Metformin attenuates post-epidural fibrosis by inhibiting the TGF-β1/Smad3 and HMGB1/TLR4 signaling pathways

Excessive post-epidural fibrosis is a common cause of recurrent back pain after spinal surgery. Though various treatment methods have been conducted, the safe and effective drug for alleviating post-epidural fibrosis remains largely unknown. Metformin, a medicine used in the treatment of type 2 diabetes, has been noted to relieve fibrosis in various organs. In the present study, we aimed to explore the roles and mechanisms of metformin in scar formation in a mouse model of laminectomy. Post-epidural fibrosis developed in a mouse model of laminectomy by spinous process and the T12-L2 vertebral plate with a rongeur. With the administration of metformin, post-epidural fibrosis was reduced, accompanied with decreased collagen and fibronectin in the scar tissues. Mechanistically, metformin decreased fibronectin and collagen deposition in fibroblast cells, and this effect was dependent on the HMGB1/TLR4 and TGF-β1/Smad3 signalling pathways. In addition, metformin influenced the metabolomics of the fibroblast cells. Taken together, our study suggests that metformin may be a potential option to mitigate epidural fibrosis after laminectomy.     

Gα<Subscript>16</Subscript> interacts with tetratricopeptide repeat 1 (TPR1) through its β3 region to activate Ras independently of phospholipase Cβ signaling

Background  

G protein-coupled receptors constitute the largest family of cell surface receptors in the mammalian genome. As the core of the G protein signal transduction machinery, the Gα subunits are required to interact with multiple partners. The GTP-bound active state of many Gα subunits can bind a multitude of effectors and regulatory proteins. Yet it remains unclear if the different proteins utilize distinct or common structural motifs on the Gα subunit for binding. Using Gα₁₆ as a model, we asked if its recently discovered adaptor protein tetratricopeptide repeat 1 (TPR1) binds to the same region as its canonical effector, phospholipase Cβ (PLCβ).     

Lactoferricin mediates anti‐inflammatory and anti‐catabolic effects via inhibition of IL‐1 and LPS activity in the intervertebral disc

The catabolic cytokine interleukin‐1 (IL‐1) and endotoxin lipopolysaccharide (LPS) are well‐known inflammatory mediators involved in degenerative disc disease, and inhibitors of IL‐1 and LPS may potentially be used to slow or prevent disc degeneration in vivo. Here, we elucidate the striking anti‐catabolic and anti‐inflammatory effects of bovine lactoferricin (LfcinB) in the intervertebral disc (IVD) via antagonism of both IL‐1 and LPS‐mediated catabolic activity using in vitro and ex vivo analyses. Specifically, we demonstrate the biological counteraction of LfcinB against IL‐1 and LPS‐mediated proteoglycan (PG) depletion, matrix‐degrading enzyme production, and enzyme activity in long‐term (alginate beads) and short‐term (monolayer) culture models using bovine and human nucleus pulposus (NP) cells. LfcinB significantly attenuates the IL‐1 and LPS‐mediated suppression of PG production and synthesis, and thus restores PG accumulation and pericellular matrix formation. Simultaneously, LfcinB antagonizes catabolic factor mediated induction of multiple cartilage‐degrading enzymes, including MMP‐1, MMP‐3, MMP‐13, ADAMTS‐4, and ADAMTS‐5, in bovine NP cells at both mRNA and protein levels. LfcinB also suppresses the catabolic factor‐induced stimulation of oxidative and inflammatory factors such as iNOS, IL‐6, and toll‐like receptor‐2 (TLR‐2) and TLR‐4. Finally, the ability of LfcinB to antagonize IL‐1 and LPS‐mediated suppression of PG is upheld in an en bloc intradiscal microinjection model followed by ex vivo organ culture using both mouse and rabbit IVD tissue, suggesting a potential therapeutic benefit of LfcinB on degenerative disc disease in the future. J. Cell. Physiol. 228: 1884–1896, 2013. © 2013 Wiley Periodicals, Inc.     

A first AFLP-Based Genetic Linkage Map for Brine Shrimp Artemia franciscana and Its Application in Mapping the Sex Locus

We report on the construction of sex-specific linkage maps, the identification of sex-linked markers and the genome size estimation for the brine shrimp Artemia franciscana. Overall, from the analysis of 433 AFLP markers segregating in a 112 full-sib family we identified 21 male and 22 female linkage groups (2n = 42), covering 1,041 and 1,313 cM respectively. Fifteen putatively homologous linkage groups, including the sex linkage groups, were identified between the female and male linkage map. Eight sex-linked AFLP marker alleles were inherited from the female parent, supporting the hypothesis of a WZ–ZZ sex-determining system. The haploid Artemia genome size was estimated to 0.93 Gb by flow cytometry. The produced Artemia linkage maps provide the basis for further fine mapping and exploring of the sex-determining region and are a possible marker resource for mapping genomic loci underlying phenotypic differences among Artemia species.     

An enzymatic treatment of soil-bound prions effectively inhibits replication

Chronic wasting disease (CWD) and scrapie can be transmitted through indirect environmental routes, possibly via soil, and a practical decontamination strategy for prion-contaminated soil is currently unavailable. In the laboratory, an enzymatic treatment under environmentally relevant conditions (22°C, pH 7.4) can degrade soil-bound PrPSc below the limits of Western blot detection. We developed and used a quantitative serial protein misfolding cyclic amplification (PMCA) protocol to characterize the amplification efficiency of treated soil samples relative to controls of known infectious titer. Our results suggest large (10(4)- to >10(6)-fold) decreases in soil-bound prion infectivity following enzyme treatment, demonstrating that a mild enzymatic treatment could effectively reduce the risk of prion disease transmission via soil or other environmental surfaces.     

Evaluating how hunters see and react to telemetry collars on white-tailed deer

Fates of individuals outfitted with radiotransmitters commonly are used for estimating survival rates in populations of large animals that are hunted. Despite precautions, this practice may be subject to complex biases associated with hunter reaction to presence of radiotransmitters. To assess this potential bias we conducted an experiment using artificial deer (i.e., decoys) to measure hunters' abilities to see deer and determine if deer seen were wearing radiocollars. We used logistic regression to quantify probabilities that seeing deer and subsequently seeing radiocollars might be influenced by distance, percent visual obstruction, body orientation, hunter experience, and antler characteristics of deer. Additionally, we evaluated how experience and antler characteristics of deer might influence a hunter's decision to harvest a radiocollared deer. We found that 25.8% of the potentially observable collared deer (n = 663) were subsequently observed by hunters. Odds of observing deer and radiocollars increased 95% and 230%, respectively, for each additional log(yr) of hunting experience. Willingness to harvest radiocollared deer increased 89% for each additional log(yr) of hunting experience and 144% for large-antlered deer relative to antlerless deer. When hunting is an important source of mortality, analysts need to understand how potential biases associated with observing deer are associated with hunters' reactions to and subsequent decisions to harvest radiocollared animals. Our study suggested that presence of radiocollars may influence a deer's potential risk of being harvested and in turn bias telemetry-based estimates of survival, given that hunting mortality is the largest component of total mortality in hunted deer populations. Collar-based telemetry is used nearly universally by wildlife managers and researchers throughout North America and elsewhere to estimate and monitor the survival of big game populations that are managed through hunting. Our findings demonstrate that these estimates are likely subject to complex and systematic biases that managers should consider when evaluating future population-level effects of managed hunting. © 2011 The Wildlife Society     

Monitoring demographics of a commercially exploited population of shovelnose sturgeon in the Wabash River,Illinois/Indiana,USA

Shovelnose sturgeon (Scaphirhynchus platorynchus, Rafinesque, 1820) in the Wabash River, Illinois/Indiana, USA, provide an important recreational sport and commercial caviar fishery. In fact, it is one of the last commercially viable populations for sturgeon roe harvest. Due to increased demand in the caviar trade and endangered species legislation that protect shovelnose sturgeon in only a portion of their range, efforts of the roe harvest market may continue to divert toward unprotected populations like the shovelnose sturgeon in the Wabash River. Previous studies have shown that increased harvest pressure in this species can affect the age‐at‐maturation and result in recruitment overfishing. Therefore, it is important to closely and continuously monitor commercially exploited populations. Over the past decade (2007–2016), 13,170 shovelnose sturgeon were sampled with boat electroshocking, hoop nets, drift nets, trotlines, and benthic electrified trawls. Captured fish ranged from 61 to 910 mm fork length (FL; mean = 668 mm), with very few fish less than 550 mm FL. Although fish were found to be in a healthy condition (mean relative weight = 87), there was a decrease in the mean condition over time. In addition, we saw declines in mean FL, weight of roe‐per‐fish, and size‐at‐maturity for female fish directly impacted by harvest. The decline of these population parameters, coupled with an increase in total annual mortality and a truncated age frequency distribution, suggest that harvest is negatively impacting the demographics and recruitment of shovelnose sturgeon in the Wabash River. Considering the downward trajectory of population dynamics and high estimates of mortality, their resiliency to continued harvest and environmental changes will be limited.     

Frankenswine,or bringing home the bacon: How close are we to clinical trials in xenotransplantation?

Xenotransplantation—specifically from pig into human—could resolve the critical shortage of organs, tissues and cells for clinical transplantation. Genetic engineering techniques in pigs are relatively well-developed and to date have largely been aimed at producing pigs that either (1) express high levels of one or more human complement-regulatory protein(s), such as decay-accelerating factor or membrane cofactor protein, or (2) have deletion of the gene responsible for the expression of the oligosaccharide, Galα1,3Gal (Gal), the major target for human anti-pig antibodies, or (3) have both manipulations. Currently the transplantation of pig organs in adequately-immunosuppressed baboons results in graft function for periods of 2–6 months (auxiliary hearts) and 2–3 months (life-supporting kidneys). Pig islets have maintained normoglycemia in diabetic monkeys for >6 months. The remaining immunologic barriers to successful xenotransplantation are discussed, and brief reviews made of (1) the potential risk of the transmission of an infectious microorganism from pig to patient and possibly to the public at large, (2) the potential physiologic incompatibilities between a pig organ and its human counterpart, (3) the major ethical considerations of clinical xenotransplantation, and (4) the possible alternatives that compete with xenotransplantation in the field of organ or cell replacement, such as mechanical devices, tissue engineering, stem cell biology and organogenesis. Finally, the proximity of clinical trials is discussed. Islet xenotransplantation is already at the stage where clinical trials are actively being considered, but the transplantation of pig organs will probably require further genetic modifications to be made to the organ-source pigs to protect their tissues from the coagulation/anticoagulation dysfunction that plays a significant role in pig graft failure after transplantation in primates.Key words: islets, pancreatic, genetic engineering, organogenesis, pig, xenotransplantation     

Galloylated catechins and stilbene diglucosides in Vitis vinifera cell suspension cultures

Suspension cultures of Vitis vinifera were found to produce catechins and stilbenes. When cells were grown in a medium inducing polyphenol synthesis, (−)-epicatechin-3-O-gallate, dimeric procyanidin B-2 3′-O-gallate and two resveratrol diglucosides were isolated, together with a new natural compound that was identified as cis-resveratrol-3,4′-O-β-diglucoside by spectroscopical methods.