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Overexpression of HER2 is associated with cancer phenotypes, such as proliferation, survival, metastasis and angiogenesis, and has been validated as a therapeutic target. However, only a portion of patients benefited from anti-HER2 treatments, and many would develop resistance. A more effective HER2 targeted therapeutics is needed. Here, we adopted a prodrug system that uses 5-fluorocytosine (5-FC) and a HER2-targeting scaffold protein, Z HER2:2891 , fused with yeast cytosine deaminase (Fcy) to target HER2-overexpressing cancer cells and to convert 5-FC to a significantly more toxic chemotherapeutic, 5-fluorouracil (5-FU). We cloned the coding gene of Z HER2:2891 and fused with those of ABD (albumin-binding domain) and Fcy. The purified Z HER2:2891 -ABD-Fcy fusion protein specifically binds to HER2 with a Kd value of 1.6 nM Z HER2:2891 -ABD-Fcy binds to MDA-MB-468, SKOV-3, BT474, and MC38-HER2 cells, which overexpress HER2, whereas with a lower affinity to HER2 non-expresser, MC38. Correspondingly, the viability of HER2-expressing cells was suppressed by relative low concentrations of Z HER2:2891 -ABD-Fcy in the presence of 5-FC, and the IC 50 values of Z HER2:2891 -ABD-Fcy for HER2 high-expresser cells were approximately 10–1000 fold lower than those of non-HER2-targeting Fcy, and ABD-Fcy. This novel prodrug system, Z HER2:2891 -ABD-Fcy/5-FC, might become a promising addition to the existing class of therapeutics specifically target HER2-expressing cancers. • HER2 is a valid cancer therapeutic target. • Resistance to current treatments occurs in significant portion of patients. • Z HER2:2891 -ABD-Fcy with HER2-targeting and 5-FC converting activities could be purified. • Z HER2:2891 -ABD-Fcy/5-FC potently inhibits viability of HER2-expressing cells. [ABSTRACT FROM AUTHOR]

Inflammation can contribute to the initiation and progression of atrial fibrillation (AF), and pinocembrin can suppress downstream inflammatory cytokine production by inhibiting the inflammation pathway. In our previous studies, pinocembrin was also beneficial in ameliorating cardiac arrhythmia in different models of rats, such as depression, myocardial infarction, and heart failure. This study aims to investigate the effect of pinocembrin on the susceptibility to AF in isoproterenol-induced rats. Rats were randomly divided into four groups. Pinocembrin was injected through the tail vein. Isoproterenol was treated by intraperitoneal injection for one week (5 mg/kg/day). We evaluated the susceptibility to AF by atrial electrophysiological experiments. Masson staining was used to evaluate the fibrosis area. The protein levels of connexin (Cx) 40, Cav1.2, Kv4.2, collagen I, collagen III, α-SMA, transforming growth factor (TGF)-β, NLRP3, caspase 1, and interleukin (IL)-1β were detected by western blot. Our data demonstrated that pinocembrin could prolong the atrial effective refractory period (ERP) and action potential duration (APD), and decrease AF inducibility. Isoproterenol increased the expression of Cav1.2 and Kv4.2 ion channels whereas pinocembrin could alleviate this change. Pinocembrin could reduce the fibrosis area, fibrosis-related protein collagen I, collagen III, α-SMA, and TGF-β and upregulate gap junction protein Cx40. In addition, pinocembrin reduced the expression of NLRP3, caspase 1, and IL-1β. Our study indicated that pinocembrin was beneficial to alleviate atrial electrical remodeling and fibrosis. Accompanied the downregulation of ion channels and upregulation of gap junction protein Cx40. Pinocembrin may produce these effects by inhibiting the NLRP3 pathway. • Pinocembrin ameliorated isoproterenol-induced atrial electrical remodeling. • Pinocembrin decreased isoproterenol-induced atrial fibrosis. • Pinocembrin decreased atrial fibrillation susceptibility in isoproterenol-induced rats. • Pinocembrin suppressed isoproterenol-induced inflammatory responses. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD), a chronic liver condition and metabolic disorder, has emerged as a significant health issue worldwide. D-mannose, a natural monosaccharide widely existing in plants and animals, has demonstrated metabolic regulatory properties. However, the effect and mechanism by which D-mannose may counteract NAFLD have not been studied. In this study, network pharmacology followed by molecular docking analysis was utilized to identify potential targets of mannose against NAFLD, and the leptin receptor-deficient, genetically obese db/db mice was employed as an animal model of NAFLD to validate the regulation of D-mannose on core targets. As a result, 67 targets of mannose are predicted associated with NAFLD, which are surprisingly centered on the mechanistic target of rapamycin (mTOR). Further analyses suggest that mTOR signaling is functionally enriched in potential targets of mannose treating NAFLD, and that mannose putatively binds to mTOR as a core mechanism. Expectedly, repeated oral gavage of supraphysiological D-mannose ameliorates liver steatosis of db/db mice, which is based on suppression of hepatic mTOR signaling. Moreover, daily D-mannose administration reduced hepatic expression of lipogenic regulatory genes in counteracting NAFLD. Together, these findings reveal D-mannose as an effective and potential NAFLD therapeutic through mTOR suppression, which holds translational promise. • Network pharmacology identifies targets of mannose against NAFLD centered on mTOR. • Mannose putatively binds to the mTOR protein as a core mechanism in treating NAFLD. • Daily oral administration of D-mannose ameliorates liver steatosis of db/db mice. • D-mannose reduced lipogenic regulatory gene expression based on mTOR suppression. [ABSTRACT FROM AUTHOR]

Abstract Stromal interaction molecule 1 (STIM1) is a transmembrane endoplasmic reticulum protein, and it serves as a Ca2+ sensor and activator of store-operated Ca2+ entry (SOCE). We have previously identified STIM1 in the proteome profile of mice neonatal testes, revealing STIM1 to be associated with neonatal testicular development. Here, to further explore the location and function of STIM1 in mice testes, we studied the effect of Stim1 gene knockdown on neonatal testicular development by testicular culture. Our results revealed that STIM1 was primarily located in Sertoli cells. Knockdown of Stim1 gene using morpholino in neonatal testis caused the mislocation of Sertoli cells and loss of germ cells, which were associated with the aberrant reactive oxygen species (ROS) activation, while inhibition of ROS could partly rescue the phenotypes caused by Stim1 gene knockdown. In conclusion, our study suggests that STIM1 can maintain neonatal testicular development by inhibiting ROS activation. Highlights • STIM1 is found in Sertoli cells and associated with neonatal testicular development. • STIM1 is required for Sertoli cell orientation and germ cell survival. • Stim1 knockdown in neonatal testis altered the testicular phenotype and induced ROS. • ROS inhibition partially rescued the Stim1 knockdown phenotype in neonatal testes. • STIM1 can maintain neonatal testicular development by inhibiting ROS activation. [ABSTRACT FROM AUTHOR]

This work reports the 13 C-assisted metabolic flux analysis of Haladaptatus paucihalophilus , a halophilic archaeon possessing an intriguing osmoadaption mechanism. We showed that the carbon flow is through the oxidative tricarboxylic acid (TCA) cycle whereas the reductive TCA cycle is not operative in H. paucihalophilus . In addition, both threonine and the citramalate pathways contribute to isoleucine biosynthesis, whereas lysine is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. Unexpected, the labeling patterns of glycine from the cells grown on [1- 13 C]pyruvate and [2- 13 C]pyruvate suggest that, unlike all the organisms investigated so far, in which glycine is produced exclusively from the serine hydroxymethyltransferase (SHMT) pathway, glycine biosynthesis in H. paucihalophilus involves different pathways including SHMT, threonine aldolase (TA) and the reverse reaction of glycine cleavage system (GCS), demonstrating for the first time that other pathways instead of SHMT can also make a significant contribution to the cellular glycine pool. Transcriptional analysis confirmed that both TA and GCS genes were transcribed in H. paucihalophilus , and the transcriptional level is independent of salt concentrations in the culture media. This study expands our understanding of amino acid biosynthesis and provides valuable insights into the metabolism of halophilic archaea. [ABSTRACT FROM AUTHOR]

Highlights: [•] Tet1 was required for NIT3T3 proliferation. [•] Tet1 depletion inhibited G1-S entry. [•] Cyclin D1 accumulation and Rb phosphorylation was blocked by Tet1 knockdown. [ABSTRACT FROM AUTHOR]