Continuous exposure of nicotine and cotinine retards human primary pterygium cell proliferation and migration

Pterygium is a triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. Our previous meta-analysis found that cigarette smoking is associated with a reduced risk of pterygium. Yet, the biological effect of cigarette smoke components on pterygium has not been studied. Here we reported the proliferation and migration properties of human primary pterygium cells with continuous exposure to nicotine and cotinine. Human primary pterygium cells predominantly expressed the α5, β1, and γ subunits of the nicotinic acetylcholine receptor. Continuous exposure to the mixture of 0.15 μM nicotine and 2 μM cotinine retarded pterygium cell proliferation by 16.04% (P = 0.009) and hindered their migration by 11.93% ( P = 0.039), without affecting cell apoptosis. SNAIL and α-smooth muscle actin protein expression was significantly downregulated in pterygium cells treated with 0.15 μM nicotine-2 μM cotinine mixture by 1.33- ( P = 0.036) and 1.31-fold ( P = 0.001), respectively. Besides, the 0.15 μM nicotine-2 μM cotinine mixture also reduced matrix metalloproteinase (MMP)-1 and MMP-9 expressions in pterygium cells by 1.56- ( P = 0.043) and 1.27-fold ( P = 0.012), respectively. In summary, this study revealed that continuous exposure of nicotine and cotinine inhibited human primary pterygium cell proliferation and migration in vitro by reducing epithelial-to-mesenchymal transition and MMP protein expression, partially explaining the lower incidence of pterygium in cigarette smokers.     

Inhibition of lncRNA MEG3 protects renal tubular from hypoxia-induced kidney injury in acute renal allografts by regulating miR-181b/TNF-α signaling pathway

Early damage to transplanted organs initiates excess inflammation that deteriorates existing injury, which is a leading cause of graft loss. Long noncoding RNAs (lncRNAs) are recently thought to play a significant role in cellular homeostasis during pathological process of kidney diseases. The aim of this study was to assess the function and mechanism of lncRNA, maternally expressed gene 3 (MEG3), on early renal allografts pathogenesis. Real-time polymerase chain reaction (RT-PCR) analysis found that the levels of MEG3 and miR-181b-5p were increased and decreased respectively in grafted kidney. The Western blot assay showed that TNF-alpha was upregulated in the kidney and in HK-2 cells. Administering MEG3-specific small interfering RNA (siRNA) in mice silenced MEG3 expression and protected kidney renal allograft from injury. Bioinformatical analysis and luciferase assay indicated that MEG3 is a target of miR-181b-5p. MEG3 inhibition and overexpression promoted and suppressed miR-181b-5p levels respectively. In addition, Western blot and immunohistochemical staining suggested that decreased TNF-alpha expression was observed in the kidney. In contrary to MEG3, miR181b overexpression attenuated hypoxia-induced HK-2 cell apoptosis, as well as suppressed hypoxia-induced TNF-alpha upregulation. In luciferase reporter assay, we confirmed that miR-181b directly bound to the 3′-untranslated region (3′-UTR) of TNF-alpha, thereby negatively regulating the TNF-alpha expression. Our data suggested that MEG3 functions as a competing endogenous RNA for miR-181b to regulate the TNF-alpha expression in hypoxia-induced kidney injury in acute renal allografts.     

YAP1 regulates PPARG and RXR alpha expression to affect the proliferation and differentiation of ovine preadipocyte

Adipose tissue development is regulated by a serial of developmental signaling pathways. The Hippo pathway is a novel signaling cascade closely associated with adipogenesis. While most of Hippo pathway components had been verified that have a vital role in preadipocytes proliferation and differentiation, little is known about the function of Yes-associated protein 1 (YAP1) in mammalian adipose tissue development. Therefore, we investigated the role of YAP1 in ovine adipose tissue development by in vitro and in vivo experiments. We observed that the adipocyte size in subcutaneous adipose tissue increased with development. YAP1 expression increased during adipose tissue development, while decreased during the differentiation of ovine preadipocytes in vitro. YAP1 knockdown notably promoted lipid accumulation and suppressed ovine preadipocyte proliferation. In addition, we observed that YAP1 deficiency significantly upregulated peroxisome proliferator-activated receptor gamma (PPARG) and retinoid X receptor alpha (RXR alpha) expression. By contrast, overexpression of YAP1 led to the suppression of preadipocyte differentiation, lipid droplets formation, and PPARG expression. In brief, our findings demonstrated that YAP1 regulates the proliferation and differentiation of ovine preadipocyte via altering PPARG and RXR alpha expression.     

Three Tibetan grassland plant species tend to partition niches with limited plasticity in nitrogen use

Plant and Soil - Niche complementarity theory explains how species coexist by using different resources. Two pathways to partition resource have been demonstrated: classical niche differentiation...     

Exosomes from miR‐20b‐3p‐overexpressing stromal cells ameliorate calcium oxalate deposition in rat kidney

Hyperoxaluria‐induced calcium oxalate (CaOx) deposition is the key factor in kidney stone formation, for which adipose‐derived stromal cells (ADSCs) have been used as a therapeutic treatment. Studies revealed that miR‐20b‐3p is down‐regulated in hypercalciuric stone‐forming rat kidney. To investigate whether ADSC‐derived miR‐20b‐3p‐enriched exosomes protect against kidney stones, an ethylene glycol (EG)‐induced hyperoxaluria rat model and an in vitro model of oxalate‐induced NRK‐52E cells were established to explore the protective mechanism of miR‐20b‐3p. The results showed that miR‐20b‐3p levels were decreased following hyperoxaluria in the urine of patients and in kidney tissues from animal models. Furthermore, treatment with miR‐20b‐3p‐enriched exosomes from ADSCs protected EG‐induced hyperoxaluria rats, and cell experiments confirmed that co‐culture with miR‐20b‐3p‐enriched exosomes alleviated oxalate‐induced cell autophagy and the inflammatory response by inhibiting ATG7 and TLR4. In conclusion, ADSC‐derived miR‐20b‐3p‐enriched exosomes protected against kidney stones by suppressing autophagy and inflammatory responses.     

Ras-related proteins (Rab) are key proteins related to male fertility following a unique activation mechanism

Ras-related protein Rab (Rab) proteins, member of Ras superfamily of monomeric G proteins, are well known key regulators of intracellular vesicular transport. Recently, it has been reported that Rab 2A and 3A are related to acrosomal exocytosis in spermatozoa and Rab 2A can be used to fertility-related biomarker in male. However, the role and mechanism of Rab proteins in spermatozoa has not been fully understood yet. Therefore, the study to analyze the expression and location of various Rab proteins in spermatozoa is required to understand the role and mechanism of Rab proteins in spermatozoa. In present study, to analyze the expression level and location of various Rab proteins (Rab 2A, Rab3A, Rab4, Rab5, Rab8A, Rab9, Rab11, Rab14, Rab25, Rab27A, and Rab34) and Rab protein regulators (RabGAP, RabGDI, RabGEF) in spermatozoa following capacitation, immunofluorescence and western blot analysis were performed. All of 11 Rab proteins were expressed in acrosomal region and tail of spermatozoa. Furthermore, all Rab proteins and Rab protein regulators, except RabGAP, have decreased expression patterns after capacitation. Taken together, Rab proteins were located in sperm head and tail. In addition, expression patterns of Rab proteins in spermatozoa were altered following capacitation. Therefore, our results suggested that Rab proteins may be key proteins related with capacitation as well as playing important role with uniquely activation pathway for male fertility.     

Triptolide suppresses pancreatic cancer cell proliferation by inhibiting hedgehog signaling pathway activity

正Dear Editor,Pancreatic cancer (PCa) is a high-grade gastrointestinal malignancy more commonly occurring in elderly populations with lower than 5% overall 5-year survival rate (Hidalgo, 2010). PCa responds poorly to most chemotherapeutic agents, and therefore it is imperative to develop novel therapeutic agents that have anti-cancer activities against PCa.     

Optimization and performance validation for the fully automatic blood type analysis system

To evaluate and validate the application of fully automatic blood type analysis system parameters under actual lab conditions. All key system parameters were optimized and validated accordingly. The optimized parameters were centrifugal speed at 550 rpm; centrifugal time 20 min; resuspension speed 1,200 rpm; resuspension time: 45 s; incubation temperature 25℃ ; incubation time 400 s; incubation rate: 0 rpm. The sampled red blood cell concentration was 3%. The ratio of plasma to red blood cells reagent was 60 μL:30 μL; the ratio of antibody (reagent) to sampled diluted red blood cell was 30 μL:30 μL. After applying our key parameters for optimization and validation, the automatic blood type detection system's performance was found to meet the relevant requirements, effectively improving the accuracy and reliability of the detection system.