Brain Mitochondria as a Therapeutic Target for Carnosic Acid.

Carnosic acid (CA), a diterpene obtained mainly from Rosmarinus officinalis and Salvia officinalis, exerts antioxidant, anti-inflammatory, and anti-apoptotic effects in mammalian cells. At least in part, those benefits are associated with the ability that CA modulates mitochondrial physiology. CA attenuated bioenergetics collapse and redox impairments in the mitochondria obtained from brain cells exposed to several toxicants in both in vitro and in vivo experimental models. CA is a potent inducer of the major modulator of the redox biology in animal cells, the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), which controls the expression of a myriad of genes whose products are involved with cytoprotection in different contexts. Moreover, CA upregulates signaling pathways related to the degradation of damaged mitochondria (mitophagy) and with the synthesis of these organelles (mitochondrial biogenesis). Thus, CA may be considered an agent that induces mitochondrial renewal, depending on the circumstances. In this review, we discuss about the mechanisms of action by which CA promotes mitochondrial protection in brain cells.

The C-glucosyl flavone isoorientin pretreatment attenuates the methylglyoxal-induced mitochondrial dysfunction in the human neuroblastoma SH-SY5Y cells: role for the AMPK-PI3K/Akt/Nrf2/γ-GCL/GSH axis.

The reactive dicarbonyl methylglyoxal (MG) behaves as a pro-oxidant agent, causing redox dysfunction and cell death by different mechanisms in mammalian cells. MG is also a mitochondrial toxicant, impairing the oxidative phosphorylation (OXPHOS) system and leading to bioenergetics and redox collapses. MG induces glycation and exerts an important role in neurodegenerative and cardiovascular diseases. Isoorientin (ISO), a C-glucosyl flavone found in Aspalathus linearis, Fagopyrum esculentum, and Passiflora edulis, among others, is an antioxidant and anti-inflammatory molecule. ISO is a potent inducer of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), the master modulator of the redox environment in mammals. We investigated here whether ISO would prevent the mitochondria-related redox and bioenergetics impairments induced by MG in the human neuroblastoma SH-SY5Y cells. The cells were administrated with ISO at 20 µM for 18 h prior to the exposure to MG at 500 µM for further 24 h. It was observed that ISO efficiently prevented the mitochondrial impairments caused by MG. ISO upregulated the activity of the enzyme γ-glutamate-cysteine ligase (γ-GCL), consequently stimulating the synthesis of glutathione (GSH). The inhibition of γ-GCL, adenosine monophosphate-activated protein kinase (AMPK), and phosphoinositide 3-kinase/Akt (PI3K/Akt) suppressed the beneficial effects induced by ISO on the MG-challenged cells. Moreover, silencing of Nrf2 blocked the ISO-dependent γ-GCL and GSH upregulation and the effects on the mitochondria of the MG-challenged cells. Then, ISO caused mitochondrial protection by an AMPK-PI3K/Akt/Nrf2/γ-GCL/GSH-dependent manner in MG-administrated SH-SY5Y cells.

The isothiocyanate sulforaphane prevents mitochondrial impairment and neuroinflammation in the human dopaminergic SH-SY5Y and in the mouse microglial BV2 cells: role for heme oxygenase-1.

Sulforaphane (SFN) promotes protective effects in different cell types. Nonetheless, it remains to be clarified by which mechanism SFN exerts benefits in mammalian cells. Mitochondria are a major source of adenosine triphosphate (ATP) and reactive species in nucleated cells. Mitochondrial impairment result in cellular redox biology disruption, bioenergetic status collapse, and inflammation. Evidence suggest that mitochondrial dysfunction plays a role in neurological disorders. Since a cure was not discovered yet to some of these diseases, investigating strategies to promote mitochondrial protection is pharmacologically relevant and may improve life quality of patients suffering from these maladies. Natural molecules, such as SFN, are potent inducers of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) and, consequently, stimulate the expression of genes whose products, such as heme oxygenase-1 (HO-1), induce cytoprotective actions in mammalian tissues. In this work, we investigated whether SFN (5 µM) would be capable to prevent the dysfunctions caused by chlorpyrifos (CPF) on the human dopaminergic SH-SY5Y cells. Moreover, we examined the effects of a pretreatment with SFN at the same concentration on the mouse microglial BV2 cells stimulated by lipopolysaccharide (LPS) in an experimental model of neuroinflammation. SFN prevented the mitochondrial impairment and the neuroinflammation caused by the chemical stressors in both cell types. Inhibition of heme oxygenase-1 (HO-1) suppressed the mitochondrial protection and anti-inflammatory action afforded by SFN in this experimental model. Overall, SFN promoted cytoprotection by a mechanism dependent on the HO-1 enzyme in the SH-SY5Y and BV2 cells.

Sesamol prevents mitochondrial impairment and pro-inflammatory alterations in the human neuroblastoma SH-SY5Y cells: role for Nrf2.

Mitochondria are a primary source and a target of reactive oxygen species (ROS). Increased mitochondrial production of ROS is associated with bioenergetics decline, cell death, and inflammation. Here we investigated whether a pretreatment (for 24 h) with sesamol (SES; at 12.5-50 µM) would be efficient in preventing the mitochondrial collapse induced by hydrogen peroxide (H2O2, at 300 µM) in the human neuroblastoma SH-SY5Y cell line. We have found that a pretreatment with SES at 25 µM decreased the effects of H2O2 on lipid peroxidation, protein carbonylation, and protein nitration in membranes obtained from the mitochondria isolated from the SH-SY5Y cells. In this regard, SES pretreatment decreased the production of superoxide anion radical (O2-•) by the mitochondria of H2O2-treated cells. SES also prevented the mitochondrial dysfunction induced by H2O2, as assessed by analyzing the activity of the complexes I and V. The H2O2-induced reduction in the production of adenosine triphosphate (ATP) was also prevented by SES. The levels of the pro-inflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), as well as the activity of the transcription factor nuclear factor-κB (NF-κB) were downregulated by the SES pretreatment in the H2O2-challenged cells. Silencing of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor abolished the protection induced by SES regarding mitochondrial function and inflammation. Thus, SES depends on Nrf2 to promote mitochondrial protection in cells facing redox impairment.

Mitochondrial Protection and Anti-inflammatory Effects Induced by Emodin in the Human Neuroblastoma SH-SY5Y Cells Exposed to Hydrogen Peroxide: Involvement of the AMPK/Nrf2 Signaling Pathway.

Emodin (EM; 1,3,8-trihydroxy-6-methylanthracene-9,10-dione; C15H10O5) is an anthraquinone and exerts cytoprotective effects, as observed in both in vitro and in vivo experimental models. Mitochondrial dysfunction induced by reactive species plays a central role in the onset and progression of different human diseases. Thus, we have tested here whether a pretreatment (for 4 h) with EM (at 40 µM) would be able to promote mitochondrial protection in the human neuroblastoma SH-SY5Y cells exposed to the pro-oxidant agent hydrogen peroxide (H2O2). We found that the pretreatment with EM suppressed the effects of H2O2 on the activity of the mitochondrial complexes I and V, as well as on the production of adenosine triphosphate (ATP) and on the mitochondrial membrane potential (MMP). EM also prevented the H2O2-induced collapse in the tricarboxylic acid cycle (TCA) function. An anti-inflammatory role for EM was also observed in this experimental model, since this anthraquinone decreased the secretion of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) by the H2O2-challenged cells. Inhibition of the adenosine monophosphate-activated protein kinase (AMPK) or silencing of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) abolished the protection induced by EM in the H2O2-treated cells. Therefore, EM prevented the H2O2-induced mitochondrial dysfunction and pro-inflammatory state in the SH-SY5Y cells by an AMPK/Nrf2-dependent manner.

The Isothiocyanate Sulforaphane Depends on the Nrf2/γ-GCL/GSH Axis to Prevent Mitochondrial Dysfunction in Cells Exposed to Methylglyoxal.

Methylglyoxal (MG) is a reactive dicarbonyl presenting both endogenous (e.g. glycolysis) and exogenous (e.g. food cooking) sources. MG induces neurotoxicity, at least in part, by affecting mitochondrial function, including a decline in the oxidative phosphorylation (OXPHOS) system activity, bioenergetics failure, and redox disturbances. Sulforaphane (SFN) is an isothiocyanate found mainly in cruciferous vegetables and exerts antioxidant and anti-inflammatory effects in mammalian cells. SFN also decreases mitochondrial vulnerability to several chemical stressors. SFN is a potent activator of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), which is a master regulator of the mammalian redox biology. Here, we have investigated whether and how SFN would be able to prevent the MG-induced mitochondrial collapse in the human neuroblastoma SH-SY5Y cells. The cells were exposed to SFN at 5 µM for 24 h prior to the administration of MG at 500 µM for additional 24 h. We found that SFN prevented the MG-induced OXPHOS dysfunction and mitochondrial redox impairment. SFN stimulated the activity of the enzyme γ-glutamylcysteine ligase (γ-GCL), leading to increased synthesis of glutathione (GSH). Inhibition of γ-GCL with buthionine sulfoximine (BSO) or silencing of Nrf2 using small interfering RNA (siRNA) against this transcription factor reduced the levels of GSH and abolished the mitochondrial protection promoted by SFN in the MG-treated cells. Thus, SFN protected mitochondria of the MG-challenged cells by a mechanism involving the Nrf2/γ-GCL/GSH axis.

Carnosic acid depends on glutathione to promote mitochondrial protection in methylglyoxal-exposed SH-SY5Y cells.

Methylglyoxal (MG) is an endogenously produced toxicant that induces mitochondrial dysfunction leading to impaired redox biology homeostasis, bioenergetics collapse, and cell death in mammalian cells. However, MG toxicity is particularly relevant to neurons and glia given their chemical and metabolic characteristics. Here, we have investigated whether a pretreatment with carnosic acid (CA) would be able to promote mitochondrial protection in human neuroblastoma SH-SY5Y cells exposed to MG. We found that a pretreatment with CA at 1 µM for 12 h prevented the MG-induced lipid peroxidation and protein carbonylation and nitration in the membranes of mitochondria obtained from the SH-SY5Y cells. CA also prevented the MG-elicited Complexes I and V dysfunction, adenosine triphosphate (ATP) levels decline, and loss of mitochondrial membrane potential (MMP). Moreover, CA also reduced the mitochondrial production of the radical anion superoxide (O2-•) in the MG-challenged cells. We found that CA upregulated the synthesis of glutathione (GSH) by increasing the activity of the γ-glutamylcysteine ligase (γ-GCL). Inhibition of the GSH synthesis by buthionine sulfoximine (BSO) abolished the CA-induced mitochondrial protection. Besides, inhibition of the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, as well as silencing of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), suppressed the CA-stimulated protection and the synthesis of GSH. Thus, CA promoted mitochondrial protection by a PI3K/Akt/Nrf2/γ-GCL/GSH axis in MG-treated SH-SY5Y cells.

Pinocembrin pretreatment counteracts the chlorpyrifos-induced HO-1 downregulation, mitochondrial dysfunction, and inflammation in the SH-SY5Y cells.

Chlorpyrifos (CPF), an insecticide, induces pro-oxidant, pro-inflammatory, and pro-apoptotic effects in animal cells. Contamination with CPF occurs not only in farms, since CPF is found in the food consumed in homes. Recently, it was demonstrated that CPF affects the mitochondria, inhibiting components of the electron transfer chain (ETC), causing loss of mitochondrial membrane potential (MMP), and reducing the synthesis of adenosine triphosphate (ATP) by the Complex V. Pinocembrin (PB) is found in propolis and exhibits antioxidant, anti-inflammatory, and anti-apoptotic effects in mammalian cells. PB is a potent inducer of the nuclear factor erythroid 2-related factor 2 (Nrf2), which is a major transcription factor controlling the expression of heme oxygease-1 (HO-1), among others. In the present work, we investigated whether PB would be able to prevent the mitochondrial and immune dysfunctions in the human neuroblastoma SH-SY5Y cells exposed to CPF. PB was tested at 1-25 µM for 4 h before the administration of CPF at 100 µM for additional 24 h. We found that PB prevented the CPF-induced inhibition of ETC, loss of MMP, and decline in the ATP synthesis. PB also promoted anti-inflammatory actions in this experimental model. Silencing of Nrf2 or inhibition of HO-1 suppressed the PB-induced effects in the CPF-challenged cells. Thus, PB promoted beneficial effects by a mechanism dependent on the Nrf2/HO-1/CO + BR axis in the CPF-treated cells.

Carvacrol Depends on Heme Oxygenase-1 (HO-1) to Exert Antioxidant, Anti-inflammatory, and Mitochondria-Related Protection in the Human Neuroblastoma SH-SY5Y Cells Line Exposed to Hydrogen Peroxide.

The link between mitochondrial dysfunction, redox impairment, and inflammation leads to increased rates of brain cells loss in neurodegenerative diseases and in affective disorders. Carvacrol (CAR) is a component of essential oils found in Labiatae. CAR exerts antioxidant and anti-inflammatory effects in different cell types, as assessed in both in vitro and in vivo experimental designs. Nonetheless, it was not previously investigated whether and how CAR would prevent mitochondrial impairment in human cells exposed to a pro-oxidant challenge. Therefore, we analyzed here whether a pretreatment (for 4 h) with CAR (10-1000 µM) would promote mitochondrial protection in the human neuroblastoma cells SH-SY5Y exposed to hydrogen peroxide (H2O2). We found that CAR at 100 µM prevented the H2O2-induced decline in the activity of the complexes I and V, as well as on the levels of adenosine triphosphate (ATP). CAR also prevented the H2O2-elicited decrease in the activity of the mitochondrial enzymes aconitase, α-ketoglutarate dehydrogenase, and succinate dehydrogenase. Moreover, CAR induced an antioxidant action by decreasing the levels of lipid peroxidation, protein carbonylation, and protein nitration in the mitochondrial membranes. Interestingly, CAR prevented the pro-inflammatory action of H2O2 by downregulating the transcription factor nuclear factor-κB (NF-κB). The inhibition of the heme oxygenase-1 (HO-1) enzyme by zinc protoporphyrin IX (ZnPP IX, 10 µM) suppressed the preventive effects caused by CAR regarding mitochondrial function and inflammation. Thus, it is suggested that CAR caused cytoprotective effects by an HO-1-dependent manner in SH-SY5Y cells exposed to H2O2.

Targeting STATs in neuroinflammation: The road less traveled!

JAK/STAT transduction pathway is a highly conserved pathway implicated in regulating cellular proliferation, differentiation, survival and apoptosis. Dysregulation of this pathway is involved in the onset of autoimmune, haematological, oncological, metabolic and neurological diseases. Over the last few years, the research of anti-neuroinflammatory agents has gained considerable attention. The ability to diminish the STAT-induced transcription of inflammatory genes is documented for both natural compounds (such as polyphenols) and chemical drugs. Among polyphenols, quercetin and curcumin directly inhibit STAT, while Berberis vulgaris L. and Sophora alopecuroides L extracts act indirectly. Also, the Food and Drug Administration has approved several JAK/STAT inhibitors (direct or indirect) for treating inflammatory diseases, indicating STAT can be considered as a therapeutic target for neuroinflammatory pathologies. Considering the encouraging data obtained so far, clinical trials are warranted to demonstrate the effectiveness and potential use in the clinical practice of STAT inhibitors to treat inflammation-associated neurodegenerative pathologies.

Naringenin Exerts Anti-inflammatory Effects in Paraquat-Treated SH-SY5Y Cells Through a Mechanism Associated with the Nrf2/HO-1 Axis.

Naringenin (NGN; 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one; C15H12O5), a flavanone, is found in citrus fruits and has been viewed as an antioxidant and anti-inflammatory agent. NGN is a potent inducer of the nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulates the expression of heme oxygenase-1 (HO-1), an enzyme exhibiting both antioxidant and anti-inflammatory effects. The complete mechanism by which NGN exerts anti-inflammatory actions is not completely understood yet. Therefore, we investigated here whether NGN would be able to reduce the inflammation induced by paraquat (PQ) in SH-SY5Y cells. Additionally, we analyzed the mechanism associated with the NGN-induced anti-inflammatory effect. We found that a pretreatment with NGN at 80 µM for 2 h decreased the levels of pro-inflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) in PQ-treated SH-SY5Y cells. The production of nitric oxide (NO·) and levels of cyclooxygenase-2 (COX-2) and of the inducible isoform of nitric oxide synthase (iNOS) were downregulated by NGN in the cells exposed to PQ. Moreover, NGN downregulated the activation of the nuclear factor-κB (NF-κB) in PQ-treated cells. The anti-apoptotic and anti-inflammatory effects promoted by NGN were abolished by ZnPP IX (a specific inhibitor of HO-1) or by knockdown of Nrf2 by small interfering RNA (siRNA). Therefore, NGN induced anti-inflammatory effects in PQ-treated SH-SY5Y cells by a mechanism associated with the Nrf2/HO-1 signaling pathway.

Resveratrol and the mitochondria: From triggering the intrinsic apoptotic pathway to inducing mitochondrial biogenesis, a mechanistic view.

BACKGROUND: Mitochondria, the power plants of the cell, are known as a cross-road of different cellular signaling pathways. These cytoplasmic double-membraned organelles play a pivotal role in energy metabolism and regulate calcium flux in the cells. It is well known that mitochondrial dysfunction is associated with different diseases such as neurodegeneration and cancer. A growing body of literature has shown that polyphenolic compounds exert direct effects on mitochondrial ultra-structure and function. Resveratrol is known as one of the most common bioactive constituents of red wine, which improves mitochondrial functions under in vitro and in vivo conditions. SCOPE OF REVIEW: This paper aims to review the molecular pathways underlying the beneficial effects of resveratrol on mitochondrial structure and functions. In addition, we discuss the chemistry and main sources of resveratrol. MAJOR CONCLUSIONS: Resveratrol represents the promising effects on mitochondria in different experimental models. However, there are several reports on the detrimental effects elicited by resveratrol on mitochondria. GENERAL SIGNIFICANCE: An understanding of the chemistry and source of resveratrol, its bioavailability and the promising effects on mitochondria brings a new hope to therapy of mitochondrial dysfunction-related diseases.

Pinocembrin Attenuates Mitochondrial Dysfunction in Human Neuroblastoma SH-SY5Y Cells Exposed to Methylglyoxal: Role for the Erk1/2-Nrf2 Signaling Pathway.

Pinocembrin (PB; 5,7-dihydroxyflavanone) is found in propolis and exhibits antioxidant activity in several experimental models. The antioxidant capacity of PB is associated with the activation of the nuclear factor erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway. The Nrf2/ARE axis mediates the expression of antioxidant and detoxifying enzymes, such as glutathione peroxidase (GPx), glutathione reductase (GR), heme oxygenase-1 (HO-1), and the catalytic (GCLC) and regulatory (GCLM) subunits of the rate-limiting enzyme in the synthesis of glutathione (GSH), γ-glutamate-cysteine ligase (γ-GCL). Nonetheless, it is not clear how PB exerts mitochondrial protection in mammalian cells. Human neuroblastoma SH-SY5Y cells were pretreated (4 h) with PB (0-25 µM) and then exposed to methylglyoxal (MG; 500 µM) for further 24 h. Mitochondria were isolated by differential centrifugation. PB (25 µM) provided mitochondrial protection (decreased lipid peroxidation, protein carbonylation, and protein nitration in mitochondrial membranes; decreased mitochondrial free radical production; enhanced the content of GSH in mitochondria; rescued mitochondrial membrane potential-MMP) and blocked MG-triggered cell death by a mechanism dependent on the activation of the extracellular-related kinase (Erk1/2) and consequent upregulation of Nrf2. PB increased the levels of GPx, GR, HO-1, and mitochondrial GSH. The PB-induced effects were suppressed by silencing of Nrf2 with siRNA. Therefore, PB activated the Erk1/2-Nrf2 signaling pathway resulting in mitochondrial protection in SH-SY5Y cells exposed to MG. Our work shows that PB is a strong candidate to figure among mitochondria-focusing agents with pharmacological potential.

Naringenin Attenuates H2O2-Induced Mitochondrial Dysfunction by an Nrf2-Dependent Mechanism in SH-SY5Y Cells.

Mitochondria are the major site of ATP production in mammalian cells. Furthermore, these organelles are a source and a target of reactive oxygen species (ROS), such as radical anion superoxide (O2-·) and hydrogen peroxide (H2O2). The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is the master regulator of the mammalian redox biology and controls the expression of antioxidant and phase II detoxifying enzymes in several cell types. Naringenin (NGN, 5,7-dihydroxy-2-(4-hydroxyphenyl)-2,3-dihydrochromen-4-one), a flavanone, exhibits cytoprotective effects by acting as an antioxidant and anti-inflammatory agent. NGN is a potent activator of Nrf2. Nonetheless, it was not examine yet whether NGN would induce mitochondrial protection in cells under redox stress. Therefore, we investigate here whether Nrf2 would be involved in the mitochondrial protection elicited by NGN in SH-SY5Y cells exposed to H2O2. We observed that a pretreatment with NGN at 80 µM for 2 h reduced the levels of lipid peroxidation, protein carbonylation, and protein nitration in the membranes of mitochondria obtained from H2O2-treated SH-SY5Y cells. Additionally, NGN prevented the H2O2-induced impairment in the function of the enzymes aconitase, α-ketoglutarate dehydrogenase, and succinate dehydrogenase. The activites of the complexes I and V, as well as the production of ATP, were restored by NGN. NGN also suppressed the H2O2-induced mitochondria-related apoptosis. Interestingly, NGN promoted an increase in the levels of both total and mitochondrial glutathione (GSH). Silencing of Nrf2 abolished the protective effects induced by NGN. Overall, NGN induced mitochondrial protection by an Nrf2-dependent mechanism in H2O2-treated SH-SY5Y cells.

The Effects of Ellagic Acid upon Brain Cells: A Mechanistic View and Future Directions.

Ellagic acid (EA, 2,3,7,8-tetrahydroxy-chromeno; C14H6O8) is a polyphenol derived from fruits (pomegranates, berries) and nuts. EA exhibits antioxidant capacity and induces anti-inflammatory actions in several mammalian tissues. EA has been characterized as a possible neuroprotective agent, but the number of reports is still limited to conclude whether and how EA exerts neuroprotection in humans. In this regard, performing additional studies considering the potential beneficial and/or toxicological roles for EA on brain cells would be an important step towards fully understanding of when and how EA may be securely utilized by humans as a neuroprotective agent. The aim of the present work is to discuss data related to the neuronal and glial effects of EA and the mechanisms underlying such events. Moreover, future directions are suggested as a potential guide to be utilized by researchers interested in investigating the neuronal and glial actions of EA hereafter.

The effects of baicalein and baicalin on mitochondrial function and dynamics: A review.

Mitochondria play an essential role in cell survival by providing energy, calcium buffering, and regulating apoptosis. A growing body of evidence shows that mitochondrial dysfunction and its consequences, including impairment of the mitochondrial respiratory chain, excessive generation of reactive oxygen species, and excitotoxicity, play a pivotal role in the pathogenesis of different diseases such as neurodegenerative diseases, neuropsychiatric disorders, and cancer. The therapeutical role of flavonoids on these diseases is gaining increasing acceptance. Numerous studies on experimental models have revealed the favorable role of flavonoids on mitochondrial function and structure. This review highlights the promising role of baicalin and its aglycone form, baicalein, on mitochondrial function and structure with a focus on its therapeutic effects. We also discuss their chemistry, sources and bioavailability.

Effects of Extracts of Two Selected Strains of Haematococcus pluvialis on Adipocyte Function.

Recently, microalgae are arousing considerable interest as a source of countless molecules with potential impacts in the nutraceutical and pharmaceutical fields. Haematococcus pluvialis, also named Haematococcus lacustris, is the largest producer of astaxanthin, a carotenoid exhibiting powerful health effects, including anti-lipogenic and anti-diabetic activities. This study was carried out to investigate the properties of two selected strains of H. pluvialis (FBR1 and FBR2) on lipid metabolism, lipolysis and adipogenesis using an in vitro obesity model. FBR1 and FBR2 showed no antiproliferative effect at the lowest concentration in 3T3-L1 adipocytes. Treatment with FBR2 extract reduced lipid deposition, detected via Oil Red O staining and the immunocontent of the adipogenic proteins PPARγ, ACLY and AMPK was revealed using Western blot analysis. Extracts from both strains induced lipolysis in vitro and reduced the secretion of interleukin-6 and tumor necrosis factor-α. Moreover, the FBR1 and FBR2 extracts improved mitochondrial function, reducing the levels of mitochondrial superoxide anion radical and increasing mitochondrial mass compared to untreated adipocytes. These findings suggest that FBR2 extract, more so than FBR1, may represent a promising strategy in overweight and obesity prevention and treatment.

Short-term effectiveness of transcranial direct current stimulation in the nociceptive behavior of neuropathic pain rats in development.

Neuropathic pain (NP) is caused by a lesion that triggers pain chronification and central sensitization and it can develop in a different manner, dependent of age. Recent studies have demonstrated the efficacy of transcranial direct current stimulation (tDCS) for treating NP. Then, we aimed to investigate the effects of tDCS and BDNF levels in neuropathic pain rats in development, with 30 days old in the beginning of experiments. Eight-five male Wistar rats were subjected to chronic constriction injury. After establishment of NP, bimodal tDCS was applied to the rats for eight consecutive days, for 20 minutes each session. Subsequently, nociceptive behavior was assessed at baseline, 14 days after surgery, 1 day and 7 days after the end of tDCS. The rats were sacrificed 8 days after the last session of tDCS. An increase in the nociceptive threshold was observed in rats in development 1 day after the end of tDCS (short-term effect), but this effect was not maintained 7 days after the end of tDCS (long-term effect). Furthermore, brain derived neurotrophic factor (BDNF) levels were analyzed in the frontal cortex, spinal cord and serum using ELISA assays. The neuropathic pain model showed an effect of BDNF in the spinal cord of rats in development. There were no effects of BNDF levels of pain or tDCS in the frontal cortex or serum. In conclusion, tDCS is an effective technique to relieve nociceptive behavior at a short-term effect in neuropathic pain rats in development, and BDNF levels were not altered at long-term effect.

How environmental conditions affect sleep? An investigation in domestic dogs (Canis lupus familiaris).

Studies with humans and some other animal species have shown that sleep is compromised when the presence of external factors such as light, sound, and temperature surpass normal levels. This study investigated the effects of these environmental conditions on 13 kennelled laboratory dogs, assessing whether each variable interfered with their sleep behaviour and/or increased stress responses, which could further compromise sleep quality. The behaviour of dogs was video recorded for eight months. Diurnal and nocturnal behaviour were recorded, along with naturally occurring levels of temperature, light and sound in the dogs' kennel environment. Faecal cortisol metabolites (FCM), from samples collected every morning, were used to monitor the dogs' adrenocortical activity. GLMM models and non-parametric tests were conducted to evaluate the relationship between sleeping patterns, environmental variables, and stress on the studied dogs. Nocturnal sleep decreased in response to increases in temperature and in day light duration. No effects of sound and FCM levels on dogs' sleep were observed. However, diurnal sleep was affected by sound and FCM levels, decreasing when both factors increased. Additionally, noisier days increased stress responses, especially in male dogs. Increased FCM levels were associated with changes in the diurnal behaviour of dogs; for example, decreased activity. The decrease in daily activities and increased physiological stress responses could be associated with maladaptation to the environment, which could indicate poor welfare. Our study suggests that mitigating the impact of environmental conditions in the kennels could improve sleep quality and the overall quality of life of the dogs.

A Pretreatment with Isoorientin Attenuates Redox Disruption, Mitochondrial Impairment, and Inflammation Caused by Chlorpyrifos in a Dopaminergic Cell Line: Involvement of the Nrf2/HO-1 Axis.

The C-glucosyl flavone isoorientin (ISO) is obtained by humans from the diet and exhibits several cytoprotective effects, as demonstrated in different experimental models. However, it was not previously shown whether ISO would be able to prevent mitochondrial impairment in cells exposed to a chemical stressor. Thus, we treated the human neuroblastoma SH-SY5Y cells with ISO (0.5-20 µM) for 18 h before a challenge with chlorpyrifos (CPF) at 100 µM for additional 24 h. We observed that ISO prevented the CPF-induced lipid peroxidation and protein carbonylation and nitration in the membranes of mitochondria extracted from CPF-treated cells. ISO also attenuated the CPF-elicited increase in the production of reactive species in this experimental model. Moreover, ISO prevented the CPF-induced disruption in the activity of components of the oxidative phosphorylation (OXPHOS) system in the SH-SY5Y cells. ISO also promoted an anti-inflammatory action in the cells exposed to CPF. CPF caused a decrease in the activity of the enzyme heme oxygenase-1 (HO-1), a cytoprotective agent. On the other hand, ISO upregulated HO-1 activity in SH-SY5Y cells. Inhibition of HO-1 by zinc protoporphyrin-IX (ZnPP-IX) suppressed the cytoprotection induced by ISO in the CPF-treated cells. Besides, silencing of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) abolished the ISO-induced HO-1 upregulation and mitochondrial benefits induced by this flavone on the CPF-challenged cells. Thus, ISO protected mitochondria of the CPF-treated cells by an Nrf2/HO-1-dependent fashion in the SH-SY5Y cells.