60 research outputs found
Off-Target Effects of Psychoactive Drugs Revealed by Genome-Wide Assays in Yeast
To better understand off-target effects of widely prescribed psychoactive drugs, we performed a comprehensive series of chemogenomic screens using the budding yeast Saccharomyces cerevisiae as a model system. Because the known human targets of these drugs do not exist in yeast, we could employ the yeast gene deletion collections and parallel fitness profiling to explore potential off-target effects in a genome-wide manner. Among 214 tested, documented psychoactive drugs, we identified 81 compounds that inhibited wild-type yeast growth and were thus selected for genome-wide fitness profiling. Many of these drugs had a propensity to affect multiple cellular functions. The sensitivity profiles of half of the analyzed drugs were enriched for core cellular processes such as secretion, protein folding, RNA processing, and chromatin structure. Interestingly, fluoxetine (Prozac) interfered with establishment of cell polarity, cyproheptadine (Periactin) targeted essential genes with chromatin-remodeling roles, while paroxetine (Paxil) interfered with essential RNA metabolism genes, suggesting potential secondary drug targets. We also found that the more recently developed atypical antipsychotic clozapine (Clozaril) had no fewer off-target effects in yeast than the typical antipsychotics haloperidol (Haldol) and pimozide (Orap). Our results suggest that model organism pharmacogenetic studies provide a rational foundation for understanding the off-target effects of clinically important psychoactive agents and suggest a rational means both for devising compound derivatives with fewer side effects and for tailoring drug treatment to individual patient genotypes
Inflammatory responses to acute exercise during pulmonary rehabilitation in patients with COPD
Objective
Pulmonary rehabilitation is a cornerstone treatment in the management of chronic obstructive pulmonary disease (COPD). Acute bouts of exercise can lead to short bursts of inflammation in healthy individuals. However, it is unclear how COPD patients respond to acute bouts of exercise. This study assessed inflammatory responses to exercise in COPD patients at the start (phase 1) and end (phase 2) of pulmonary rehabilitation.
Methods
Blood samples were collected before and after an acute exercise bout at the start (phase 1, n = 40) and end (phase 2, n = 27) of pulmonary rehabilitation. The primary outcome was change in fibrinogen concentrations. Secondary outcomes were changes in CRP concentrations, total/differential leukocyte counts, markers of neutrophil activation (CD11b, CD62L and CD66b), and neutrophil subsets (mature, suppressive, immature, progenitor).
Results
Acute exercise (phase 1) did not induce significant changes in fibrinogen (p = 0.242) or CRP (p = 0.476). Total leukocyte count [mean difference (MD), 0.5 ± 1.1 (109 L−1); p = 0.004], neutrophil count [MD, 0.4 ± 0.8 (109 L−1); p < 0.001], and immature neutrophils (MD, 0.6 ± 0.8%; p < 0.001) increased post-exercise. Neutrophil activation markers, CD11b (p = 0.470), CD66b (p = 0.334), and CD62L (p = 0.352) were not significantly altered post-exercise. In comparison to the start of pulmonary rehabilitation (phase 2), acute exercise at the end of pulmonary rehabilitation led to a greater fibrinogen response (MD, 84 mg/dL (95% CI − 14, 182); p = 0.045).
Conclusion
An acute bout of exercise does not appear to induce significant alterations in the concentrations of inflammatory mediators but can increase white blood cell subsets post-exercise. A greater fibrinogen response to acute exercise is seen at the end of pulmonary rehabilitation when compared to the start. Further research is required to understand the clinical context of these acute inflammatory responses to exercise
miR-143 Overexpression Impairs Growth of Human Colon Carcinoma Xenografts in Mice with Induction of Apoptosis and Inhibition of Proliferation
BACKGROUND: MicroRNAs (miRNAs) are aberrantly expressed in human cancer and involved in the (dys)regulation of cell survival, proliferation, differentiation and death. Specifically, miRNA-143 (miR-143) is down-regulated in human colon cancer. In the present study, we evaluated the role of miR-143 overexpression on the growth of human colon carcinoma cells xenografted in nude mice (immunodeficient mouse strain: N: NIH(s) II-nu/nu). METHODOLOGY/PRINCIPAL FINDINGS: HCT116 cells with stable miR-143 overexpression (Over-143) and control (Empty) cells were subcutaneously injected into the flanks of nude mice, and tumor growth was evaluated over time. Tumors arose ∼ 14 days after tumor cell implantation, and the experiment was ended at 40 days after implantation. miR-143 was confirmed to be significantly overexpressed in Over-143 versus Empty xenografts, by TaqMan® Real-time PCR (p<0.05). Importantly, Over-143 xenografts displayed slower tumor growth compared to Empty xenografts from 23 until 40 days in vivo (p<0.05), with final volumes of 928±338 and 2512±387 mm(3), respectively. Evaluation of apoptotic proteins showed that Over-143 versus Empty xenografts displayed reduced Bcl-2 levels, and increased caspase-3 activation and PARP cleavage (p<0.05). In addition, the incidence of apoptotic tumor cells, assessed by TUNEL, was increased in Over-143 versus Empty xenografts (p<0.01). Finally, Over-143 versus Empty xenografts displayed significantly reduced NF-κB activation and ERK5 levels and activation (p<0.05), as well as reduced proliferative index, evaluated by Ki-67 immunohistochemistry (p<0.01). CONCLUSIONS: Our results suggest that reduced tumor volume in Over-143 versus Empty xenografts may result from increased apoptosis and decreased proliferation induced by miR-143. This reinforces the relevance of miR-143 in colon cancer, indicating an important role in the control of in vivo tumor progression, and suggesting that miR-143 may constitute a putative novel therapeutic tool for colon cancer treatment that warrants further investigation
Distinct Type of Transmission Barrier Revealed by Study of Multiple Prion Determinants of Rnq1
Prions are self-propagating protein conformations. Transmission of the prion state between non-identical proteins, e.g. between homologous proteins from different species, is frequently inefficient. Transmission barriers are attributed to sequence differences in prion proteins, but their underlying mechanisms are not clear. Here we use a yeast Rnq1/[PIN+]-based experimental system to explore the nature of transmission barriers. [PIN+], the prion form of Rnq1, is common in wild and laboratory yeast strains, where it facilitates the appearance of other prions. Rnq1's prion domain carries four discrete QN-rich regions. We start by showing that Rnq1 encompasses multiple prion determinants that can independently drive amyloid formation in vitro and transmit the [PIN+] prion state in vivo. Subsequent analysis of [PIN+] transmission between Rnq1 fragments with different sets of prion determinants established that (i) one common QN-rich region is required and usually sufficient for the transmission; (ii) despite identical sequences of the common QNs, such transmissions are impeded by barriers of different strength. Existence of transmission barriers in the absence of amino acid mismatches in transmitting regions indicates that in complex prion domains multiple prion determinants act cooperatively to attain the final prion conformation, and reveals transmission barriers determined by this cooperative fold
A review on herbal antiasthmatics
In traditional systems of medicine, many plants have been documented to be useful for the treatment of various respiratory disorders including asthma. In the last two decades the use of medicinal plants and natural products has been increased dramatically all over the world. Current synthetic drugs used in pharmacotherapy of asthma are unable to act at all the stages and targets of asthma. However some herbal alternatives employed in asthma are proven to provide symptomatic relief and assist in the inhibition of disease progression also. The herbs have shown interesting results in various target specific biological activities such as bronchodilation, mast cell stabilization, anti-anaphylactic, anti-inflammatory, anti-spasmodic, anti-allergic, immunomodulatory and inhibition of mediators such as leukotrienes, lipoxygenase, cyclooxygenase, platelet activating, phosphodiesterase and cytokine, in the treatment of asthma. This paper is an attempt to classify these pharmacological and clinical findings based on their possible mechanism of action reported. It also signifies the need for development of polyherbal formulations containing various herbs acting at particular sites of the pathophysiological cascade of asthma for prophylaxis as well as for the treatment of asthma
Proteins on the catwalk: modelling the structural domains of the CCN family of proteins
The CCN family of proteins (CCN1, CCN2, CCN3, CCN4, CCN5 and CCN6) are multifunctional mosaic proteins that play keys roles in crucial areas of physiology such as angiogenesis, skeletal development tumourigenesis, cell proliferation, adhesion and survival. This expansive repertoire of functions comes through a modular structure of 4 discrete domains that act both independently and in concert. How these interactions with ligands and with neighbouring domains lead to the biological effects is still to be explored but the molecular structure of the domains is likely to play an important role in this. In this review we have highlighted some of the key features of the individual domains of CCN family of proteins based on their biological effects using a homology modelling approach
Stroke in women — from evidence to inequalities
Stroke is the second largest cause of disability-adjusted life-years lost worldwide. The prevalence of stroke in women is predicted to rise rapidly, owing to the increasing average age of the global female population. Vascular risk factors differ between women and men in terms of prevalence, and evidence increasingly supports the clinical importance of sex differences in stroke. The influence of some risk factors for stroke — including diabetes mellitus and atrial fibrillation — are stronger in women, and hypertensive disorders of pregnancy also affect the risk of stroke decades after pregnancy. However, in an era of evidence-based medicine, women are notably under-represented in clinical trials — despite governmental actions highlighting the need to include both men and women in clinical trials — resulting in a reduced generalizability of study results to women. The aim of this Review is to highlight new insights into specificities of stroke in women, to plan future research priorities, and to influence public health policies to decrease the worldwide burden of stroke in women
Protective Effect of Ethanolic Extract of Saussurea Lappa on Paracetamol Induced Toxicity in Female Rabbits
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