Gemfibrozil, stretching arms beyond lipid lowering

Transcriptional modulation in Mediterranean Mussel Mytilus galloprovincialis following exposure to four pharmaceuticals widely distributed in coastal areas

Ecotoxicological risk and the mode of action of human drugs on non-target marine animals remain unclear, keeping a gap of knowledge on risks related to ecosystem disruption and chemical contamination of food chains. Understanding these impacts is critical to developing proper waste management practices and regulatory frameworks to prevent long-term environmental and human health problems. This study investigates the impacts of Gemfibrozil, Metformin, Ramipril, and Venlafaxine, individually and combined on Mytilus galloprovincialis over 30 days and assesses persistent effects post-recovery using RNA-seq and 16S rRNA microbiota profiling. All pharmaceuticals caused few changes in the microbiota while gene expression analyses highlighted drug-specific alterations. Gemfibrozil exposure led to alterations in lipid and fatty acid metabolism, suggesting a similar mode of action to that observed in target species. Metformin significantly impacted the mussels' energy metabolism, with disruptions in specific genes and pathways potentially related to glucose uptake and insulin signaling. Metformin was also the treatment leading to the most significant changes in predicted functional profiles of the microbiota, suggesting that it may influence the microbiota's potential to interact with host glucose metabolism. Ramipril exposure resulted in the up-regulation of stress response and cell cycle regulation pathways and Venlafaxine induced changes in serotonin and synapse pathways, indicating potential similarities in mechanisms of action with target species. Mixture of the four pharmaceuticals severely impacted mussel physiology, including impairment of oxidative phosphorylation and compensatory activation of several pathways involved in energy metabolism. Despite recovery after depuration, changes in stress and energy related metabolism pathways suggests potential persistent effects from combined pharmaceutical exposure. Notably, the up-regulation of mTOR1 signaling in all treatments after 30 days underscores its key role in coordinating bivalve stress responses. The Transcriptomic Hazard Index (THI) calculated for each treatment indicates major/severe hazards after exposure that decreased to slight/moderate hazards after depuration.

Iterative One-Carbon Homologation of Unmodified Carboxylic Acids

The one-carbon homologation of carboxylic acids is a valuable route to construct families of homologues, which play fundamental roles in chemistry and biology. However, known procedures are based on multistep sequences, use harsh conditions or are limited in scope. Thus, almost a century after the discovery of the original Arndt-Eistert homologation sequence, a general method to directly convert carboxylic acids into their corresponding homologues remains elusive. Exploiting the photoredox reactivity of nitroethylene, we disclose a practical visible-light-induced homologation of unmodified carboxylic acids. Iterations of the procedure reveal an exceptionally tunable strategy for the construction of inert carbon spacers, opening new opportunities in synthesis.

Gemfibrozil Improves Microcirculatory Oxygenation of Colon and Liver without Affecting Mitochondrial Function in a Model of Abdominal Sepsis in Rats

Recent studies observed, despite an anti-hyperlipidaemic effect, a positive impact of fibrates on septic conditions. This study evaluates the effects of gemfibrozil on microcirculatory variables, mitochondrial function, and lipid peroxidation levels with regard to its potential role as an indicator for oxidative stress in the colon and liver under control and septic conditions and dependencies on PPARα-mediated mechanisms of action. With the approval of the local ethics committee, 120 Wistar rats were randomly divided into 12 groups. Sham and septic animals were treated with a vehicle, gemfibrozil (30 and 100 mg/kg BW), GW 6471 (1 mg/kg BW, PPARα inhibitor), or a combination of both drugs. Sepsis was induced via the colon ascendens stent peritonitis (CASP) model. Then, 24 h post sham or CASP surgery, a re-laparotomy was performed. Measures of vital parameters (heart rate (HR), mean arterial pressure (MAP), and microcirculation (µHbO2)) were recorded for 90 min. Mitochondrial respirometry and assessment of lipid peroxidation via a malondialdehyde (MDA) assay were performed on colon and liver tissues. In the untreated sham animals, microcirculation remained stable, while pre-treatment with gemfibrozil showed significant decreases in the microcirculatory oxygenation of the colon. In the CASP animals, µHbO2 levels in the colon and the liver were significantly decreased 90 min after laparotomy. Pre-treatment with gemfibrozil prevented the microcirculatory aberrations in both organs. Gemfibrozil did not affect mitochondrial function and lipid peroxidation levels in the sham or CASP animals. Gemfibrozil treatment influences microcirculation depending on the underlying condition. Gemfibrozil prevents sepsis-induced microcirculatory aberrances in the colon and liver PPARα-independently. In non-septic animals, gemfibrozil impairs the microcirculatory variables in the colon without affecting those in the liver.

Exploring the mechanism of action of Hedyotis diffusa Willd on acne using network analysis

In this study, we used a network pharmacological method to explore the active ingredients of Hedyotis diffusa Willd (HDW) in the treatment of acne and elucidated the physiological mechanisms in the human body in which they are involved. We identified the active compounds of HDW that are expected to act effectively in the human body using the Traditional Chinese Medicine Systems Pharmacology database and analysis platform and extracted potential interacting proteins for each active compound using the Swiss Target Prediction platform. Next, we analyzed the potential mechanisms of action of the protein targets shared by HDW and each standard drug on acne and assessed the possibility of spontaneous occurrence of the binding between proteins and active compounds through the molecular docking process. Seven active compounds were selected according to the oral bioavailability and drug-likeness criteria of the Traditional Chinese Medicine Systems Pharmacology database and analysis platform. Subsequently, 300 protein targets were collected from the Swiss Target Prediction. Using the Search Tool for the Retrieval of Interacting Genes/Proteins database, a protein-protein interaction network was constructed by analyzing the relationship between HDW, acne, and each standard drug. By analyzing the gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathway, the "positive regulation of lipid metabolic process" was found to be the most involved pathway shared by HDW, acne, and isotretinoin. An analysis of the protein targets shared by the antibiotic agents with HDW and acne found that "cholesterol storage" in tetracycline, "icosacoid transport" in azithromycin, "steroid hydroxylase activity" in erythromycin, "positive regulation of leukocyte tethering or rolling" in clindamycin, "response to UV-A" in minocycline, "steroid 11-beta-monooxygenase activity" in doxycycline, and "neutrophil-mediated immunity" in trimethoprim were the most involved. Virtual molecular docking analysis showed that all proteins spontaneously bound to their corresponding active compounds. Our analysis suggests that HDW can, directly and indirectly, suppress sebum secretion and exert antiinflammatory effects on acne. Further, HDW may regulate free radicals and suppress apoptosis. Therefore, HDW can be used as an alternative or supplement to standard drugs for acne treatment in patients who cannot use standard treatments due to side effects.

Activation of PPARα Exhibits Therapeutic Efficacy in a Mouse Model of Juvenile Neuronal Ceroid Lipofuscinosis

Juvenile neuronal ceroid lipofuscinosis (JNCL) is a fatal inherited neurodegenerative disease of children that occurs because of defective function of the lysosomal membrane glycoprotein CLN3. JNCL features glial activation and accumulation of autofluorescent storage material containing subunit c of mitochondrial ATP synthase (SCMAS), ultimately resulting into neuronal loss. Until now, no effective therapy is available for JNCL. This study underlines the possible therapeutic importance of gemfibrozil, an activator of peroxisome proliferator-activated receptor α (PPARα) and a lipid-lowering drug approved by the Food and Drug Administration in an animal model of JNCL. Oral gemfibrozil treatment reduced microglial and astroglial activation, attenuated neuroinflammation, restored the level of transcription factor EB (TFEB; the master regulator of lysosomal biogenesis), and decreased the accumulation of storage material SCMAS in somatosensory barrel field (SBF) cortex of Cln3Δex7/8 (Cln3ΔJNCL) mice of both sexes. Accordingly, gemfibrozil treatment also improved locomotor activities of Cln3ΔJNCL mice. While investigating the mechanism, we found marked loss of PPARα in the SBF cortex of Cln3ΔJNCL mice, which increased after gemfibrozil treatment. Oral gemfibrozil also stimulated the recruitment of PPARα to the Tfeb gene promoter in vivo in the SBF cortex of Cln3ΔJNCL mice, indicating increased transcription of Tfeb in the CNS by gemfibrozil treatment via PPARα. Moreover, disease pathologies aggravated in Cln3ΔJNCL mice lacking PPARα (Cln3ΔJNCLΔPPARα) and gemfibrozil remained unable to decrease SCMAS accumulation, reduce glial activation, and improve locomotor performance of Cln3ΔJNCLΔPPARα mice. These results suggest that activation of PPARα may be beneficial for JNCL and that gemfibrozil may be repurposed for the treatment of this incurable disease.SIGNIFICANCE STATEMENT Despite intense investigations, no effective therapy is available for JNCL, an incurable inherited lysosomal storage disorder. Here, we delineate that oral administration of gemfibrozil, a lipid-lowering drug, decreases glial inflammation, normalizes and/or upregulates TFEB, and reduces accumulation of autofluorescent storage material in SBF cortex to improve locomotor activities in Cln3Δex7/8 (Cln3ΔJNCL) mice. Aggravation of disease pathology in Cln3ΔJNCL mice lacking PPARα (Cln3ΔJNCLΔPPARα) and inability of gemfibrozil to decrease SCMAS accumulation, reduce glial activation, and improve locomotor performance of Cln3ΔJNCLΔPPARα mice delineates an important role of PPARα in this process. These studies highlight a new property of gemfibrozil and indicate its possible therapeutic use in JNCL patients.

Treadmill workout activates PPARα in the hippocampus to upregulate ADAM10, decrease plaques and improve cognitive functions in 5XFAD mouse model of Alzheimer's disease

Although liver is rich in peroxisome proliferator-activated receptor α (PPARα), recently we have described the presence of PPARα in hippocampus where it is involved in non-amyloidogenic metabolism of amyloid precursor protein (APP) via ADAM10, decreasing amyloid plaques and improving memory and learning. However, mechanisms to upregulate PPARα in vivo in the hippocampus are poorly understood. Regular exercise has multiple beneficial effects on human health and here, we describe the importance of regular mild treadmill exercise in upregulating PPARα in vivo in the hippocampus of 5XFAD mouse model of Alzheimer's disease. We also demonstrate that treadmill exercise remained unable to stimulate ADAM10, reduce plaque pathology and improve cognitive functions in 5XFADΔPPARα mice (5XFAD mice lacking PPARα). On the other hand, treadmill workout increased ADAM10, decreased plaque pathology and protected memory and learning in 5XFADΔPPARβ mice (5XFAD mice lacking PPARβ). Moreover, the other PPAR (PPARγ) also did not play any role in the transcription of ADAM10 in vivo in the hippocampus of treadmill exercised 5XFAD mice. These results underline an important role of PPARα in which treadmill exercise remains unable to exhibit neuroprotection in the hippocampus in the absence of PPARα.

Regioselective C(sp2)-H imidation of arenes by redox neutral visible-light photocatalysis

We report herein a redox neutral visible light-induced regioselective C(sp²)-H imidation of electron-rich arenes and heteroarenes using conceptually designed redox-active 1 as a source of the N-centered imidyl radical. Structurally diverse aromatic imides were obtained in moderate to good yields. This methodology has been successfully employed for the late stage imidation of complex molecules and has also been applied towards the formal total synthesis of the marine natural products carpatamides A, B and D. It has further been shown that the generated imides can easily be converted to the corresponding anilines in situ directly.

Gemfibrozil, a lipid-lowering drug, improves hepatorenal damages in a mouse model of aging

Gemfibrozil (GFZ) is a medication of the fibrate category with agonistic effects on peroxisome proliferator-activated receptor-α (PPAR-α) and is effective for hypertriglyceridemia and mixed dyslipidemia. This agent also has anti-inflammatory and antioxidant properties. The current study investigated the effects of GFZ on hepatorenal damages in a D-galactose (D-gal)-induced aging model. We used 28 male mice, which were equally and randomly divided into four groups as follows: normal, D-gal (150 mg/kg/day; intraperitoneal [i.p.], for 6 weeks), GFZ (100 mg/kg/day GFZ, orally [p.o.] for 6 weeks), and the combined D-gal + GFZ. Liver and kidney function indices were measured as serum creatinine, blood urine nitrogen, alanine aminotransferase, and aspartate aminotransferase. Oxidative stress in hepatic and renal tissue was evaluated through malondialdehyde, superoxide dismutase, and glutathione peroxidase levels. Finally, the liver and kidney tissues were assessed for histopathological lesions. The results showed that D-gal-induced aging leads to abnormalities in liver and kidney function indices. D-gal also induced significant oxidative stress and histopathological lesions in these organs. GFZ improved function indices and oxidative stress compared to the D-gal-treated animals. Histological evaluations of the liver and kidney also confirmed these results. These data provide evidence for the potential therapeutic of GFZ in clinical practice for mitigating the hepatorenal damages of aging.

Current Understanding on the Role of Lipids in Macrophages and Associated Diseases

Lipid metabolism is the major intracellular mechanism driving a variety of cellular functions such as energy storage, hormone regulation and cell division. Lipids, being a primary component of the cell membrane, play a pivotal role in the survival of macrophages. Lipids are crucial for a variety of macrophage functions including phagocytosis, energy balance and ageing. However, functions of lipids in macrophages vary based on the site the macrophages are residing at. Lipid-loaded macrophages have recently been emerging as a hallmark for several diseases. This review discusses the significance of lipids in adipose tissue macrophages, tumor-associated macrophages, microglia and peritoneal macrophages. Accumulation of macrophages with impaired lipid metabolism is often characteristically observed in several metabolic disorders. Stress signals differentially regulate lipid metabolism. While conditions such as hypoxia result in accumulation of lipids in macrophages, stress signals such as nutrient deprivation initiate lipolysis and clearance of lipids. Understanding the biology of lipid accumulation in macrophages requires the development of potentially active modulators of lipid metabolism.

Sexual dimorphism in immune cell responses following stroke

Recent bodies of work in regard to stroke have revealed significant sex differences in terms of risk and outcome. While differences in sex hormones have been the focus of earlier research, the reasons for these differences are much more complex and require further identification. This review covers differences in sex related immune responses with a focus on differences in immune cell composition and function. While females are more susceptible to immune related diseases, they seem to have better outcomes from stroke at the experimental level with reduced pro-inflammatory responses. However, at the clinical level, the picture is much more complex with worse neurological outcomes from stroke. While the use of exogenous sex steroids can replicate some of these findings, it is apparent that many other factors are involved in the modulation of immune responses. As a result, more research is needed to better understand these differences and identify appropriate interventions and risk modification.

Treadmill exercise reduces α-synuclein spreading via PPARα

This study underlines the importance of treadmill exercise in reducing α-synuclein (α-syn) spreading in the A53T brain and protecting nigral dopaminergic neurons. Preformed α-syn fibril (PFF) seeding in the internal capsule of young A53T α-syn mice leads to increased spreading of α-syn to substantia nigra and motor cortex and concomitant loss of nigral dopaminergic neurons. However, regular treadmill exercise decreases α-syn spreading in the brain and protects nigral dopaminergic neurons in PFF-seeded mice. Accordingly, treadmill exercise also mitigates α-synucleinopathy in aged A53T mice. While investigating this mechanism, we have observed that treadmill exercise induces the activation of peroxisome proliferator-activated receptor α (PPARα) in the brain to stimulate lysosomal biogenesis via TFEB. Accordingly, treadmill exercise remains unable to stimulate TFEB and reduce α-synucleinopathy in A53T mice lacking PPARα, and fenofibrate, a prototype PPARα agonist, reduces α-synucleinopathy. These results delineate a beneficial function of treadmill exercise in reducing α-syn spreading in the brain via PPARα.

Bioengineered microglia-targeted exosomes facilitate Aβ clearance via enhancing activity of microglial lysosome for promoting cognitive recovery in Alzheimer's disease

Aggregation of amyloid in the form of senile plaques is currently considered to be one of the main mechanisms driving the development of Alzheimer's disease (AD). Therefore, targeting amyloid homeostasis is an important treatment strategy for AD. Microglia, as the main immune cells, contribute to endocytosis and clearance of amyloid beta (Aβ) via lysosome mediated degradation. As abnormal lysosomal function in microglia is associated with inefficient clearance of Aβ in AD, we designed bioengineered microglia-targeting exosomes to promote the targeted delivery of gemfibrozil (Gem) and restore the lysosomal activity of microglia in clearing Aβ aggregation. Our results suggested that mannose-modified exosomes laden with Gem (MExo-Gem) can not only bind with Aβ but also specifically target microglia through the interaction between Exo-delivered mannose and mannose receptors expressed in microglia, thus promoting Aβ entry into microglia. Exosomal Gem activated lysosomal activity and accelerated lysosome-mediated clearance of Aβ in microglia. Finally, MExo-Gem improved the learning and memory ability of AD model mice.

Structural Analysis of Human Serum Albumin in Complex with the Fibrate Drug Gemfibrozil

Gemfibrozil (GEM) is an orally administered lipid-regulating fibrate derivative drug sold under the brand name Lopid^®, among others. Since its approval in the early 80s, GEM has been largely applied to treat hypertriglyceridemia and other disorders of lipid metabolism. Though generally well tolerated, GEM can alter the distribution and the free, active concentration of some co-administered drugs, leading to adverse effects. Most of them appear to be related to the ability of GEM to bind with high affinity human serum albumin (HSA), the major drug-carrier protein in blood plasma. Here, we report the crystal structure of HSA in complex with GEM. Two binding sites have been identified, namely Sudlow’s binding sites I (FA7) and II (FA3–FA4). A comparison of the crystal structure of HSA in complex with GEM with those of other previously described HSA–drug complexes enabled us to appreciate the analogies and differences in their respective binding modes. The elucidation of the molecular interaction between GEM and HSA might offer the basis for the development of novel GEM derivatives that can be safely and synergistically co-administered with other drugs, enabling augmented therapeutic efficacies.

Cooperation of cell adhesion and autophagy in the brain: Functional roles in development and neurodegenerative disease

Cellular adhesive connections directed by the extracellular matrix (ECM) and maintenance of cellular homeostasis by autophagy are seemingly disparate functions that are molecularly intertwined, each regulating the other. This is an emerging field in the brain where the interplay between adhesion and autophagy functions at the intersection of neuroprotection and neurodegeneration. The ECM and adhesion proteins regulate autophagic responses to direct protein clearance and guide regenerative programs that go awry in brain disorders. Concomitantly, autophagic flux acts to regulate adhesion dynamics to mediate neurite outgrowth and synaptic plasticity with functional disruption contributed by neurodegenerative disease. This review highlights the cooperative exchange between cellular adhesion and autophagy in the brain during health and disease. As the mechanistic alliance between adhesion and autophagy has been leveraged therapeutically for metastatic disease, understanding overlapping molecular functions that direct the interplay between adhesion and autophagy might uncover therapeutic strategies to correct or compensate for neurodegeneration.

Revisiting CYP2C9-Mediated drug-drug Interactions: A Review

Drug-drug interactions (DDI) are the most common cases that occur in our healthcare in which are very alarming as it may lead to severe complications. Consumption of natural products concomitantly with conventional drugs or treatment using polypharmacy have become the norm that promoting the potential of pharmacokinetic or pharmacodynamic drug interactions as the combination may mimic, increase or reduce the effects of the drug or the herb which could result in clinically significant interactions. CYP2C9 is the second major isoform from CYP450 family of enzyme, which responsible in phase 1 metabolism of 15-20% clinical drugs. Up to date, many substrates of CYP2C9 have been discovered and these discoveries may open more doors for potential drug-drug interactions in patients. Many studies have been done to evaluate the effect of drugs on the activity of CYP2C9 and how it influenced the effectiveness of therapy in patients. Various data regarding CYP2C9 related DDI from in vitro, in vivo and clinical studies were critically discussed in this review to provide insights on how these drugs and natural products may exhibit drug interactions clinically. This review could be beneficial reference material for health practitioners and researchers.

Visible light-driven conjunctive olefination

Carboxylic acids and aldehydes are ubiquitous in chemistry and are native functionalities in many bioactive molecules and natural products. As such, a general cross-coupling process that involves these partners would open new avenues to achieve molecular diversity. Here we report a visible-light-mediated and transition metal-free conjunctive olefination that uses an alkene 'linchpin' with a defined geometry to cross-couple complex molecular scaffolds that contain carboxylic acids and aldehydes. The chemistry merges two cornerstones of organic synthesis-namely, the Wittig reaction and photoredox catalysis-in a catalytic cycle that couples a radical addition process with the redox generation of a phosphonium ylide. The methodology allows the rapid structural diversification of bioactive molecules and natural products in a native form, with a high functional group tolerance, and also forges a new alkene functional group with a programmable E-Z stereochemistry.

Activation of PPARα enhances astroglial uptake and degradation of β-amyloid

[Figure: see text].

PPARα agonist exerts protective effects in podocyte injury via inhibition of the ANGPTL3 pathway

Peroxisome proliferator-activated receptor α (PPARα) activation has been reported to exert protective effects on podocytes, whereas angiopoietin-like 3 (ANGPTL3) has been shown to exert significant pathogenic effects on these cells. This study aimed to investigate the link between the protective effects of PPARα activation and the pathogenic effects of ANGPTL3 in podocytes. Both PPARα and ANGPTL3 were expressed in cultured podocytes. PPARα mRNA and protein levels decreased whereas ANGPTL3 mRNA and protein levels increased in a time-dependent manner in podocytes treated with puromycin aminonucleoside (PAN). Gemfibrozil, a pharmacological agonist of PPARα, increased PPARα levels and activity in podocytes. The drug also decreased ANGPTL3 levels by potentially weakening ANGPTL3 promoter activity in both normal and PAN-treated podocytes. Furthermore, gemfibrozil significantly decreased PAN-induced apoptosis and F-actin rearrangement. Primary podocytes from Angptl3-knockout mice were cultured. There was no significant difference between Angptl3^-/- podocytes treated with or without gemfibrozil in the lamellipodia numbers after PAN treatment. The results suggested that the protective effects of gemfibrozil on podocytes were not exerted following knockout of the Angptl3 gene. This study identified a novel mechanism of the PPARα agonist gemfibrozil that exerts its protective effects by inhibiting PAN-induced apoptosis and cytoskeleton rearrangements through inhibition of ANGPTL3 expression.

Gemfibrozil Protects Dopaminergic Neurons in a Mouse Model of Parkinson's Disease via PPARα-Dependent Astrocytic GDNF Pathway

Parkinson's disease (PD) is the most common neurodegenerative movement disorder in humans. Despite intense investigations, effective therapies are not yet available to halt the progression of PD. Gemfibrozil, a Food and Drug Administration-approved lipid-lowering drug, is known to decrease the risk of coronary heart disease by increasing the level of high-density lipoprotein cholesterol and decreasing the level of low-density lipoprotein cholesterol. This study underlines the importance of gemfibrozil in protecting dopaminergic neurons in an animal model of PD. Oral administration of the human equivalent dose of gemfibrozil protected tyrosine hydroxylase (TH)-positive dopaminergic neurons in the substantia nigra pars compacta and TH fibers in the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-insulted mice of both sexes. Accordingly, gemfibrozil also normalized striatal neurotransmitters and improved locomotor activities in MPTP-intoxicated mice. Gemfibrozil-mediated protection of the nigrostriatal and locomotor activities in WT but not PPARα-/- mice from MPTP intoxication suggests that gemfibrozil needs the involvement of peroxisome proliferator-activated receptor α (PPARα) in protecting dopaminergic neurons. While investigating further mechanisms, we found that gemfibrozil stimulated the transcription of glial-derived neurotrophic factor (GDNF) gene in astrocytes via PPARα and that gemfibrozil protected nigral neurons, normalized striatal fibers and neurotransmitters, and improved locomotor activities in MPTP-intoxicated Gfafcre mice, but not GdnfΔastro mice lacking GDNF in astrocytes. These findings highlight the importance of the PPARα-dependent astroglial GDNF pathway in gemfibrozil-mediated protection of dopaminergic neurons in an animal model of PD and suggest the possible therapeutic use of gemfibrozil in PD patients.SIGNIFICANCE STATEMENT Increasing the level of glial cell-derived neurotrophic factor (GDNF) in the brain is important for the protection of dopamine neurons in Parkinson's disease (PD). Although gene manipulation and GDNF protein infusion into the brain are available options, it seems from the therapeutic angle that the best option would be to stimulate/induce the production of GDNF in vivo in the brain of PD patients. Here, we delineate that gemfibrozil, a lipid-lowering drug, stimulates GDNF in astrocytes via peroxisome proliferator-activated receptor α (PPARα). Moreover, gemfibrozil protected nigral neurons, normalized striatal fibers and neurotransmitters, and improved locomotor activities from MPTP toxicity via the PPARα-dependent astroglial GDNF pathway. These studies highlight a new property of gemfibrozil and suggest its possible therapeutic use in PD patients.

Metabolism pathways of arachidonic acids: mechanisms and potential therapeutic targets

The arachidonic acid (AA) pathway plays a key role in cardiovascular biology, carcinogenesis, and many inflammatory diseases, such as asthma, arthritis, etc. Esterified AA on the inner surface of the cell membrane is hydrolyzed to its free form by phospholipase A2 (PLA2), which is in turn further metabolized by cyclooxygenases (COXs) and lipoxygenases (LOXs) and cytochrome P450 (CYP) enzymes to a spectrum of bioactive mediators that includes prostanoids, leukotrienes (LTs), epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid (diHETEs), eicosatetraenoic acids (ETEs), and lipoxins (LXs). Many of the latter mediators are considered to be novel preventive and therapeutic targets for cardiovascular diseases (CVD), cancers, and inflammatory diseases. This review sets out to summarize the physiological and pathophysiological importance of the AA metabolizing pathways and outline the molecular mechanisms underlying the actions of AA related to its three main metabolic pathways in CVD and cancer progression will provide valuable insight for developing new therapeutic drugs for CVD and anti-cancer agents such as inhibitors of EETs or 2J2. Thus, we herein present a synopsis of AA metabolism in human health, cardiovascular and cancer biology, and the signaling pathways involved in these processes. To explore the role of the AA metabolism and potential therapies, we also introduce the current newly clinical studies targeting AA metabolisms in the different disease conditions.

Efficacy of Gemfibrozil as an Adjunct to Sertraline in Major Depressive Disorder, A Double-Blind, Randomized, and Placebo-Controlled Clinical Trial

Objective: Major depressive disorder (MDD) is predicted to be one of the biggest disease burden in the future. The antidepressant activity of gemfibrozil has been recently considered. In this study, we assessed the effectiveness of gemfibrozil as a sertraline adjunct in treating patients with MDD.

Method: In this study, 46 patients with MDD based on the DSM-V criteria with a minimum score of 22 on the 17-item Hamilton Rating Scale for Depression (HAM-D) were divided into two groups. One group was treated with 300 mg of gemfibrozil daily and the other group treated with placebo. Each group was treated simultaneously with 100 mg of sertraline daily for 8 weeks. The trial was randomized and double-blind. To assess the response to treatment, patients were evaluated at baseline and then at weeks 2, 4 and 8 using the HAM-D score.

Results: The study was completed by 45 patients up to the final stages and follow-up visits. Repeated measure ANOVA with a Greenhouse-Geisser correction showed a significant difference for time×treatment interaction on within-subjects HAM-D scores [p–value= 0.026]. A notable difference was seen in time [p–value < 0.001]. The test of between-subject effects also represented a remarkable consequence of treatment on HAM-D scores at weeks 2, 4, and 8 [p–value = 0.07]. Using Kaplan-Meier estimate curves, time to remission periods were notable different between the 2 trial groups [Log-Rank p–value = 0.003].

Conclusion: Gemfibrozil is an effective adjunctive treatment in MDD and can be used to reduce depression symptoms.

PPARα Between Aspirin and Plaque Clearance

Mounting evidence has identified that impaired amyloid-β (Aβ) clearance might contribute to Alzheimer's disease (AD) pathology. The lysosome-autophagy network plays an important role in protein homeostasis and cell health by removing abnormal protein aggregates via intracellular degradation. Therefore, stimulation of cellular degradative machinery for efficient removal of Aβ has emerged as a growing field in AD research. However, mechanisms controlling such pathways and drugs to promote such mechanisms are poorly understood. Aspirin is a widely used drug throughout the world and recent studies have identified a new function of this drug. At low doses, aspirin stimulates lysosomal biogenesis and autophagy to clear amyloid plaques in an animal model of AD. This review delineates such functions of aspirin and analyzes underlying mechanisms that involve peroxisome proliferator-activated receptor alpha (PPARα)-mediated transcription of transcription factor EB (TFEB), the master regulator of lysosomal biogenesis.

Peroxisome Proliferator-Activated Receptors and Their Novel Ligands as Candidates for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, frequently associated with obesity and type 2 diabetes. Steatosis is the initial stage of the disease, which is characterized by lipid accumulation in hepatocytes, which can progress to non-alcoholic steatohepatitis (NASH) with inflammation and various levels of fibrosis that further increase the risk of developing cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD is influenced by interactions between genetic and environmental factors and involves several biological processes in multiple organs. No effective therapy is currently available for the treatment of NAFLD. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that regulate many functions that are disturbed in NAFLD, including glucose and lipid metabolism, as well as inflammation. Thus, they represent relevant clinical targets for NAFLD. In this review, we describe the determinants and mechanisms underlying the pathogenesis of NAFLD, its progression and complications, as well as the current therapeutic strategies that are employed. We also focus on the complementary and distinct roles of PPAR isotypes in many biological processes and on the effects of first-generation PPAR agonists. Finally, we review novel and safe PPAR agonists with improved efficacy and their potential use in the treatment of NAFLD.

Effects of gemfibrozil on sex hormones and reproduction related performances of Oryzias latipes following long-term (155 d) and short-term (21 d) exposure

Gemfibrozil, a lipid-regulating pharmaceutical, has been widely used for treating dyslipidemia in humans and detected frequently in freshwater environments. Since plasma cholesterol is a precursor of steroid hormones, the use of gemfibrozil may influence the sex hormone balances. However, its endocrine toxicity following long-term exposure is not well understood. The purpose of the present study is to investigate the effects of gemfibrozil on sex hormones and reproductive outcomes in a freshwater fish, following a long-term (155 d) exposure. For this purpose, Japanese medaka embryos (F0) were exposed to a series of gemfibrozil concentrations, i.e., 0, 0.04, 0.4, 3.7, and 40 mg/L for 155 d, and reproductive parameters, sex hormones, and associated gene expressions were assessed. For comparison, a short-term exposure (21 d) was performed separately with adult medaka and measured for sex hormones and related gene expressions. Following the 155 d long-term exposure, the fecundity showed a decreasing pattern. In addition, at 3.7 mg/L gemfibrozil, testosterone (T) level in the female fish was significantly decreased, and the hatchability of F1 fish was significantly decreased. The estrogen receptor (er) or vitellogenin (vtg) genes in gonads and liver were up-regulated. However, plasma cholesterol levels did not show significant changes in both sexes. The observations from the short-term (21 d) exposure were different from those of the long-term exposure. Following the short-term exposure, decreased 17β-estradiol (E2), and 11-ketotestosterone (11-KT) levels along with decrease plasma cholesterol were observed in the male fish. The hormone disruption following the short-term exposure appears to be associated with the hypocholesterolemic activity of gemfibrozil. Our results show that the mechanisms of gemfibrozil toxicity may depend on the exposure duration. Consequences of long-term exposure to other fibrates in the water environment warrant further investigations.

Activation of Peroxisome Proliferator-Activated Receptor-α Increases the Expression of Nuclear Receptor Related 1 Protein (Nurr1) in Dopaminergic Neurons

Nuclear receptor related 1 protein (Nurr1) is an important transcription factor required for differentiation and maintenance of midbrain dopaminergic (DA) neurons. Since decrease in Nurr1 function either due to diminished expression or rare mutation is associated with Parkinson's disease (PD), upregulation of Nurr1 may be beneficial for PD. However, such mechanisms are poorly understood. This study underlines the importance of peroxisome proliferator-activated receptor (PPAR)α in controlling the transcription of Nurr1. Our mRNA analyses followed by different immunoassays clearly indicated that PPARα agonist gemfibrozil strongly upregulated the expression of Nurr1 in wild-type, but not PPARα^-/-, DA neurons. Moreover, identification of conserved PPRE in the promoter of Nurr1 gene followed by chromatin immunoprecipitation analysis, PPRE luciferase assay, and manipulation of Nurr1 gene by viral transduction of different PPARα plasmids confirmed that PPARα was indeed involved in the expression of Nurr1. Finally, oral administration of gemfibrozil increased Nurr1 expression in vivo in nigra of wild-type, but not PPARα^-/-, mice identifying PPARα as a novel regulator of Nurr1 expression and associated protection of DA neurons.

Gemfibrozil, a Lipid-Lowering Drug, Lowers Amyloid Plaque Pathology and Enhances Memory in a Mouse Model of Alzheimer's Disease via Peroxisome Proliferator-Activated Receptor α

Deposition of extracellular senile plaques containing amyloid-β is one of the major neuropathological characteristics of Alzheimer’s disease (AD). Therefore, targeting amyloid-β dyshomeostasis is an important therapeutic strategy for treatment of AD. In this study, we demonstrate that gemfibrozil, an FDA-approved drug for hyperlipidemia, can lower the amyloid plaque burden in the hippocampus and cortex of the 5XFAD model of AD. Additionally, gemfibrozil reduced microgliosis and astrogliosis associated with plaque in these mice. Administration of gemfibrozil also improved spatial learning and memory of the 5XFAD mice. Finally, we delineate that gemfibrozil requires the transcription factor peroxisome proliferator-activated receptor alpha (PPARα) to exhibit its amyloid lowering and memory enhancing effects in 5XFAD mice. These results highlight a new therapeutic property of gemfibrozil and suggest that this drug may be repurposed for treatment of AD.

Cinnamic Acid Protects the Nigrostriatum in a Mouse Model of Parkinson's Disease via Peroxisome Proliferator-Activated Receptorα

Parkinson's disease (PD) is the second most common devastating human neurodegenerative disorder and despite intense investigation, no effective therapy is available for PD. Cinnamic acid, a naturally occurring aromatic fatty acid of low toxicity, is a precursor for the synthesis of a huge number of plant substances. This study highlights the neuroprotective effect of cinnamic acid in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Oral administration of cinnamic acid protected tyrosine hydroxylase (TH)-positive dopaminergic neurons in the substantia nigra pars compacta (SNpc) and TH fibers in the striatum of MPTP-insulted mice. Accordingly, oral cinnamic acid also normalized striatal neurotransmitters and improved locomotor activities in MPTP-intoxicated mice. While investigating mechanisms, we found that cinnamic acid induced the activation of peroxisome proliferator-activated receptor α (PPARα), but not PPARβ, in primary mouse astrocytes. Cinnamic acid mediated protection of the nigrostriatal system and locomotor activities in WT and PPARβ (-/-), but not PPARα (-/-) mice from MPTP intoxication suggests that cinnamic acid requires the involvement of PPARα in protecting dopaminergic neurons in this model of PD. This study delineates a new function of cinnamic acid in protecting dopaminergic neurons via PPARα that could be beneficial for PD.

Cinnamic acid activates PPARα to stimulate Lysosomal biogenesis and lower Amyloid plaque pathology in an Alzheimer's disease mouse model

The response of the lysosomes, the waste clearance machinery of the cell, to different environmental stimuli is coordinated by a gene network with a master regulator Transcription factor EB (TFEB) at the core. Disruption of multiple facets of the lysosomal and autophagic network has been linked to various neurodegenerative and lysosomal storage disorders, making TFEB an attractive therapeutic target to rescue or augment lysosomal function under pathological scenario. In this study, we demonstrate that cinnamic acid, a naturally occurring plant-based product, induces lysosomal biogenesis in mouse primary brain cells via upregulation of TFEB. We delineate that cinnamic acid activates the nuclear hormone receptor PPARα to transcriptionally upregulate TFEB and stimulate lysosomal biogenesis. Moreover, using in-silico and biochemical approaches we established that cinnamic acid serves as a potent ligand for peroxisome proliferator-activated receptor α (PPARα). Finally, cinnamic acid treatment in male and female 5× Familial Alzheimer’s disease (5XFAD) mice remarkably reduced cerebral amyloid-beta plaque burden and improved memory via PPARα. Therefore, stimulation of lysosomal biogenesis by cinnamic acid may have therapeutic implications for treatment of Alzheimer’s disease and other lysosomal disorders originating from accumulation of toxic protein aggregates.

Risk of Incident Osteoarthritis of the Hand in Statin Initiators: A Sequential Cohort Study

OBJECTIVE

To investigate the association between statin therapy initiation and incident hand osteoarthritis (OA).

METHODS

We performed a propensity score-matched cohort study using data from the UK-based Clinical Practice Research Datalink. Statin initiators had ≥1 statin prescription between 1996 and 2015 and were matched 1:1 on their propensity score to noninitiators within 10 sequential 2-year cohort entry blocks. After a 180-day run-in period, patients were followed in an as-treated approach until a recorded diagnosis of hand OA or until censoring (change in exposure status, development of an exclusion criterion, or maximum follow-up of 5.5 years). We applied Cox proportional hazard regression to calculate hazard ratios (HRs) with 95% confidence intervals (95% CIs) overall and in subgroups of sex, age, statin dose, statin agent, preexisting dyslipidemia, and treatment duration. To compare results, we ran all analyses with negative and positive control outcomes and assessed generalized OA as a secondary outcome. We further performed the overall analysis with an active comparator (topical glaucoma therapy initiators).

RESULTS

Among 233,608 statin initiators and the same number of noninitiators, we observed an overall HR for hand OA of 0.98 (95% CI 0.88-1.09). The observed null result remained unchanged in all subgroups. Results were highly similar for generalized OA and negative control outcomes. In addition, the active comparator analysis showed a null result with an HR for hand OA of 0.85 (95% CI 0.56-1.29). Previously known associations with positive control outcomes were observed.

CONCLUSION

There was no association between statin initiation and incident hand OA in this study.

Effect of gemfibrozil on cardiotoxicity induced by doxorubicin in male experimental rats

Cardiotoxicity is an adverse effect of the anticancer drug doxorubicin (DOX). Gemfibrozil (GEM) is a lipid-lowering drug with a number of biological properties such as anti-inflammatory and antioxidant activities. Therefore, we decided to investigate the effect of GEM on DOX-induced cardiotoxicity in rats. Twenty-eight adult male Wistar rats were divided into four experimental groups as follows: Group I received normal saline (2 ml/kg) orally for 14 days, group II received DOX (2.5 mg/kg; in six injections; accumulative dose: 15 mg/kg) intraperitonially for 14 days, group III received DOX + GEM (100 mg/kg) orally for 14 days concomitantly with DOX administration, and group IV received GEM orally for 14 days. Lipid panel, various biochemical biomarkers, and histological observations were evaluated in serum and heart samples. According to our results, DOX significantly increased the levels of lipid panel (triglycerides, total cholesterol, and low-density lipoproteins cholesterol) as well as markers of cardiac dysfunction (Aspartate aminotransferase, Creatine kinase-muscle/brain, Lactate dehydrogenase and Cardiac Troponin I). Moreover, DOX significantly increased malondialdehyde and nitric oxide levels in cardiac tissue. Furthermore, administration of DOX reduced the level of glutathione as well as the superoxide dismutase, catalase, and Glutathione peroxidase activities. DOX-treated rats showed significantly higher tumor necrosis factor-α and interleukin-1β. GEM administration significantly attenuated the lipid panel and biochemical biomarkers in DOX-treated rats. Our results were confirmed by histopathological evaluations of the heart. Based on our findings, GEM is a promising cardioprotective agent in patients treated with DOX through mitigative effects on biochemical markers and oxidative stress indices.

A multibiomarker approach highlights effects induced by the human pharmaceutical gemfibrozil to gilthead seabream Sparus aurata

Lipid regulators are among the most prescribed human pharmaceuticals worldwide. Gemfibrozil, which belongs to this class of pharmaceuticals, is one of the most frequently encountered in the aquatic environment. However, there is limited information concerning the mechanisms involved in gemfibrozil effects to aquatic organisms, particularly to marine organisms. Based on this knowledge gap, the current study aimed to assess biochemical and behavioral effects following a sublethal exposure to gemfibrozil (1.5, 15, 150, 1500 and 15,000 μg L^-1) in the estuarine/marine fish Sparus aurata. After the exposure to 1.5 μg L^-1 of gemfibrozil, fish had reduced ability to swim against a water flow and increased lipid peroxidation in the liver. At concentrations between 15-15,000 μg L^-1, the activities of some enzymes involved in antioxidant defense were induced, appearing to be sufficient to prevent oxidative damage. Depending on the organ, different responses to gemfibrozil were displayed, with enzymes like catalase being more stimulated in gills, whereas glutathione peroxidase was more activated in liver. Although there were no obvious concentration-response relationships, the integrated biomarker response version 2 (IBRv2) analysis revealed that the highest concentrations of gemfibrozil (between 150-15,000 μg L^-1) caused more alterations. All the tested concentrations of gemfibrozil induced effects in S. aurata, in terms of behavior and/or oxidative stress responses. Oxidative damage was found at a concentration that is considered environmentally relevant, suggesting a potential of this pharmaceutical to impact fish populations.

Protective Effect of Gemfibrozil on Hepatotoxicity Induced by Acetaminophen in Mice: the Importance of Oxidative Stress Suppression

Purpose: Gemfibrozil (GEM) apart from agonist activity at peroxisome proliferator-activated receptor-alpha (PPAR-α) has antioxidant and anti-inflammatory properties. Accordingly, the present study was designed to investigate the protective effect of GEM on acute liver toxicity induced by acetaminophen (APAP) in mice.

Methods: In this study, mice divided in seven groups include, control group, APAP group, GEM group, three APAP groups pretreated with GEM at the doses of 25, 50 and 100 mg/kg respectively and APAP group pretreated with N-Acetyl cysteine. GEM, NAC or vehicle were administered for 10 days. In last day, GEM and NAC were gavaged 1 h before and 1 h after APAP injection. Twenty four hours after APAP, mice were sacrificed. Serum parameters include alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver tissue markers including catalase enzyme activity, reactive oxygen species (ROS), malondialdehyde and reduced glutathione (GSH) levels determined and histopathological parameters measured.

Results: GEM led to significant decrease in serum ALT and AST activities and increase in catalase activity and hepatic GSH level and reduces malondialdehyde and ROS levels in the liver tissue. In confirmation, histopathological findings revealed that GEM decrease degeneration, vacuolation and necrosis of hepatocytes and infiltration of inflammatory cells.

Conclusion: Present data demonstrated that GEM has antioxidant properties and can protect the liver from APAP toxicity, just in the same pathway that toxicity occurs by toxic ROS and that GEM may be an alternative therapeutic agent to NAC in APAP toxicity.

The effects of parental carbamazepine and gemfibrozil exposure on sexual differentiation in zebrafish (Danio rerio)

The effects of parental exposure to pharmaceuticals on sexual differentiation in F1 offspring were examined in zebrafish (Danio rerio). Adult zebrafish were exposed to 0 or 10 μg/L of carbamazepine or gemfibrozil for 6 wk and bred in pairwise crosses to generate 7 distinct lineages. Lineages were formed with both parents from the same treatment group or with only one parent exposed, to delineate between maternal and paternal effects. The F1 offspring from each lineage were reared in clean water and sampled at 45 and 60 d post fertilization (dpf). Gonadal differentiation was assessed by histology. The morphological stages of the gonads were converted to a quantitative day-equivalent based on data from offspring of untreated parents sampled from 15 to 75 dpf, which enabled a quantitative statistical analysis on the timing of sexual differentiation. Paternal, but not maternal, exposure to carbamazepine resulted in significantly faster sexual differentiation and a male-biased sex ratio; these effects were not observed when both parents were exposed. Combined paternal and maternal exposure to gemfibrozil resulted in significantly faster sexual differentiation, and paternal, but not maternal, exposure to gemfibrozil led to male-biased sex ratios. The present study demonstrates the ability of parental exposure to pharmaceuticals to disrupt sexual differentiation in the F1 offspring and also shows that effects may be uniquely influenced by which parent was exposed. Environ Toxicol Chem 2018;37:1696-1706. © 2018 SETAC.

Stochastic Pharmacokinetic-Pharmacodynamic Modeling for Assessing the Systemic Health Risk of Perfluorooctanoate (PFOA)

A phase 1 dose-escalation trial assessed the chemotherapeutic potential of ammonium perfluorooctanoate (APFO). Forty-nine primarily solid-tumor cancer patients who failed standard therapy received weekly APFO doses (50-1200 mg) for 6 weeks. Clinical chemistries and plasma PFOA (anionic APFO) were measured predose and weekly thereafter. Several clinical measures including total cholesterol, high-density lipoproteins (HDLs), thyroid stimulating hormone (TSH), and free thyroxine (fT4), relative to PFOA concentrations were examined by: Standard statistical analyses using generalized estimating equations (GEE) and a probabilistic analysis using probability distribution functions (pdf) at various PFOA concentrations; and a 2-compartment pharmacokinetic/pharmacodynamic (PK/PD) model to directly estimate mean changes. Based on the GEE, the average rates of change in total cholesterol and fT4 associated with increasing PFOA were approximately -1.2×10-3 mmol/l/μM and 2.8×10-3 pmol/l/μM, respectively. The PK/PD model predicted more closely the trends observed in the data as well as the pdfs of biomarkers. A decline in total cholesterol was observed, with a clear transition in shape and range of the pdfs, manifested by the maximum value of the Kullback-Leibler (KL) divergence, that occurred at plasma PFOA between 420 and 565 μM (175 000-230 000 ng/ml). High-density lipoprotein was unchanged. An increase in fT4 was observed at a higher PFOA transition point, albeit TSH was unchanged. Our findings are consistent with some animal models and may motivate re-examination of the epidemiologic studies to PFOA at levels several orders of magnitude lower than this study. These observational studies have reported contrary associations, but currently understood biology does not support the existence of such conflicting effects.

Gemfibrozil and carbamazepine decrease steroid production in zebrafish testes (Danio rerio)

Gemfibrozil (GEM) and carbamazepine (CBZ) are two environmentally relevant pharmaceuticals and chronic exposure of fish to these compounds has decreased androgen levels and fish reproduction in laboratory studies. The main focus of this study was to examine the effects of GEM and CBZ on testicular steroid production, using zebrafish as a model species. Chronic water borne exposures of adult zebrafish to 10 μg/L of GEM and CBZ were conducted and the dosing was confirmed by chemical analysis of water as 17.5 ± 1.78 and 11.2 ± 1.08 μg/L respectively. A 67 day exposure led to reduced reproductive output and lowered whole body, plasma, and testicular 11-ketotestosterone (11-KT). Testicular production of 11-KT was examined post exposure (42 days) using ex vivo cultures to determine basal and stimulated steroid production. The goal was to ascertain the step impaired in the steroidogenic pathway by each compound. Ex vivo 11-KT production in testes from males chronically exposed to GEM and CBZ was lower than that from unexposed males. Although hCG, 25-OH cholesterol, and pregnenolone stimulation increased 11-KT production in all treatment groups over basal levels, hCG stimulated 11-KT production remained significantly less in testes from exposed males compared to controls. 25-OH cholesterol and pregnenolone stimulated 11-KT production was similar between GEM and control groups but the CBZ group had lower 11-KT production than controls with both stimulants. We therefore propose that chronic GEM and CBZ exposure can reduce production of 11-KT in testes through direct effects independent of mediation through HPG axis. The biochemical processes for steroid production appear un-impacted by GEM exposure; while CBZ exposure may influence steroidogenic enzyme expression or function.

Pigments from Filamentous Ascomycetes for Combination Therapy

Filamentous ascomycetes (Neurospora and Monascus) have been studied for a long time because of their production of secondary metabolites such as microbial pigments. The ascomycetes represent an interesting group of compounds with high potential for medicinal applications. Many recent studies have shown their efficacy in the treatment of serious pathological states such as oncological diseases, neurodegenerative diseases and hyperlipidaemia. Nevertheless, the clinical usability of ascomycetes is still limited. However, this problem can be solved by the use of these compounds with combinations of other therapeutic agents. This strategy can suppress their side effects and improve their therapeutic efficacy. Moreover, their co-application can significantly enhance conventional therapies that are used. This review summarizes and discusses the general principles of this approach, introduced and supported by numerous examples. In addition, the prediction of the future potential application of this methodology is included.

Cholesterol is required for stability and infectivity of influenza A and respiratory syncytial viruses

Cholesterol-rich lipid raft microdomains in the plasma membrane are considered to play a major role in the enveloped virus lifecycle. However, the functional role of cholesterol in assembly, infectivity and stability of respiratory RNA viruses is not fully understood. We previously reported that depletion of cellular cholesterol by cholesterol-reducing agents decreased production of human parainfluenza virus type 1 (hPIV1) particles by inhibiting virus assembly. In this study, we analyzed the role of cholesterol on influenza A virus (IAV) and respiratory syncytial virus (RSV) production. Unlike hPIV1, treatment of human airway cells with the agents did not decrease virus particle production. However, the released virions were less homogeneous in density and unstable. Addition of exogenous cholesterol to the released virions restored virus stability and infectivity. Collectively, these data indicate a critical role of cholesterol in maintaining IAV and RSV membrane structure that is essential for sustaining viral stability and infectivity.

Master Autophagy Regulator Transcription Factor EB Regulates Cigarette Smoke-Induced Autophagy Impairment and Chronic Obstructive Pulmonary Disease-Emphysema Pathogenesis

AIMS

Recent studies have shown that cigarette smoke (CS)-induced oxidative stress impairs autophagy, resulting in aggresome-formation that correlates with severity of chronic obstructive pulmonary disease (COPD)-emphysema, although the specific step in autophagy pathway that is impaired is unknown. Hence, in this study, we aimed to evaluate the role of master autophagy transcription factor EB (TFEB) in CS-induced COPD-emphysema pathogenesis.

RESULTS

We first observed that TFEB accumulates in perinuclear spaces as aggresome-bodies in COPD lung tissues of tobacco smokers and severe emphysema subjects, compared with non-emphysema or nonsmoker controls. Next, Beas2b cells and C57BL/6 mice were exposed to either cigarette smoke extract (CSE) or subchronic-CS (sc-CS), followed by treatment with potent TFEB-inducing drug, gemfibrozil (GEM, or fisetin as an alternate), to experimentally verify the role of TFEB in COPD. Our in vitro results indicate that GEM/fisetin-mediated TFEB induction significantly (p < 0.05) decreases CSE-induced autophagy-impairment (Ub/LC3B reporter and autophagy flux assay) and resulting aggresome-formation (Ub/p62 coexpression/accumulation; immunoblotting and staining) by controlling reactive oxygen species (ROS) activity. Intriguingly, we observed that CS induces TFEB accumulation in the insoluble protein fractions of Beas2b cells, which shows a partial rescue with GEM treatment. Moreover, TFEB knockdown induces oxidative stress, autophagy-impairment, and senescence, which can all be mitigated by GEM-mediated TFEB induction. Finally, in vivo studies were used to verify that CS-induced autophagy-impairment (increased Ub, p62, and valosin-containing protein in the insoluble protein fractions of lung/cell lysates), inflammation (interleukin-6 [IL-6] levels in bronchoalveolar lavage fluid and iNOS expression in lung sections), apoptosis (caspase-3/7), and resulting emphysema (hematoxylin and eosin [H&E]) can be controlled by GEM-mediated TFEB induction (p < 0.05).

INNOVATION

CS exposure impairs autophagy in COPD-emphysema by inducing perinuclear localization of master autophagy regulator, TFEB, to aggresome-bodies.

CONCLUSION

TFEB-inducing drug(s) can control CS-induced TFEB/autophagy-impairment and COPD-emphysema pathogenesis. Antioxid. Redox Signal. 27, 150-167.

Safety and potential efficacy of gemfibrozil as a supportive treatment for children with late infantile neuronal ceroid lipofuscinosis and other lipid storage disorders

Neuronal Ceroid Lipofuscinosis (NCL), also known as Batten disease, is a group of genetically distinct lysosomal disorders that mainly affect the central nervous system, resulting in progressive motor and cognitive decline primarily in children. Multiple distinct genes involved in the metabolism of lipids have been identified to date with various mutations in this family of diseases. There is no cure for these diseases but some new therapeutic approaches have been tested that offer more hope than the standard palliative care. Many of the therapeutic advances require invasive procedures but some progress in slowing the disease has been found and more options can be expected in the future. We also review the literature on children with disease/conditions other than NCL for the non-invasive use, safety, and tolerability of a lipid-lowering drug, gemfibrozil, as a potential treatment for NCLs. Gemfibrozil has shown efficacy in an animal model of NCL known as CLN2 (late infantile classic juvenile) and has been shown to be safe for lowering lipids in children. Among the 200 non-NCL children found in the published literature who were treated with gemfibrozil for NCL-related problems, only 3 experienced adverse events, including 2 with muscle pain and 1 with localized linear IgA bullous dermatitis. We conclude that gemfibrozil is safe for long-term use in children, causes minimal adverse events, is well tolerated, and may delay the progression of NCLs. Gemfibrozil may potentially be an alternative to more invasive therapeutic approaches currently under investigation and has the potential to be used in combination with other therapeutic approaches.

Gemfibrozil, food and drug administration-approved lipid-lowering drug, increases longevity in mouse model of late infantile neuronal ceroid lipofuscinosis

Late Infantile Neuronal Ceroid Lipofuscinosis (LINCL) is a rare neurodegenerative disease caused by mutations in the Cln2 gene that leads to deficiency or loss of function of the tripeptidyl peptidase 1 (TPP1) enzyme. TPP1 deficiency is known to cause the accumulation of autofluoroscent lipid-protein pigments in brain. Similar to other neurodegenerative disorders, LINCL is also associated with neuroinflammation and neuronal damage. Despite investigations, no effective therapy is currently available for LINCL. Therefore, we administered gemfibrozil (gem), an food and drug administration (FDA)-approved lipid-lowering drug, which has been shown to stimulate lysosomal biogenesis and induce anti-inflammation, orally, at a dose of 7.5 mg/kg body wt/day to Cln2^(-/-) mice. We observed that gem-fed Cln2^(-/-) mice lived longer by more than 10 weeks and had better motor activity compared to vehicle (0.1% Methyl cellulose) treatment. Gem treatment lowered the burden of storage materials, increased anti-inflammatory factors like SOCS3 and IL-1Ra, up-regulated anti-apoptotic molecule like phospho-Bad, and reduced neuronal apoptosis in the brain of Cln2^(-/-) mice. Collectively, this study reinforces a neuroprotective role of gem that may be of therapeutic interest in improving the quality of life in LINCL patients.

Cholesterol reducing agents inhibit assembly of type I parainfluenza viruses

Many enveloped RNA viruses utilize lipid rafts for the assembly of progeny virions, but the role of cholesterol, a major component of rafts, on paramyxovirus budding and virion formation is controversial. In this study, we analyzed the effects of FDA-approved cholesterol-reducing agents, gemfibrozil and lovastatin, on raft formation and assembly of human parainfluenza virus type 1 (hPIV1) and Sendai virus (SeV). Treatment of the human airway epithelial A549 cells with the agents, especially when combined, significantly decreased production of infectious hPIV1 and SeV. Mechanistic analysis indicated that depletion of cellular cholesterol reduced cell surface accumulation of envelope glycoproteins and association of viral matrix and nucleocapsids with raft membrane, which resulted in impaired virus budding and release from the cells. These results indicate that cellular cholesterol is required for assembly and formation of type 1 parainfluenza viruses and suggest that cholesterol could be an attractive target for antiviral agents against hPIV1.

Fish connectivity mapping: linking chemical stressors by their mechanisms of action-driven transcriptomic profiles

Background

A very large and rapidly growing collection of transcriptomic profiles in public repositories is potentially of great value to developing data-driven bioinformatics applications for toxicology/ecotoxicology. Modeled on human connectivity mapping (Cmap) in biomedical research, this study was undertaken to investigate the utility of an analogous Cmap approach in ecotoxicology. Over 3500 zebrafish (Danio rerio) and fathead minnow (Pimephales promelas) transcriptomic profiles, each associated with one of several dozen chemical treatment conditions, were compiled into three distinct collections of rank-ordered gene lists (ROGLs) by species and microarray platforms. Individual query signatures, each consisting of multiple gene probes differentially expressed in a chemical condition, were used to interrogate the reference ROGLs.

Results

Informative connections were established at high success rates within species when, as defined by their mechanisms of action (MOAs), both query signatures and ROGLs were associated with the same or similar chemicals. Thus, a simple query signature functioned effectively as an exposure biomarker without need for a time-consuming process of development and validation. More importantly, a large reference database of ROGLs also enabled a query signature to cross-interrogate other chemical conditions with overlapping MOAs, leading to novel groupings and subgroupings of seemingly unrelated chemicals at a finer resolution. This approach confirmed the identities of several estrogenic chemicals, as well as a polycyclic aromatic hydrocarbon and a neuro-toxin, in the largely uncharacterized water samples near several waste water treatment plants, and thus demonstrates its future potential utility in real world applications.

Conclusions

The power of Cmap should grow as chemical coverages of ROGLs increase, making it a framework easily scalable in the future. The feasibility of toxicity extrapolation across fish species using Cmap needs more study, however, as more gene expression profiles linked to chemical conditions common to multiple fish species are needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-2406-y) contains supplementary material, which is available to authorized users.

PPARα in lysosomal biogenesis: A perspective

Lysosomes are membrane-bound vesicles containing hydrolytic enzymes, ubiquitously present in all eukaryotic cells. Classically considered to be central to the cellular waste management machinery, recent studies revealed the role of lysosomes in a wide array of cellular processes like, degradation, cellular development, programmed cell death, secretion, plasma membrane repair, nutritional responses, and lipid metabolism. We recently studied the regulation of TFEB, considered to be the master regulator of lysosomal biogenesis, by activation of peroxisomal proliferator activated receptor α (PPARα), one of the key regulators of lipid metabolism. In this article, we discuss how the recent finding could be put in to perspective with the previous findings that relate lysosomal biogenesis to lipid metabolism, and comment on the possibility of a bi-directional interplay between these two distinct cellular processes upon activation of PPARα.

Activation of peroxisome proliferator-activated receptor α induces lysosomal biogenesis in brain cells: implications for lysosomal storage disorders

Lysosomes are ubiquitous membrane-enclosed organelles filled with an acidic interior and are central to the autophagic, endocytic, or phagocytic pathway. In contrast to its classical function as the waste management machinery, lysosomes are now considered to be an integral part of various cellular signaling processes. The diverse functionality of this single organelle requires a very complex and coordinated regulation of its activity with transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, at its core. However, mechanisms by which TFEB is regulated are poorly understood. This study demonstrates that gemfibrozil, an agonist of peroxisome proliferator-activated receptor (PPAR) α, alone and in conjunction with all-trans-retinoic acid is capable of enhancing TFEB in brain cells. We also observed that PPARα, but not PPARβ and PPARγ, is involved in gemfibrozil-mediated up-regulation of TFEB. Reporter assay and chromatin immunoprecipitation studies confirmed the recruitment of retinoid X receptor α, PPARα, and PGC1α on the PPAR-binding site on the Tfeb promoter as well. Subsequently, the drug-mediated induction of TFEB caused an increase in lysosomal protein and the lysosomal abundance in cell. Collectively, this study reinforces the link between lysosomal biogenesis and lipid metabolism with TFEB at the crossroads. Furthermore, gemfibrozil may be of therapeutic value in the treatment of lysosomal storage disorders in which autophagy-lysosome pathway plays an important role.