Targeting adipocytic discoidin domain receptor 2 impedes fat gain while increasing bone mass

AUTHORS

Xiaoyu Yang, Jing Li, Liting Zhao, Yazhuo Chen, Zhijun Cui, Taotao Xu, Xu Li, Shufang Wu & Yan Zhang

ABSTRACT

Obesity is closely associated with low-bone-mass disorder. Discoidin domain receptor 2 (DDR2) plays essential roles in skeletal metabolism, and is probably involved in fat metabolism. To test the potential role of DDR2 in fat and fat-bone crosstalk, Ddr2 conditional knockout mice (Ddr2Adipo) were generated in which Ddr2 gene is exclusively deleted in adipocytes by Adipoq Cre. We found that Ddr2Adipo mice are protected from fat gain on high-fat diet, with significantly decreased adipocyte size. Ddr2Adipo mice exhibit significantly increased bone mass and mechanical properties, with enhanced osteoblastogenesis and osteoclastogenesis. Marrow adipocyte is diminished in the bone marrow of Ddr2Adipo mice, due to activation of lipolysis. Fatty acid in the bone marrow was reduced in Ddr2Adipo mice. RNA-Seq analysis identified adenylate cyclase 5 (Adcy5) as downstream molecule of Ddr2. Mechanically, adipocytic Ddr2 modulates Adcy5-cAMP-PKA signaling, and Ddr2 deficiency stimulates lipolysis and supplies fatty acid for oxidation in osteoblasts, leading to the enhanced osteoblast differentiation and bone mass. Treatment of Adcy5 specific inhibitor abolishes the increased bone mass gain in Ddr2Adipo mice. These observations establish, for the first time, that Ddr2 plays an essential role in the crosstalk between fat and bone. Targeting adipocytic Ddr2 may be a potential strategy for treating obesity and pathological bone loss simultaneously.

Correlated evolution of larval development, egg size and genome size across two genera of snapping shrimp

AUTHORS

Kristin M. Hultgren, Solomon T. C. Chak, Jeremy Bjelajac, Kenneth S. Macdonald

ABSTRACT

Across plants and animals, genome size is often correlated with life-history traits: large genomes are correlated with larger seeds, slower development, larger body size and slower cell division. Among decapod crustaceans, caridean shrimps are among the most variable both in terms of genome size variation and life-history characteristics such as larval development mode and egg size, but the extent to which these traits are associated in a phylogenetic context is largely unknown. In this study, we examine correlations among egg size, larval development and genome size in two different genera of snapping shrimp, Alpheus and Synalpheus, using phylogenetically informed analyses. In both Alpheus and Synalpheus, egg size is strongly linked to larval development mode: species with abbreviated development had significantly larger eggs than species with extended larval development. We produced the first comprehensive dataset of genome size in Alpheus (n = 37 species) and demonstrated that genome size was strongly and positively correlated with egg size in both Alpheus and Synalpheus. Correlated trait evolution analyses showed that in Alpheus, changes in genome size were clearly dependent on egg size. In Synalpheus, evolutionary path analyses suggest that changes in development mode (from extended to abbreviated) drove increases in egg volume; larger eggs, in turn, resulted in larger genomes. These data suggest that variation in reproductive traits may underpin the high degree of variation in genome size seen in a wide variety of caridean shrimp groups more generally.

Bio-clickable mussel-inspired peptides improve titanium-based material osseointegration synergistically with immunopolarization-regulation

AUTHORS

Jie Suna, Yingkang Huang, Huan Zhao, Junjie Niu, Xuwei Ling, Can Zhu, Lin Wang, Huilin Yang, Zhilu Yang, Guoqing Pan, Qin Shi

ABSTRACT

Upon the osteoporotic condition, sluggish osteogenesis, excessive bone resorption, and chronic inflammation make the osseointegration of bioinert titanium (Ti) implants with surrounding bone tissues difficult, often lead to prosthesis loosening, bone collapse, and implant failure. In this study, we firstly designed clickable mussel-inspired peptides (DOPA-N3) and grafted them onto the surfaces of Ti materials through robust catechol-TiO2 coordinative interactions. Then, two dibenzylcyclooctyne (DBCO)-capped bioactive peptides RGD and BMP-2 bioactive domain (BMP-2) were clicked onto the DOPA-N3-coated Ti material surfaces via bio-orthogonal reaction. We characterized the surface morphology and biocompatibility of the Ti substrates and optimized the osteogenic capacity of Ti surfaces through adjusting the ideal ratios of BMP-2/RGD at 3:1. In vitro, the dual-functionalized Ti substrates exhibited excellent promotion on adhesion and osteogenesis of mesenchymal stem cells (MSCs), and conspicuous immunopolarization-regulation to shift macrophages to alternative (M2) phenotypes and inhibit inflammation, as well as enhancement of osseointegration and mechanical stability in osteoporotic rats. In summary, our biomimetic surface modification strategy by bio-orthogonal reaction provided a convenient and feasible method to resolve the bioinertia and clinical complications of Ti-based implants, which was conducive to the long-term success of Ti implants, especially in the osteoporotic or inflammatory conditions.

Vascular architectural patterns in clear cell renal cell carcinoma and clear cell papillary renal cell carcinoma

AUTHORS

Sofia Canete-Portillo, Maria del Carmen Rodriguez Pena, Dezhi Wang, Diego F. Sanchez, George J. Netto & Cristina Magi-Galluzzi

ABSTRACT

Renal cell carcinomas (RCC) are well-vascularized tumors. Although clear cell RCC (CCRCC) show a characteristic vascular network, some cases show overlapping features with other RCC. We aimed to evaluate vascular architectural patterns, microvessel density (MVD), and endothelial cell density (ECD) in CCRCC compared to clear cell papillary RCC (ccpRCC). Thirty-four RCC (17 CCRCC and 17 ccpRCC) were included in the study. CD34 was used to evaluate vascular architectural patterns by microscopic estimation in all cases. CD34, ERG, and Bioquant Osteo 2019 Imaging Analysis Software were used to evaluate MVD and ECD in 17 CCRCC and 15 ccpRCC. Mean MVD was 526.63 in CCRCC vs. 426.18 in ccpRCC (p = 0.16); mean ECD was 937.50 in CCRCC vs. 1060.21 in ccpRCC (p = 0.25). CD34 highlighted four distinct vascular architectural patterns: pseudoacinar, Golgi-like, lacunae, and scattered. Lacunae and pseudoacinar was the most frequent combination in CCRCC; lacunae and Golgi-like was the predominant combination among ccpRCC. Pseudoacinar was most extensive in CCRCC and least in ccpRCC; Golgi-like was predominant in ccpRCC and uncommon in CCRCC. The extent of pseudoacinar and Golgi-like vascular architectural patterns was significantly different between CCRCC and ccpRCC (p < 0.05). Pathologists acquainted with these different vascular architectural patterns may utilize them as an additional tool in the distinction of CCRCC from ccpRCC.

Mechanism of Pingyang Jiangya Formula in treating hypertension based on network pharmacology and in vivo study

AUTHORS

Liu Deguo, Li Zirong, Chen Qihua, Wang Yuhong, Xiao Changjiang

ABSTRACT

Objective

This study aimed to analyze the mechanism of action of the Pingyang Jiangya Formula (平阳降压方, PYJYF) in treating hypertension, based on network pharmacology, and to verify the subsequent predictions through animal experiments.

Methods

The active components and related target genes of PYJYF were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM), Encyclopedia of Traditional Chinese Medicine (ETCM), and DrugBank databases and available literature. The hypertension target genes were screened based on Therapeutic Target Database (TTD), GeneCards, Online Mendelian Inheritance in Man (OMIM), UniProt, and relevant literature. The component-disease-target network intersection target genes were inputted into the STRING database, and the key target genes were selected according to the degree algorithm. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore the multitarget mechanism of action and molecular regulatory network of PYJYF in the treatment of hypertension. To verify this prediction, we used PYJYF to intervene in spontaneously hypertensive rats (SHRs) and Wistar–Kyoto rats (WKY) as normal control, and the noninvasive tail artery manometry method was used to measure systolic blood pressure (SBP) in the rat tail before PYJYF intervention. After drug intervention, the SBP of each group rats were measured and compared every week. Enzyme-linked immunosorbent assay (ELISA) was used to test plasma renin, angiotensin II (Ang II), and aldosterone (Ald) levels, and hematoxylin-eosin (HE) staining was used to observe pathological damage to the renal vessels in each group of rats. Western blot and reverse transcription real-time quantitative PCR (RT-PCR) were used to detect the protein and mRNA expression levels of PI3K, AKT1, BAX, and Bcl-2, respectively.

Results

A total of 4 123 hypertension targets were obtained from related databases. From the TCMSP and chemical databases, 78 active components of PYJYF and the corresponding 401 drug targets were retrieved. Data analysis revealed that 208 drug targets directly interacted with the hypertension targets in PYJYF. The 10 targets most closely related to hypertension target proteins in PYJYF were directly retrieved from relevant databases. GO analysis revealed that 10 direct target proteins were involved in all aspects of the antihypertensive effects of PYJYF, as well as molecular biological processes, such as the regulation of blood pressure, renin-angiotensin-aldosterone system (RAAS), angiotensin-mediated ligand reactions, and biological stimulation of cardiomyocyte apoptosis. KEGG pathway enrichment analysis revealed that PYJYF directly affected 20 signaling pathways associated with hypertension. In animal experiments, PYJYF reduced the protein and mRNA levels of PI3K, Akt, and Bax and upregulated the expression of the protein and mRNA levels of Bcl-2, reduced plasma renin, Ang II, and Ald levels, improved the hyperactivity of RAAS, and significantly reduced SBP in SHRs.

Conclusion

PYJYF is effective for hypertension therapy that acts through multiple compounds and targets. The possible underlying molecular mechanism includes regulating the PI3K/Akt signaling pathway to suppress RAAS, increasing the ratio of Bcl-2/Bax proteins, and inhibiting apoptosis, thereby mediating the repair of renal and renal vascular damage caused by hypertension. These findings warrant further research for use in clinical settings.

Evaluation of osteogenic potential of Cissus quadrangularis on mandibular alveolar ridge distraction

AUTHORS

Alaa Abdelqader Altaweel, Abdel Aziz Baiomy Abdullah Baiomy, Hazem Shawky Shoshan, Hisham Abbas, Ahmed Abdel-Shakour Abdel-Hafiz, Abd El-Hamid Gaber, Amr Abdelfatah Zewail & Marwa A. M. Elshiekh

ABSTRACT

Background

This randomized clinical trial was designed to evaluate osteogenic potential of Cissus quadrangularis in alveolar distraction to facilitate implant installation.

Material and methods

Twenty patients with atrophic ridge were treated by alveolar distraction. After completing distractor activation, patients were randomly divided into two equal groups according to administered drug (placebo and Cissus quadrangularis group). After a consolidation period, distractors were removed and implants were inserted. Clinical evaluation was done to assess wound healing, and distractor and implant stability. Histological evaluation was performed at time of implant insertion. Radiographic evaluation was performed to assess bone volume and density after distraction, as well as, density and bone loss around implant.

Results

Radiographic and histological results showed that bone formation and maturation of study group were faster than that of control group. There was a significant increased bone density in distracted area and around implant in study group than control group. A significant bone loss at end of consolidation period, and around implant at end of the study was reported in control group than study group.

Conclusion

Cissus quadrangularis administration during the consolidation period is associated with increased osteogenic potential of distracted bone. The histological and radiographic findings of current study proved that Cissus quadrangularis not only enhances rate of new bone formation, but also bone density to withstand the biomechanical requirements of implant placement in a shorter time.