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• EGCG inhibits early and terminal adipocyte differentiation via targeting MCE phase. • EGCG regulates cell cycle in sequential order at the MCE phase of adipogenesis. • EGCG inhibits MCE and terminal adipogenesis via STAT3 (Tyr705) inactivation. • HFD induces a signature change of cell cycle regulators in mouse adipose tissues. • EGCG inhibits adipogenesis and p-STAT3/cell cycle regulator expressions in vivo. Mitotic clonal expansion (MCE) is a prerequisite for preadipocyte differentiation and adipogenesis. Epigallocatechin gallate (EGCG) has been shown to inhibit preadipocyte differentiation. However, the exact molecular mechanisms are still elusive. This study investigated whether EGCG could inhibit adipogenesis and lipid accumulation by regulating the cell cycle in the MCE phase of adipogenesis and its underlying molecular mechanisms. 3T3-L1 preadipocytes were induced to differentiate by a differentiation cocktail (DMI) and were treated with EGCG (25–100 μM) for 9, 18, and 24 h to examine the effect on MCE, or eight days to examine the effect on terminal differentiation. C57BL/6 mice were fed a high-fat diet (HFD) for three months to induce obesity and were given EGCG (50 or 100 mg/kg) daily by gavage. We showed that EGCG significantly inhibited terminal adipogenesis and lipid accumulation in 3T3-L1 cells and decreased expressions of PPARγ, C/EBPα, and FASN. Notably, at the MCE phase, EGCG regulated the cell cycle in sequential order, induced G0/G1 arrest at 18 h, and inhibited the G2/M phase at 24 h upon DMI treatment. Meanwhile, EGCG regulated the expressions of cell cycle regulators (cyclin D1, cyclin E1, CDK4, CDK6, cyclin B1, cyclin B2, p16, and p27), and decreased C/EBPβ, PPARγ, and C/EBPα expressions at MCE. Mechanistic studies using STAT3 agonist Colivelin and antagonist C188–9 revealed that EGCG-induced cell cycle arrest in the MCE phase and terminal adipocyte differentiation was mediated by the inhibition of JAK2/STAT3 signaling cascades and STAT3 (Tyr705) nuclear translocation. Furthermore, EGCG significantly protected mice from HFD-induced obesity, reduced body weight and lipid accumulations in adipose tissues, reduced hyperlipidemia and leptin levels, and improved glucose intolerance and insulin sensitivity. Moreover, RNA sequencing (RNA-seq) analysis showed that the cell cycle changes in epididymal white adipose tissue (eWAT) were significantly enriched upon EGCG treatment. We further verified that EGCG treatment significantly reduced expressions of adipogenic factors, cell cycle regulators, and p-STAT3 in eWAT. EGCG inhibits MCE, resulting in the inhibition of early and terminal adipocyte differentiation and lipid accumulation, which were mediated by inhibiting p-STAT3 nucleus translocation and activation. [Display omitted] [ABSTRACT FROM AUTHOR]

• GLP attenuates CCl 4 -induced liver injury, inflammation, and fibrosis in mice. • GLP inhibits HSCs activation and collagen formation in vivo and in vitro. • GLP elicits dual effects on apoptosis in vivo (inhibit) and in vitro (promote). • GLP inhibits ECM-receptor interaction pathway including integrin expressions. • GLP alleviates liver fibrosis via suppressing the TGF-β/Smad signaling pathway. Ganoderma lucidum polysaccharide (GLP) has many biological properties, however, the anti-fibrosis effect of GLP is unknown at present. This study aimed to examine the anti-fibrogenic effect of GLP and its underlying molecular mechanisms in vivo and in vitro. Both CCl 4 -induced mouse and TGF-β1-induced HSC-T6 cellular models of fibrosis were established to examine the anti-fibrogenic effect of a water-soluble GLP (25 kDa) extracted from the sporoderm-removed spores of G. lucidum.. Serum markers of liver injury, histology and fibrosis of liver tissues, and collagen formation were examined using an automatic biochemical analyzer, H&E staining, Sirius red staining, immunohistochemistry, immunofluorescence, ELISA, Western blotting, and qRT-PCR. RNA-sequencing, enrichment pathway analysis, Western blotting, qRT-PCR, and flow cytometry were employed to identify the potential molecular targets and signaling pathways that are responsible for the anti-fibrotic effect of GLP. We showed that GLP (150 and 300 mg/kg) significantly inhibited hepatic fibrogenesis and inflammation in CCl 4 -treated mice as mediated by the TLR4/NF-κB/MyD88 signaling pathway. We further demonstrated that GLP significantly inhibited hepatic stellate cell (HSCs) activation in mice and in TGF-β1-induced HSC-T6 cells as manifested by reduced collagen I and a-SMA expressions. RNA-sequencing uncovered inflammation, apoptosis, cell cycle, ECM-receptor interaction, TLR4/NF-κB, and TGF-β/Smad signalings as major pathways suppressed by GLP administration. Further studies demonstrated that GLP elicits anti-fibrotic actions that are associated with a novel dual effect on apoptosis in vivo (inhibit) or in vitro (promote), suppression of cell cycle in vivo , induction of S phase arrest in vitro , and attenuation of ECM-receptor interaction-associated molecule expressions including integrins ITGA6 and ITGA8. Furthermore, GLP significantly inhibited the TGF-β/Smad signaling in mice, and reduced TGF-β1 or its agonist SRI-011381-induced Smad2 and Smad3 phosphorylations, but increased Samd7 expression in HSC-T6 cells. This study provides the first evidence that GLP could be a promising dietary strategy for treating liver fibrosis, which protects against liver fibrosis and HSC activation through targeting inflammation, apoptosis, cell cycle, and ECM-receptor interactions that are mediated by TGF-β/Smad signaling. [Display omitted] [ABSTRACT FROM AUTHOR]

During mammary development, the transdifferentiation of mammary preadipocytes is one of the important sources for lactating mammary epithelial cells (MECs). However, there is limited knowledge about the mechanisms of dynamic regulation of transcriptome and genome-wide DNA methylation in the preadipocyte transdifferentiation process. Here, to gain more insight into these mechanisms, preadipocytes were isolated from adipose tissues from around the goat mammary gland (GM-preadipocytes). The GM-preadipocytes were cultured on Matrigel in conditioned media made from goat MECs to induce GM-preadipocyte-to-MEC transdifferentiation. The transdifferentiated GM-preadipocytes showed high abundance of keratin 18, which is a marker protein of MECs, and formed mammary acinar-like structures after 8 days of induction. Then, we performed transcriptome and DNA methylome profiling of the GM-preadipocytes and transdifferentiated GM-preadipocytes, respectively, and the differentially expressed genes and differentially methylated genes that play underlying roles in the process of transdifferentiation were obtained. Sub-sequently, we identified the candidate transcription factors in regulating the GM-preadipocyte-to-MEC transdifferentiation by transcription factor-binding motif enrichment analysis of differentially expressed genes and differentially methylated genes. Meanwhile, the secretory proteome of GM-preadipocytes cultured in conditioned media was also detected. By integrating the transcriptome, DNA methylome, and proteome, three candidate genes, four proteins, and several epigenetic regulatory axes were further identified, which are involved in regulation of the cell cycle, cell polarity establishment, cell adhesion, cell reprogramming, and adipocyte plasticity. These findings provide novel insights into the molecular mechanism of preadipocyte transdifferentiation and mammary development. [ABSTRACT FROM AUTHOR]

As an interesting energy-absorbing structure, auxetic reentrant honeycomb has attracted much attention in recent decades. Furthermore, due to the adjustable design in the configuration of the graded auxetic reentrant honeycomb (GARH), its mechanical performances were of greater designability and controllability. In this manuscript, compressive properties of the positive gradient auxetic honeycomb (PGAH) and negative gradient auxetic honeycomb (NGAH) were both investigated under different compression velocities. Meanwhile, the negative Poisson's ratio effects on the deformation behaviours and crushing stresses of the PGAH and NGAH were systematically studied. It was found that a new shrinkage deformation mechanism existed in the NGAH, which was different from the dynamic compressive properties of the PGAH and homogeneous auxetic honeycomb in the existing studies. Besides, the energy dissipation characteristics of both the PGAH and NGAH were also investigated. The results showed that, when under the medium and high compression velocities, the energy dissipation of the NGAH were 12.1 times and 7.41 times of those in the PGAH, respectively. It could be indicated that the NGAH was an ideal energy-absorbing structure. [ABSTRACT FROM AUTHOR]