Structural and functional characterization of simvastatin-induced myotoxicity in different skeletal muscles

Feasibility of Raman spectroscopic identification of gall bladder cancer using extracellular vesicles extracted from bile

Extracellular vesicles (EVs), which are heterogeneous membrane-based vesicles with bilayer cell membrane structures, could be versatile biomarkers for the identification of diverse diseases including cancers. With this potential, this study has attempted the Raman spectroscopic identification of gall bladder (GB) cancer by directly measuring the EV solution extracted from human bile without further sample drying. For this purpose, bile samples were obtained from four normal individuals and 21 GB polyp, eight hepatocellular carcinoma (HCC), and five GB cancer patients, and EVs were extracted from each of the bile samples. The Raman peak shapes of the EVs extracted from the GB cancer samples, especially the relative intensities of peaks in the 1560-1340 cm-1 range, were dissimilar to those of the samples from the normal, GB polyp, and HCC groups. The intensity ratios of peaks at 1537 and 1453 cm-1 and at 1395 and 1359 cm-1 of the GB cancer samples were lower and higher, respectively, than those of the samples of the remaining three groups. The differences of peak intensity ratios were statistically significant based on the Mann-Whitney U test. DNA/RNA bases, amino acids, and bile salts contributed to the spectra of EVs, and their relative abundances seemed to vary according to the occurrence of GB cancer. The varied metabolite compositions and/or structures of EVs were successfully demonstrated by the dissimilar peak intensity ratios in the Raman spectra, thereby enabling the discrimination of GB cancer.

The effects of simvastatin and fenofibrate on malondialdehyde and reduced glutathione concentrations in the plasma, liver, and brain of normolipidaemic and hyperlipidaemic rats

The objective of study was to investigate the effects of different doses of simvastatin and fenofibrate on malondialdehyde (MDA) and reduced glutathione (GSH) in the plasma, liver, and brain tissue of male normolipidaemic and hyperlipidaemic rats. Normolipidaemic (Wistar) rats were receiving 10 or 50 mg/kg a day of simvastatin or 30 or 50 mg/kg a day of fenofibrate. Hyperlipidaemic (Zucker) rats were receiving 50 mg/kg/day of simvastatin or 30 mg/kg/day of fenofibrate. Control normolipidaemic and hyperlipidaemic rats were receiving saline. Simvastatin, fenofibrate, and saline were administered by gavage for three weeks. In normolipidaemic rats simvastatin and fenofibrate showed similar and dose-independent effects on plasma and brain MDA and GSH concentrations. Generally, plasma and brain MDA decreased, while brain GSH concentration increased. In hyperlipidaemic rats simvastatin did not affect plasma and brain MDA and GSH concentrations but significantly decreased liver GSH. Fenofibrate decreased plasma and liver MDA but increased brain MDA. In both rat strains fenofibrate significantly decreased liver GSH concentrations, most likely because fenofibrate metabolites bind to GSH. Our findings suggest that simvastatin acts as an antioxidant only in normolipidaemic rats, whereas fenofibrate acts as an antioxidant in both rat strains.

Direct Bactericidal Comparison of Metal Nanoparticles and Their Salts against S. aureus Culture by TEM and FT-IR Spectroscopy

We report the bactericidal effect of Ag and Cu NPs with different concentrations on methicillin-resistant S. aureus strain in comparison to the effect of AgNO₃ and CuCl₂ solutions, characterized by microbiological tests, TEM and Fourier-transform infrared spectroscopy. NPs were produced by nanosecond laser ablation in distilled water and characterized by scanning electron microscopy, UV-vis, energy dispersive X-ray, FT-IR spectroscopy, as well as X-ray diffraction, dynamic light scattering size and zeta-potential measurements. Microbiological tests showed antibacterial activity of NPs and metal ion-containing salts. Comparative FT-IR spectroscopy of bacteria, treated with metal NPs and salts, showed the broadening of amide I and II bands, a CH₂-related peak and its frequency decrease, indicating the increase of membrane fluidity. The main mechanisms of the antibacterial effect were proposed: Ag and Cu NPs release ions and ROS, which result in lipid peroxidation; AgNO₃ forms precipitates on the cell surface, which lead to the mechanical rupture of the membrane and subsequent possible penetration of the precipitates in the emerged damaged spots, complete destruction of the membrane and bacterial death; Cu ions from the CuCl₂ solution cause damage to phosphorus- and sulfur-containing biomolecules, which leads to disruption of intracellular biochemical processes. The theories were confirmed by FT-IR spectroscopy and TEM.

Dimethyl phthalate destroys the cell membrane structural integrity of Pseudomonas fluorescens

A Gram-negative bacteria (Pseudomonas fluorescens) was exposed to different concentrations (0, 20, and 40 mg/L) of dimethyl phthalate (DMP) for 8 h, and then Fourier transform infrared spectroscopy (FTIR) analysis, lipopolysaccharide content detection, analysis of fatty acids, calcein release test, proteomics, non-targeted metabolomics, and enzyme activity assays were used to evaluate the toxicological effect of DMP on P. fluorescens. The results showed that DMP exposure caused an increase in the unsaturated fatty acid/saturated fatty acid (UFA/SFA) ratio and in the release of lipopolysaccharides (LPSs) from the cell outer membrane (OM) of P. fluorescens. Moreover, DMP regulated the abundances of phosphatidyl ethanolamine (PE) and phosphatidyl glycerol (PG) of P. fluorescens and induced dye leakage from an artificial membrane. Additionally, excessive reactive oxygen species (ROS), malondialdehyde (MDA), and changes in antioxidant enzymes (i.e., catalase [CAT] and superoxide dismutase [SOD]) activities, as well as the inhibition of Ca²⁺-Mg²⁺-ATPase and Na⁺/K⁺-ATPase activities in P. fluorescens, which were induced by the DMP. In summary, DMP could disrupt the lipid asymmetry of the outer membrane, increase the fluidity of the cell membrane, and destroy the integrity of the cell membrane of P. fluorescens through lipid peroxidation, oxidative stress, and ion imbalance.

Evaluation of the hydrogen-rich water alleviation potential on mercury toxicity in earthworms using ATR-FTIR and LC-ESI-MS/MS spectroscopy

The toxic effects of mercury in earthworms and the potential alleviation effect of hydrogen-rich water (HRW) using ATR-FTIR and LC-MS analysis methods were investigated. Different concentrations of mercury chloride (H1: 5 µg/mL, H2: 10 µg/mL, H3: 20 µg/mL, H4: 40 µg/mL, and C1: control) and mercury chloride prepared in hydrogen-rich water (H5: 5 µg/mL, H6: 10 µg/mL, H7: 20 µg/mL, H8: 40 µg/mL, and C2: control) were injected into earthworms. The changes and reductions in some bands representing proteins, lipids, and polysaccharides (3280 cm^-1, 2922 cm^-1, 2855 cm^-1, 1170 cm^-1, and 1047 cm^-1) showed that protective effects could occur in groups prepared with hydrogen-rich water. In the FTIR results, it was found that these bands in the H3 group were more affected and decreased by the influence of mercury on earthworms than the H7 group prepared with hydrogen. LC-MS analysis showed that the changes in some ions of the highest dose groups (H4 and H8) were different, and mercury caused oxidative DNA damage in earthworms. When the high-level application groups of mercury, i.e., H4 and H8 were compared with the controls, the ion exchange ([M + H] + ; m/z 283.1) representing the 8-Oxo-dG level in earthworms was higher in the H4 group than the H8 group. This reveals that HRW exhibited the potential ability to alleviate the toxic effects of mercury; however, a longer period of HRW treatment may be necessary to distinguish an obvious effect. The ATR-FTIR spectroscopy provided a rapid and precise method for monitoring the changes in biological tissues caused by a toxic compound at the molecular level.

Brain DNA damage analysis in pesticide exposed wistar albino rats (Rattus norvegicus): a chemometric approach

Brain the most important organ which controls most of the regulations in the body is composed of neurons and glia. As brain has a high metabolic rate and reduced cell renewal capability, the lipids, proteins and nucleic acids become the major targets of damage. In the present study carbofuran (CF) induced brain DNA damage in male wistar albino rats at sub-lethal doses (Control-A; B-1.0, C-0.5 and D-0.3 mg/kg BW) while the groups B1,C1, D1, B2, C2, D2 and B3, C3, D3 represents the exposure duration 30, 60 and 90 days each respectively. FTIR spectroscopy based chemometric analysis of functional groups in nucleic acids are reported, changes in band area and band frequencies were examined to understand the DNA damage by constructing heat map. Significant changes were observed in the band frequency, band areas, bandwidth and intensity values (p < 0.05, 0.01, 0.001). The principal component analysis was analyzed to study the alterations at the molecular level, which revealed maximum variance of 74% in groups A, B1, C1, D1 and C2 and 13.7% variance in B2, D2, B3, C3 and D3. The present study provides significant details to analyse DNA damage using non-conventional approach and can also be used for detecting DNA damage in several neural diseases and disorders and emphasizes on using FTIR spectral data through chemometric approach to analyse the DNA damage.Communicated by Ramaswamy H. Sarma.

New insight into the negative impact of imidazolium-based ionic liquid [C10mim]Cl on Hela cells: From membrane damage to biochemical alterations

As an alternative to volatile organic solvents, ionic liquids (ILs) are known as "green solvents", and widely used in industrial applications. However, due to their high solubility and stability, ILs have tendency to persist in the water environment, thus having potential negative impacts on the aquatic ecosystem. For assessing the environmental risks of ILs, a fundamental understanding of the toxic effects and mechanisms of ILs is needed. Here we evaluated the cytotoxicity of 1-methyl-3-decylimidazolium chloride ([C₁₀mim]Cl) and elucidated the main toxic mechanism of [C₁₀mim]Cl in human cervical carcinoma (Hela) cells. Microstructural analysis revealed that [C₁₀mim]Cl exposure caused the cell membrane breakage, swollen and vacuolated mitochondria, and spherical cytoskeletal structure. Cytotoxicity assays found that [C₁₀mim]Cl exposure increased ROS production, decreased mitochondrial membrane potential, induced cell apoptosis and cell cycle arrest. These results indicated that [C₁₀mim]Cl could induce damage to cellular membrane structure, affect the integrity of cell ultrastructure, cause the oxidative damage and ultimately lead to the inhibition of cell proliferation. Moreover, alterations of biochemical information including the increased ratios of unsaturated fatty acid and carbonyl groups to lipid, and lipid to protein, and the decreased ratios of Amide I to Amide II, and α-helix to β-sheet were observed in [C₁₀mim]Cl treated cells, suggesting that [C₁₀mim]Cl could affect the structure of membrane lipid alkyl chain and cell membrane fluidity, promote the lipid peroxidation and alter the protein secondary structure. The findings from this work demonstrated that membrane structure is the key target, and membrane damage is involved in [C₁₀mim]Cl induced cytotoxicity.

Geranylgeraniol prevents statin-induced skeletal muscle fatigue without causing adverse effects in cardiac or vascular smooth muscle performance

The administration of geranylgeranyl pyrophosphate (GGPP) (or its precursor, geranylgeraniol [GGOH]) has been shown by several in vitro studies to be capable of abrogating statin-induced myotoxicity. Nonetheless, the potential of GGPP repletion to prevent statin-associated muscle symptoms (SAMS) in vivo is yet to be investigated. Therefore, this study aimed to evaluate the ability of GGOH to prevent SAMS in rodents. Female Wistar rats (12 weeks of age) were randomised to 1 of 4 treatment groups: control, control with GGOH, simvastatin or simvastatin with GGOH. Ex vivo assessment of force production was conducted in skeletal muscles of varying fiber composition. Ex vivo left ventricular performance and blood vessel function was also assessed to determine if the administration of GGOH caused adverse changes in these parameters. Statin administration was associated with reduced force production in fast-twitch glycolytic muscle, but coadministration with GGOH completely abrogated this effect. Additionally, GGOH improved the performance of muscles not adversely affected by simvastatin (ie, those with a greater proportion of slow-twitch oxidative fibers), and increased force production in the control animals. Neither control nor statin-treated rodents given GGOH exhibited adverse changes in cardiac function. Vascular relaxation was also maintained following treatment with GGOH. The findings of this study demonstrate that GGOH can prevent statin-induced skeletal muscle fatigue in rodents without causing adverse changes in cardiovascular function. Further studies to elucidate the exact mechanisms underlying the effects observed in this investigation are warranted.

Assessment of bee venom therapy in animal model of statin-induced myopathy

Background

Statin-induced myopathy is the most common adverse effect of statins. Bee venom provides a potential mean of controlling immune responses and inflammatory reactions; the proposed mechanisms for statin-induced myopathy.

Objective

The present study aimed at clarification of the role of the bee venom in prevention of statin-induced myopathy.

Materials and methods

It was carried out on 30 Sprague-Dawley female rats. Rats were randomly classified into 3 groups: control group, statin group which received statins for 2 weeks, and venom group that was exposed to alternate day actual bee sting concurrent to statins administration for 2 weeks. Quantitative electromyography (QEMG) was performed as well as serum creatine kinase (CK) and cholesterol levels, in addition to in vitro muscle contractility tests.

Results

QEMG and contractility tests showed significant changes in the statin group compared to both control and venom groups. Serum cholesterol level decreased with increase in CK levels in the statin and venom groups compared to controls; however, the CK level was significantly lower in the venom group as compared to the statin group.

Conclusion

Bee venom therapy offers a simple and available means of prophylaxis against the myopathic effects induced by statins in animal model. However, it partly restricts the therapeutic effect of statins.

Insights into the sediment toxicity of personal care products to freshwater oligochaete worms using Fourier transform infrared spectroscopy

Personal care products (PCPs) are ubiquitous in the environment due to their wide use in daily life. However, there are insufficient sediment toxicity data of PCPs under ecologically relevant conditions. Here we used Fourier transform infrared spectroscopy (FTIR) to investigate the sediment toxicity of triclosan (TCS) and galaxolide (HHCB) to two freshwater benthic macroinvertebrates, Limnodrilus hoffmeisteri and Branchiura sowerbyi, in microcosms containing a diverse biological community. Exposure to 8 µg TCS/g and 100 µg HHCB/g dry weight (dw) sediment induced significant biochemical alterations in the L. hoffmeisteri tissue. 8 µg TCS/g primarily affected proteins and nucleic acid while 100 µg HHCB/g mainly affected proteins and lipids of L. hoffmeisteri. However, 0.8 µg TCS/g and 30 µg HHCB/g did not cause significant subcellular toxicity to L. hoffmeisteri. In contrast, exposure of B. sowerbyi to 30 µg HHCB/g led to significant biochemical changes, including proteins, polysaccharides and lipids. Therefore, B. sowerbyi was more sensitive to sediment-associated HHCB than L. hoffmeisteri. Such effects were significantly enhanced when the HHCB concentration increased to 100 µg/g dw where death of B. sowerbyi occurred. These results demonstrate the application of FTIR spectroscopy to sediment toxicity testing of chemicals to benthic invertebrates with biochemical alterations as endpoints that are more sensitive than standard toxic endpoints (e.g., survival and growth).

FTIR-based comparative analysis of glucomannan contents in some tuberous orchids, and effects of pre-processing on glucomannan measurement

BACKGROUND

Glucomannan (GM) is a polysaccharide of the mannan family of compounds found in some plant species. The dried and powdered tubers of some orchid species, collectively known as 'salep powder,' are a commercially important crop for human consumption and are one of the primary sources of GM. GM content is the primary indicator for the yield and quality of salep powder. We hypothesized that it would be more practical and accurate to measure GM content within tuber powder directly, prior to any purification or pre-processing. The GM content of tubers of 14 different orchid species was evaluated and compared using Fourier transform infrared (FTIR) spectroscopy and an enzymatic colorimetric method.

RESULTS

Among the analyzed modes, the sum of the peak areas at 873 and 812 cm^-1 , which represent the CH bending attributed to the β-pyranose form of d-glucose and d-mannose, respectively, gave the only confirmation using colorimetric methods. It was found that the tubers of Himantoglossum caprinum and Serapias vomeracea had the highest GM concentrations among the analyzed species. After conducting different pre-processing steps on Serapias vomeracea tubers, it was found that treating the tubers with milk, or high temperature resulted in an apparent increase in GM concentrations.

CONCLUSION

Himantoglossum caprinum and Serapias vomeracea give the highest yields of GM and should be used for commercial horticulture. GM estimation should be made prior to any pre-processing. FTIR spectroscopy is effective and reliable for directly comparing GM content of different orchid species, without the need for any purification or pre-processing. © 2019 Society of Chemical Industry.

Molecular characterization of acutely and gradually heavy metal acclimated aquatic bacteria by FTIR spectraoscopy

In the environment, bacteria can be exposed to the concentration gradient of toxic heavy metals (gradual) or sudden high concentration of them (acute). In both situations, bacteria get acclimated to toxic heavy metal concentrations. Acclimation causes metabolic and molecular changes in bacteria. In this study, we aimed to understand whether there are differences between molecular profiles of the bacteria (Brevundimonas, Gordonia and Microbacterium) which are under acute or gradual exposure to cadmium or lead by using ATR-FTIR spectroscopy. Our results revealed the differences between the acclimation groups in membrane dynamics including changes in the structure and composition of the membrane lipids and proteins. Furthermore, protein concentrations decreased in acclimated bacterial groups. Also, a remarkable increase in exopolymer production occurred in acclimated groups. Interestingly, bacteria under acute cadmium exposure produced the significantly higher amount of exopolymer than they did under gradual exposure. On the contrary, under lead exposure gradually acclimate strains produced significantly higher amounts of exopolymer than those of acutely acclimated ones. This information can be used in bioremediation studies to obtain bacterial strains producing a higher amount of exopolymer.

Fast skeletal troponin I, but not the slow isoform, is increased in patients under statin therapy: a pilot study

Introduction

Statin therapy is often associated with muscle complaints and increased serum creatine kinase (CK). However, although essential in determining muscle damage, this marker is not specific for skeletal muscle. Recent studies on animal models have shown that slow and fast isoforms of skeletal troponin I (ssTnI and fsTnI, respectively) can be useful markers of skeletal muscle injury. The aim of this study was to evaluate the utility of ssTnI and fsTnI as markers to monitor the statin-induced skeletal muscle damage.

Materials and methods

A total of 51 patients (14 using and 37 not using statins) admitted to the intensive care unit of the University of Ferrara Academic Hospital were included in this observational study. Serum activities of CK, aldolase, alanine aminotransferase and myoglobin were determined by spectrophotometric assays or routine laboratory analysis. Isoforms ssTnI and fsTnI were determined by commercially available ELISAs. The creatine kinase MB isoform (CK-MB) and cardiac troponin I (cTnI) were evaluated as biomarkers of cardiac muscle damage by automatic analysers.

Results

Among the non-specific markers, only CK was significantly higher in statin users (P = 0.027). Isoform fsTnI, but not ssTnI, was specifically increased in those patients using statins (P = 0.009) evidencing the major susceptibility of fast-twitch fibres towards statins. Sub-clinical increase in fsTnI, but not CK, was more frequent in statin users (P = 0.007). Cardiac markers were not significantly altered by statins confirming the selectivity of the effect on skeletal muscle.

Conclusions

Serum fsTnI could be a good marker for monitoring statin-associated muscular damage outperforming traditional markers.

The impact of self-replicating proteins on inflammation, autoimmunity and neurodegeneration-An untraveled path

The central nervous system (CNS) in neurodegenerative diseases is a battlefield in which microglia fight a highly atypical battle. During the inflammatory process microglia themselves become dysfunctional and even with all the available immune arsenal including cytokine or/and antibody production, the battle is eventually lost. A closer look into the picture will reveal the fact that this is mainly due to the atypical characteristics of the infectious agent. The supramolecular assemblies of misfolded proteins carry unique features not encountered in any of the common pathogens. Through misfolding, proteins undergo conformational changes which make them become immunogenic, neurotoxic and highly infective. The immunogenicity appears to be triggered by the exposure of previously hidden hydrophobic portions in proteins which act as damage-associated molecular patters (DAMPs) for the immune system. The neurotoxicity and infectivity are promoted by the small oligomeric forms of misfolded proteins/peptides. Oligomers adopt conformations such as tubular-like, beta-barrel-like, etc., that penetrate cell membranes through their hydrophobic surfaces, thus destabilizing ionic homeostasis. At the same time, oligomers act as a seed for protein misfolding through a prion/prion-like mechanism. Here, we propose the hypothesis that oligomers have catalytic surfaces and exercise their capacity to infect native proteins through specific characteristics such as hydrophobic, electrostatic and π-π stacking interactions as well as the specific surface area (SSA), surface curvature and surface chemistry of their nanoscale supramolecular assemblies. All these are the key elements for prion/prion-like mechanism of self-replication and disease spreading within the CNS. Thus, understanding the mechanism of prion's templating activity may help us in the prevention and development of novel therapeutic strategies for neurodegenerative diseases.

Using co-axial electrospray deposition to eliminate burst release of simvastatin from microparticles and to enhance induced osteogenesis

Microparticles (MPs) exhibit fast dissolution, characterized by a burst drug release pattern. In the present work, we prepared core-shell MPs of simvastatin (SIM) and zein with chitosan (CS) and nano-hydroxyapatite (nHA) as a drug carrier using the coaxial electrospray deposition method. The morphology, formation and in vitro osteogenic differentiation of these MPs were studied. The synthetic MPs have a diameter of about 1 μm and they are composed of non-toxic natural materials. They provide an effective way to enable long-term sustained-release activity, which is controlled by their double layer structures. The CS-nHA/zein-SIM MPs presented a low initial burst release (approximately 35-47%) within the first 24 h of application followed by the sustained release for at least 4 weeks. In vitro cell culture experiments were performed and the results revealed that the CS-nHA/zein-SIM core-shell MPs were beneficial to the adhesion, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). The CS-nHA/zein-SIM MPs with a low SIM concentration were beneficial to cell proliferation and promotion of osteogenic differentiation.

Satellite cells fail to contribute to muscle repair but are functional in Pompe disease (glycogenosis type II)

Pompe disease, which is due to acid alpha-glucosidase deficiency, is characterized by skeletal muscle dysfunction attributed to the accumulation of glycogen-filled lysosomes and autophagic buildup. Despite the extensive tissue damages, a failure of satellite cell (SC) activation and lack of muscle regeneration have been reported in patients. However, the origin of this defective program is unknown. Additionally, whether these deficits occur gradually over the disease course is unclear. Using a longitudinal pathophysiological study of two muscles in a Pompe mouse model, here, we report that the enzymatic defect results in a premature saturating glycogen overload and a high number of enlarged lysosomes. The muscles gradually display profound remodeling as the number of autophagic vesicles, centronucleated fibers, and split fibers increases and larger fibers are lost. Only a few regenerated fibers were observed regardless of age, although the SC pool was preserved. Except for the early age, during which higher numbers of activated SCs and myoblasts were observed, no myogenic commitment was observed in response to the damage. Following in vivo injury, we established that muscle retains regenerative potential, demonstrating that the failure of SC participation in repair is related to an activation signal defect. Altogether, our findings provide new insight into the pathophysiology of Pompe disease and highlight that the activation signal defect of SCs compromises muscle repair, which could be related to the abnormal energetic supply following autophagic flux impairment.

Validation of a clinically-relevant rodent model of statin-associated muscle symptoms for use in pharmacological studies

Various rodent models of statin-associated muscle symptoms (SAMS) have been used to investigate the aetiology of statin myotoxicity. Variability between these models, however, may be contributing to the ambiguity currently surrounding the pathogenesis of SAMS. Furthermore, few studies have assessed the reproducibility of these models. The aim of this study was to compare two established rodent models of statin myotoxicity, differing in treatment duration and dose, to determine which reproducibly caused changes characteristic of SAMS. Isolated skeletal muscle organ bath experiments, biochemical analyses, real-time quantitative-PCR and biometric assessments were used to compare changes in skeletal muscle and renal integrity in statin-treated animals and time-matched control groups. The SIM80 model (80 mg kg^-1 day^-1 simvastatin for 14 days) produced fibre-selective skeletal muscle damage characteristic of SAMS. Indeed, fast-twitch gastrocnemius muscles showed increased Atrogin-1 expression, reduced peak force of contraction and decreased Myh2 expression while slow-twitch soleus muscles were unaffected. Contrastingly, the SIM50 model (50 mg kg^-1 day^-1 simvastatin for 30 days) produced little evidence of significant skeletal muscle damage. Neither statin treatment protocol caused significant pathological changes to the kidney. The results of this study indicate that the SIM80 model induces a type of SAMS in rodents that resembles the presentation of statin-induced myalgia in humans. The findings support that the SIM80 model is reproducible and can thus be reliably used as a platform to assess the aetiology and treatment of this condition.

Effect of L-carnitine on the skeletal muscle contractility in simvastatin-induced myopathy in rats

Background

Statins therapy is effective in the prevention of cardiovascular events. However, its use is associated with skeletal muscle myopathy, which may be severe enough to discontinue statin therapy, thus exposing patients to more morbidity and mortality. This study was conducted to assess the effect of L-carnitine on the skeletal muscle contractility in a rat model of statin-induced myopathy and to clarify its possible mechanisms.

Methods

Twenty-one female Sprague Dawley rats were used throughout this study. The rats were divided into the normal control group, statin-induced myopathy group and statin/L-carnitine-treated group. The assessment of gastrocnemius muscle contractility, plasma creatine kinase (CK) levels and oxidative stress markers (malondialdehyde, reduced glutathione) was also carried out done.

Results

The results of the current study suggest that simvastatin decreased the skeletal muscle mass and altered the muscle contractile properties. It also significantly increased plasma CK level and induced a state of oxidative stress state (high MDA, low GSH). Meanwhile, concurrent L-carnitine significantly reduced statin-induced myopathy and improved the oxidative stress markers and skeletal muscle contractile parameters.

Conclusions

Statin myopathy is postulated to be due to mitochondrial dysfunction, cellular oxidative stress, induction of apoptosis, reduction in the expression of chloride channel and its related conductance, in addition to the alteration of Ca2+ homeostasis. L-carnitine has an antioxidant effect, reduces skeletal muscle atrophy and improves the skeletal muscle contractility in simvastatin-induced myopathy.

Toxicity impact of fenvalerate on the gill tissue of Oreochromis mossambicus with respect to biochemical changes utilizing FTIR and principal component analysis

The use of pesticides in agriculture can make their way into the earth and wash into the amphibian system causing ecological stress. This study aims to understand the changes occurring in gill tissues as a result of fenvalerate exposure using Fourier-transform infrared spectroscopy. The intensity ratio of the selected bands I1545/I1657, I2924/I2853, and I1045/I1545 measures changes in proteins, lipids, and carbohydrates. Curve-fitting analysis was performed in the selected band region to analyze the quantitative changes of proteins, lipids, and carbohydrates. The band area ratio of CH3/asCH2+ sCH2 shows the absence of a long chain of fatty acids due to fenvalerate treatment. The band area ratio of asCH2/sCH2 increases for higher sublethal concentrations, which shows the lower disorder of lipid acyl chain flexibility. A decrease in lipids was found in lower sublethal concentrations. The secondary structure of proteins affirms β sheet development. Carbohydrate metabolism of gill tissues demonstrates a decrease in glycogen contents. A further decrease in glycogen content and an increase in lactic acid were observed when presented to a fenvalerate concentration. PCA plots indicate distinct variations among the biochemical parameters of the gill tissues. This study provides a quantitative examination of assessing pesticide toxicity in aquatic environments.

The complexation of rhizosphere and nonrhizosphere soil organic matter with chromium: Using elemental analysis combined with FTIR spectroscopy

Complexation is a main mechanism controlling the reactions between soil organic matter (SOM) and heavy metals, which still have not been fully understood up to date. The objective of this study was to compare the SOM composition of nonrhizosphere and rhizosphere in low Cr treatment with that in high Cr treatment and to find out how metal concentrations affect the complexation with SOM. The results revealed that both the hydroxyl and the carboxyl were significantly different under different Cr treatment groups. For nonrhizosphere samples, the high Cr treatment tended to have less hydroxyl contents and more structural changes on hydroxyl (3389-3381 cm^-1) than the low Cr treatment (3389-3388 cm^-1), while in the rhizosphere samples the reverse happened. The gap of the different Cr treated band area in the rhizosphere samples (44 a.u of the gap) was greatly smaller than that in the nonrhizosphere samples (576 a.u of the gap). In both the rhizosphere and nonrhizosphere samples, the high Cr treatment showed greater structural changes on carboxylic acids (11, 12 a.u changes based on the control) than the low Cr treatment (4, 6 a.u). The unsaturated carboxylic acids could account for downward frequency shift and the contents in the nonrhizosphere samples were slightly greater than that in the rhizosphere samples. This study used elemental analysis combined with FTIR spectroscopy to explore the effects of metal concentrations on the complexation of Cr with SOM and the composition of SOM. These findings give a way to understanding part of the complexation mechanisms between the metal and SOM.

Phenotype-Specific Response of Circulating miRNAs Provides New Biomarkers of Slow or Fast Muscle Damage

Skeletal muscle is a heterogeneous tissue composed of a continuum of contracting fibers ranging from slow-type to fast-type fibers. Muscle damage is a frequent event and a susceptibility of fast-fibers to exercise-induced damage (EIMD) or statins toxicity has been reported. Biological markers of muscle damage such as creatine kinase (CK) are not fiber-type specific and new biomarkers are needed. Some microRNAs (miRNAs) are specific to the muscle tissue, can be found in the extracellular compartment and can rise in the plasma following muscle damage. Our aim was to identify whether a set of circulating miRNAs can be used as fiber-type specific biomarkers of muscle damage in a model of traumatic (crush) injuries induced either in the slow soleus (SOL) or in the fast extensor digitorum longus (EDL) muscles of rats. A subset of miRNAs composed of miR-1-3p, -133a-3p, -133b-3p, 206-3p, -208b-3p, 378a-3p, -434-3p, and -499-5p were measured by RT-PCR in non-injured SOL or EDL muscle and in the plasma of rats 12 h after damage induced to SOL or EDL. MiR-133b-3p, -378a-3p, and -434-3p were equally expressed both in SOL and EDL muscles. MiR-1-3-p and -133a-3p levels were higher in EDL compared to SOL (1.3- and 1.1-fold, respectively). Conversely, miR-206-3p, -208b-3p, and -499-5p were mainly expressed in SOL compared to EDL (7.4-, 35.4-, and 10.7-fold, respectively). In the plasma, miR-1-3p and -133a-3p were elevated following muscle damage compared to a control group, with no difference between SOL and EDL. MiR-133b-3p and -434-3p plasma levels were significantly higher in EDL compared to SOL (1.8- and 2.4-fold, respectively), while miR-378a-3p rose only in the EDL group. MiR-206-3p levels were elevated in SOL only (fourfold compared to EDL). Our results show that plasma miR-133b-3p and -434 are fast-fiber specific biomarkers, while miR-206-3p is a robust indicator of slow-fiber damage, opening new perspectives to monitor fiber-type selective muscle damage in research and clinic.

Relapsing-Remitting Multiple Sclerosis diagnosis from cerebrospinal fluids via Fourier transform infrared spectroscopy coupled with multivariate analysis

Multiple sclerosis (MS) is a chronic, progressive, inflammatory and degenerative disease of central nervous system. Here, we aimed to develop a method for differential diagnosis of Relapsing-Remitting MS (RRMS) and clinically isolated syndrome (CIS) patients, as well as to identify CIS patients who will progress to RRMS, from cerebrospinal fluid (CSF) by infrared (IR) spectroscopy and multivariate analysis. Spectral analyses demonstrated significant differences in the molecular contents, especially in the lipids and Z conformation of DNA of CSF from CIS, CIS to RRMS transformed (TCIS) and RRMS groups. These changes enables the discrimination of diseased groups and controls (individuals with no neurological disease) from each other using hierarchical cluster and principal component analysis. Some CIS samples were consistently clustered in RRMS class, which may indicate that these CIS patients potentially will transform to RRMS over time. Z-DNA band at 795 cm⁻¹ that is existent only in diseased groups and significant increase in carbonyl amount, decrease in amideI/amide II and lipid/protein ratios observed only for RRMS groups can be used as diagnostic biomarkers. The results of the present study shed light on the early diagnosis of RRMS by IR spectroscopy complemented with multivariate analysis tools.

Anti-obesity effects of yellow catfish protein hydrolysate on mice fed a 45% kcal high-fat diet

Obesity contributes to the etiologies of a variety of comorbid conditions, such as type 2 diabetes, hypertension and cardiovascular disease. In the present study, the anti-obesity effects of yellow catfish protein hydrolysate (YPh) were observed in mice fed a 45% kcal high-fat diet (HFD) compared with those of mice treated with simvastatin. The HFD-fed control mice exhibited noticeable increase in body weight, and whole-body and abdominal fat densities, periovarian and abdominal wall-deposited fat pad weight, as well as in the levels of triglycerides (TG), blood total cholesterol (TC), low-density lipoprotein, alanine aminotransferase, aspartate aminotransferase, creatinine, blood urea nitrogen, and in the fecal TG and TC contents. However, they exhibited a decrease in serum high-density lipoprotein levels. In addition, an increase was detected in periovarian and dorsal abdominally deposited fat pad thickness, adipocyte hypertrophy, the number of steatohepatitis regions, hepatocyte hypertrophy and lipid droplet deposition-related renal tubular vacuolation degenerative lesions, along with increased hepatic lipid peroxidation and a deteriorated endogenous antioxidant defense system (glutathione, catalase and superoxide dismutase). However, all the above-mentioned obesity-related complications were dose-dependently and significantly inhibited after 84 days of thye consecutive oral administration of 125, 250 and 500 mg/kg YPh. In addition, YPh dose-dependently depleted the liver endogenous antioxidant defense system and inhibited hepatic lipid peroxidation. Overall, the effects of 250 mg/kg YPh on HFD-induced obesity and related complications were similar or more potent than those of 10 mg/kg simvastatin. These results indicate that YPh is a promising new potent medicinal ingredient for possible use in the treatment of obesity and related complications.

[Direct mechanism of action in toxic myopathies]

Toxic myopathies are a large group of disorders generated by surrounding agents and characterized by structural and/or functional disturbances of muscles. The most recurrent are those induced by commonly used medications. Illicit drugs, environmental toxins from animals, vegetables, or produced by micro-organisms as well as chemical products commonly used are significant causes of such disorders. The muscle toxicity results from multiple mechanisms at different biological levels. Many agents can induce myotoxicity through a direct mechanism in which statins, glucocorticoids and ethyl alcohol are the most representative. Diverse mechanisms were highlighted as interaction with macromolecules and induction of metabolic and cellular dysfunctions. Muscle damage can be related to amphiphilic properties of some drugs (chloroquine, hydroxychloroquine, etc.) leading to specific lysosomal disruptions and autophagic dysfunctions. Some agents affect the whole muscle fiber by inducing oxidative stress (ethyl alcohol and some statins) or triggering cell death pathways (apoptosis or necrosis) resulting in extensive alterations. More studies on these mechanisms are needed. They would allow a better knowledge of the intracellular mediators involved in these pathologies in order to develop targeted therapies of high efficiency.

A short-term statin treatment changes the contractile properties of fast-twitch skeletal muscles

Background

Cumulative evidence indicates that statins induce myotoxicity. However, the lack of understanding of how statins affect skeletal muscles at the structural, functional, and physiological levels hampers proper healthcare management. The purpose of the present study was to investigate the early after-effects of lovastatin on the slow-twitch soleus (Sol) and fast-twitch extensor digitorum longus (EDL) muscles.

Methods

Adult C57BL/6 mice were orally administrated with placebo or lovastatin [50 mg/kg/d] for 28 days. At the end of the treatment, the isometric ex vivo contractile properties of the Sol and EDL muscles were measured. Subtetanic and tetanic contractions were assessed and contraction kinetics were recorded. The muscles were then frozen for immunohistochemical analyses. Data were analyzed by two-way ANOVA followed by an a posteriori Tukey’s test.

Results

The short-term lovastatin treatment did not induce muscle mass loss, muscle fiber atrophy, or creatine kinase (CK) release. It had no functional impact on slow-twitch Sol muscles. However, subtetanic stimulations at 10 Hz provoked greater force production in fast-twitch EDL muscles. The treatment also decreased the maximal rate of force development (dP/dT) of twitch contractions and prolonged the half relaxation time (1/2RT) of tetanic contractions of EDL muscles.

Conclusions

An early short-term statin treatment induced subtle but significant changes in some parameters of the contractile profile of EDL muscles, providing new insights into the selective initiation of statin-induced myopathy in fast-twitch muscles.

Structural and functional damages of whole body ionizing radiation on rat brain homogenate membranes and protective effect of amifostine

PURPOSE

To investigate the effects of whole body ionizing radiation at a sublethal dose on rat brain homogenate membranes and the protective effects of amifostine on these systems at molecular level.

MATERIALS AND METHODS

Sprague-Dawley rats, in the absence and presence of amifostine, were whole-body irradiated at a single dose of 8 Gy and decapitated after 24 h. The brain homogenate membranes of these rats were analyzed using Fourier Transform Infrared (FTIR) spectroscopy.

RESULTS

Ionizing radiation caused a significant increase in the lipid to protein ratio and significant decreases in the ratios of olefinic = CH/lipid, CH₂/lipid, carbonyl ester/lipid and CH₃/lipid suggesting, respectively, a more excessive decrease in the protein content and the degradation of lipids as a result of lipid peroxidation. In addition, radiation changed the secondary structure of proteins and the status of packing of membrane lipid head groups. Furthermore, it caused a decrease in lipid order and an increase in membrane fluidity. The administration of amifostine before ionizing radiation inhibited all the radiation-induced alterations in brain homogenate membranes.

CONCLUSIONS

The results revealed that whole body ionizing radiation at a sublethal dose causes significant alterations in the structure, composition and dynamics of brain homogenate membranes and amifostine has a protective effect on these membranes.

Statin-associated myopathy and the quest for biomarkers: can we effectively predict statin-associated muscle symptoms?

Over the past three decades, statins have become the cornerstone of prevention and treatment of atherosclerotic cardiovascular and metabolic diseases. Albeit generally well tolerated, these drugs can elicit a variety of muscle-associated symptoms that represent the most important reason for treatment discontinuation. Statin-associated myopathy has been systematically underestimated by randomized controlled trials as compared with the incidence observed in clinical practice and obtained from patient registries. There are several reasons for this discrepancy, among which the lack of reliable diagnostic tests and a validated questionnaire to assess muscle symptoms are recognized as unmet needs. Here, we review the cellular and molecular mechanisms underlying statin-associated myopathy and discuss the experimental and clinical data on various biomarkers to diagnose and predict muscle-related complaints.

Differentiation of Chronic and Aggressive Periodontitis by FTIR Spectroscopy

Without longitudinal clinical data, it is difficult to differentiate some cases of chronic periodontitis (CP) and aggressive periodontitis (AgP). Furthermore, both forms of disease are exacerbated by tobacco use. Therefore, this cross-sectional study was planned, primarily, to determine the ability of Fourier-transform infrared (FTIR) spectroscopy to distinguish CP and AgP patients by analysis of human saliva samples and, secondarily, to assess the potential confounding influence of smoking on discriminating disease-specific spectral signatures. FTIR spectra were collected from patients with a clinical diagnosis of CP (n = 18; 7 smokers) or AgP (n = 23; 9 smokers). Self-reported smoking status, which may be unreliable, was confirmed by salivary cotinine analysis. Spectral band area analysis and hierarchical cluster analyses were performed to clarify if the 2 periodontitis groups as well as smoker and nonsmoker patients could be differentiated from each other. Significant variations in lipid, amino acid, lactic acid, and nucleic acid content were found between nonsmoker CP and AgP groups. Although significantly lower lipid, phospholipid, protein, amino acid, lactic acid, and nucleic acid content was noted in the smoker AgP group compared with the nonsmoker AgP group, in the CP group, phospholipid, protein, amino acid, and lactic acid content was significantly lower for smokers compared with the nonsmokers. Based on these variations, nonsmoker CP and AgP patients were discriminated from each other with high sensitivity and specificity. Successful differentiation was also obtained for the smoker CP and AgP groups. Thiocyanate levels successfully differentiated smokers from nonsmokers, irrespective of periodontal status, with 100% accuracy. Differentiation of AgP and CP forms, concomitant with determination of smoking status, may allow the dental health professional to tailor treatment accordingly.

Individual and combined toxic effect of nickel and chromium on biochemical constituents in E. coli using FTIR spectroscopy and Principle component analysis

Ni and Cr are ubiquitous pollutants in the aquatic environments. These heavy metals elicit toxicities to aquatic organisms including microbes. In this study, interaction of the two heavy metals on the toxicity in Escherichia coli (E. coli) was studied using FTIR spectroscopy. The binding of Ni(II) to E. coli was stronger than that for Cr(VI). Cr exhibited antagonistic effects in the presence of Ni in E. coli. FTIR analysis showed a decrease in lipid content in the presence of Ni and not for Cr. Further, a decrease in band area was observed in the region of 3000-2800cm(-1) and at ~1455cm(-1) due to a decrease in fatty acids and lipid molecules. The band area ratio of lipid was used to monitor the changes in fatty acids due to metal toxicity. Principle component method helps to discriminates the results between control and metal toxicities in E. coli from the FTIR data. The study shows the importance of metal interaction and its toxicity on E. coli.

Structural effects of simvastatin on liver rat [corrected] tissue: Fourier transform infrared and Raman microspectroscopic studies

Simvastatin is one of the most frequently prescribed statins because of its efficacy in the treatment of hypercholesterolemia, reducing cardiovascular risk and related mortality. Determination of its side effects on different tissues is mandatory to improve safe use of this drug. In the present study, the effects of simvastatin on molecular composition and structure of healthy rat livers were investigated by Fourier transform infrared and Raman imaging. Simvastatin-treated groups received 50 mg/kg/day simvastatin for 30 days. The ratio of the area and/or intensity of the bands assigned to lipids, proteins, and nucleic acids were calculated to get information about the drug-induced changes in tissues. Loss of unsaturation, accumulation of end products of lipid peroxidation, and alterations in lipid-to-protein ratio were observed in the treated group. Protein secondary structure studies revealed significant decrease in α-helix and increase in random coil, while native β-sheet decreases and aggregated β-sheet increases in treated group implying simvastatin-induced protein denaturation. Moreover, groups were successfully discriminated using principal component analysis. Consequently, high-dose simvastatin treatment induces hepatic lipid peroxidation and changes in molecular content and protein secondary structure, implying the risk of liver disorders in drug therapy.

The pharmacokinetic characters of simvastatin after co-administration with Shexiang Baoxin Pill in healthy volunteers' plasma

To investigate the effect of Shexiang Baoxin Pill (SBP), a tranditional Chinese medicine, on the pharmacokinetic (PK) parameters of simvastatin in healthy volunteers' plasma, a quantitative method was developed using an Agilent G6410A rapid performance liquid chromatography (RPLC) coupled with triple quadrupole mass spectrometry system. The established method was rapid with high extraction recovery and successfully applied for the determination of simvastatin in plasma of 16 healthy volunteers. The results demonstrated that the MRT(0-∞), T1/2 and Tmax value of simvastatin were significantly decreased, while the AUC(0-t) and Cmax values of smivastatin were increased by SBP. The pharmacokinetic study demonstrated that the metabolism parameters of simvastatin could be affected by SBP and the potential drug-drug interaction should be noted in the future clinical practice.

Skeletal muscle ultrastructure and function in statin-tolerant individuals

INTRODUCTION

Statins have well-known benefits on cardiovascular mortality, though up to 15% of patients experience side effects. With guidelines from the American Heart Association, American College of Cardiology, and American Diabetes Association expected to double the number of statin users, the overall incidence of myalgia and myopathy will increase.

METHODS

We evaluated skeletal muscle structure and contractile function at the molecular, cellular, and whole tissue levels in 12 statin tolerant and 12 control subjects.

RESULTS

Myosin isoform expression, fiber type distributions, single fiber maximal Ca(2+) -activated tension, and whole muscle contractile force were similar between groups. No differences were observed in myosin-actin cross-bridge kinetics in myosin heavy chain I or IIA fibers.

CONCLUSIONS

We found no evidence for statin-induced changes in muscle morphology at the molecular, cellular, or whole tissue levels. Collectively, our data show that chronic statin therapy in healthy asymptomatic individuals does not promote deleterious myofilament structural or functional adaptations.

Fluvastatin delays propagation of viral infection in isolated rat FDB myofibers but does not affect exocytic membrane trafficking

We have utilized the enveloped viral model to study the effect of fluvastatin on membrane trafficking in isolated rat myofibers. Our immunofluorescence studies constantly showed that infections in myofibers, which were treated with fluvastatin prior and during the infection with either vesicular stomatitis virus (VSV) or influenza A virus, propagated more slowly than in control myofibers without drug treatment. Experiments with a virus expressing Dad1 tagged with green fluorescent protein (GFP-Dad1) showed that fluvastatin did not affect its distribution within the ER/SR network and immunofluorescence staining for GM130 did not show any marked effect on the structure of the Golgi components. Furthermore, fluvastatin did not inhibit trafficking of the chimeric transport marker VSV temperature sensitive G protein (tsG-GFP) from the ER to the Golgi. We next subjected VSV infected myofibers for pulse-chase labeling experiments and found that fluvastatin did not slow down the ER-to-Golgi trafficking or Golgi to plasma membrane trafficking of the viral glycoprotein. These studies show that fluvastatin inhibited the propagation of viral infection in skeletal myofibers but no adverse effect on the exocytic trafficking could be demonstrated. These results suggest that other effects of statins rather than inhibition of ER-to-Golgi trafficking might be behind the myotoxic effects of the statins.

An assessment by the Statin Muscle Safety Task Force: 2014 update

The National Lipid Association's Muscle Safety Expert Panel was charged with the duty of examining the definitions for statin-associated muscle adverse events, development of a clinical index to assess myalgia, and the use of diagnostic neuromuscular studies to investigate muscle adverse events. We provide guidance as to when a patient should be considered for referral to neuromuscular specialists and indications for the performance of a skeletal muscle biopsy. Based on this review of evidence, we developed an algorithm for the evaluation and treatment of patients who may be intolerant to statins as the result of adverse muscle events. The panel was composed of clinical cardiologists, clinical lipidologists, an exercise physiologist, and a neuromuscular specialist.

FTIR spectroscopy offers hints towards widespread molecular changes in cobalt-acclimated freshwater bacteria

High concentrations of heavy metals can be toxic for bacteria. However, after prolonged exposure, bacteria can become acclimated and begin to be able to grow in the presence of heavy metals. Acclimation can involve alterations of metabolism and molecular structures. Our aim was to examine these alterations in cobalt-acclimated bacteria via attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy on viable samples. Bacillus sp. and Pseudomonas sp. isolated from a temperate shallow lake and a well-established strain of E. coli were investigated. Our results revealed consistent, wide-spread changes in cell membrane and cell wall dynamics of Bacillus sp. and E. coli, including a decrease in peptidoglycan content of Bacillus sp. and increased lipid ordering of the membrane in both bacteria. Furthermore, a decrease in RNA and protein concentrations of Bacillus sp. was measured. All three bacteria studied showed a decrease in conformational freedom of proteins following cobalt acclimation. Interestingly, both Bacillus sp. and E. coli showed slight but significant alterations in their DNA conformations which might imply a methylation-mediated memory formation leading to epigenetic modulation for cobalt adaptation.

Statins and skeletal muscles toxicity: from clinical trials to everyday practice

The mechanism(s) underlying the occurrence of statin-induced myopathy are ill defined, but the results of observational studies and clinical trials provide compelling evidence that skeletal muscle toxicity is a frequent, dose-dependent, adverse event associated with all statins. It has been suggested that reduced availability of metabolites produced by the mevalonate pathway rather than intracellular cholesterol lowering per se might be the primary trigger of toxicity, however other alternative explanations have gained credibility in recent years. Aim of this review is: (i) to describe the molecular mechanisms associated to statin induced myopathy including defects in isoprenoids synthesis followed by altered prenylation of small GTPase, such as Ras and Rab proteins; (ii) to present the emerging aspects on pharmacogenetics, including CYP3A4, OATP1B1 and glycine amidinotransferase (GATM) polymorphisms impacting either statin bioavailability or creatine synthesis; (iii) to summarize the available epidemiological evidences; and (iii) to discuss the concepts that would be of interest to the clinicians for the daily management of patients with statin induced myopathy. The interplay between drug-environment and drug-drug interaction in the context of different genetic settings contribute to statins and skeletal muscles toxicity. Until specific assays/algorithms able to combine genetic scores with drug-drug-environment interaction to identify patients at risk of myopathies will become available, clinicians should continue to monitor carefully patients on polytherapy which include statins and be ready to reconsider dose, statin or switching to alternative treatments. The beneficial effects of adding agents to provide the muscle with the metabolites, such as CoQ10, affected by statin treatment will also be addressed.

Simvastatin treatment attenuates increased respiratory variability and apnea/hypopnea index in rats with chronic heart failure

Cheyne-Stokes respiration and cardiac arrhythmias are associated with increased morbidity and mortality in patients with chronic heart failure (CHF). Enhanced carotid body chemoreflex (CBC) sensitivity is associated with these abnormalities in CHF. Reduced carotid body (CB) nitric oxide and nitric oxide synthase (NOS) levels play an important role in the enhanced CBC. In other disease models, Simvastatin (statin) treatment increases endothelial NOS, in part, by increasing Krüppel-like Factor 2 expression. We hypothesized that statin treatment would ameliorate enhanced CBC sensitivity as well as increased respiratory variability, apnea/hypopnea index, and arrhythmia index, in a rodent model of CHF. Resting breathing pattern, cardiac rhythm, and the ventilatory and CB chemoreceptor afferent responses to hypoxia were assessed in rats with CHF induced by coronary ligation. CHF was associated with enhanced ventilatory and CB afferent responses to hypoxia as well as increased respiratory variability, apnea/hypopnea index, and arrhythmia index. Statin treatment prevented the increases in CBC sensitivity and the concomitant increases in respiratory variability, apnea/hypopnea index, and arrhythmia index. Krüppel-like Factor 2 and endothelial NOS protein were decreased in the CB and nucleus tractus solitarii of CHF animals, and statin treatment increased the expression of these proteins. Our findings demonstrate that the increased CBC sensitivity, respiratory instability, and cardiac arrhythmias observed in CHF are ameliorated by statin treatment and suggest that statins may be an effective treatment for Cheyne-Stokes respiration and arrhythmias in patient populations with high chemoreflex sensitivity.