conditions at different stimuli levels (65, 70 and 75 dB SPL).

RESULTS

All participants showed a better capacity for speech intelligibility in quiet environments with the Bonebridge device. The speech recognition threshold with the Bonebridge device was significantly decreased at both short- and long-term follow up in the speech presented from the ipsilateral (implanted Bonebridge) side and noise from the contralateral side condition (p < 0.05). Additionally, participants maintained similar levels of sound localisation between the Bonebridge-aided and unaided conditions (p > 0.05). However, the accuracy of localisation showed some improvement at 70 dB SPL and 75 dB SPL post-operatively.

CONCLUSION

The Bonebridge device provides the benefit of improved speech perception performance in patients with single-sided deafness. Sound localisation abilities were neither improved nor worsened with Bonebridge implantation at the follow-up assessments.

Long noncoding RNA PVT1-214 enhances gastric cancer progression by upregulating TrkC expression in competitively sponging way

OBJECTIVE

Long noncoding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) is aberrantly expressed and involved in the promotion of various cancers. However, the vital epigenetic function of PVT1-214, a transcript isoform of PVT1, in gastric cancer (GC) remains unknown. We aimed to investigate the dysregulation and detailed mechanism underlying the involvement of lncRNA PVT1-214 in GC.

PATIENTS AND METHODS

The expression of PVT1-214 in GC tissues and cell lines was detected by qRT-PCR. The relationship between increased PVT1-214 levels and the advanced clinicopathological features of tumor tissues was analyzed using a Chi-square test. The influence of PVT1-214 on the survival rate of GC cell lines was evaluated by the log-rank test. Cell lines were used to explore the carcinogenic effects of PVT1-214 in vitro and in vivo, and specific tests included cell apoptosis determined by flow cytometry, cell proliferation assayed by Cell Counting Kit-8 (CCK-8) and colony formation, and the use of these cells for mice xenograft models. Direct complementary binding was predicted by bioinformatics and verified by dual luciferase reporter assay, RNA transfection, quantitative polymerase chain reaction (qPCR), and Western blotting. Spearman's correlation coefficient was adopted to evaluate the correlation between miR-128 and PVT1-214 levels.

RESULTS

PVT1-214 expression in GC tissues and cell lines is markedly elevated. In GC patients, high expression of PVT1-214 is associated with late tumor stage, increased tumor size, and poor survival. PVT1-214 silencing represses cell proliferation and enhances apoptosis of GC cells both in vivo and in vitro. Additionally, PVT1-214 functions as a competing endogenous RNA (ceRNA) by binding to miR-128. Inhibition of miR-128 releases Tropomyosin receptor kinase C (TrkC) from the complementary binding complex, subsequently increasing the protein level of TrkC in GC cells.

CONCLUSIONS

PVT1-214-induced miR-128 repression regulates TrkC to further the progression of GC, indicating that this process will provide a promising therapeutic target in GC.