Nociceptor neurons affect cancer immunosurveillance.

Solid tumours are innervated by nerve fibres that arise from the autonomic and sensory peripheral nervous systems1-5. Whether the neo-innervation of tumours by pain-initiating sensory neurons affects cancer immunosurveillance remains unclear. Here we show that melanoma cells interact with nociceptor neurons, leading to increases in their neurite outgrowth, responsiveness to noxious ligands and neuropeptide release. Calcitonin gene-related peptide (CGRP)-one such nociceptor-produced neuropeptide-directly increases the exhaustion of cytotoxic CD8+ T cells, which limits their capacity to eliminate melanoma. Genetic ablation of the TRPV1 lineage, local pharmacological silencing of nociceptors and antagonism of the CGRP receptor RAMP1 all reduced the exhaustion of tumour-infiltrating leukocytes and decreased the growth of tumours, nearly tripling the survival rate of mice that were inoculated with B16F10 melanoma cells. Conversely, CD8+ T cell exhaustion was rescued in sensory-neuron-depleted mice that were treated with local recombinant CGRP. As compared with wild-type CD8+ T cells, Ramp1-/- CD8+ T cells were protected against exhaustion when co-transplanted into tumour-bearing Rag1-deficient mice. Single-cell RNA sequencing of biopsies from patients with melanoma revealed that intratumoral RAMP1-expressing CD8+ T cells were more exhausted than their RAMP1-negative counterparts, whereas overexpression of RAMP1 correlated with a poorer clinical prognosis. Overall, our results suggest that reducing the release of CGRP from tumour-innervating nociceptors could be a strategy to improve anti-tumour immunity by eliminating the immunomodulatory effects of CGRP on cytotoxic CD8+ T cells.

Nanophotonics Enable Targeted Photothermal Silencing of Nociceptor Neurons.

The sensory nervous and immune systems work in concert to preserve homeostasis. While this endogenous interplay protects from danger, it may drive chronic pathologies. Currently, genetic engineering of neurons remains the primary approach to interfere selectively with this potentially deleterious interplay. However, such manipulations are not feasible in a clinical setting. Here, this work reports a nanotechnology-enabled concept to silence subsets of unmodified nociceptor neurons that exploits their ability to respond to heat via the transient receptor potential vanilloid type 1 (TRPV1) channel. This strategy uses laser stimulation of antibody-coated gold nanoparticles to heat-activate TRPV1, turning this channel into a cell-specific drug-entry port. This delivery method allows transport of a charged cationic derivative of an N-type calcium channel blocker (CNCB-2) into targeted sensory fibers. CNCB-2 delivery blocks neuronal calcium currents and neuropeptides release, resulting in targeted silencing of nociceptors. Finally, this work demonstrates the ability of the approach to probe neuro-immune crosstalk by targeting cytokine-responsive nociceptors and by successfully preventing nociceptor-induced CD8+ T-cells polarization. Overall, this work constitutes the first demonstration of targeted silencing of nociceptor neuron subsets without requiring genetic modification, establishing a strategy for interfering with deleterious neuro-immune interplays.

Effects of Fish and Grape Seed Oils as Core of Haloperidol-Loaded Nanocapsules on Oral Dyskinesia in Rats.

Haloperidol is a widely used antipsychotic, despite the severe motor side effects associated with its chronic use. This study was carried out to compare oral dyskinesia induced by different formulations of haloperidol-loaded nanocapsules containing caprylic/capric triglycerides, fish oil or grape seed oil (GSO) as core, as well as free haloperidol. Haloperidol-loaded lipid-core nanocapsules formulations were prepared, physicochemical characterized and administered (0.5 mg kg-1-ip) to rats for 28 days. Oral dyskinesia was evaluated acutely and subchronically and after that cell viability and free radical generation in cortex and substantia nigra. All formulations presented satisfactory physicochemical parameters. Acutely, all formulations were able to prevent oral dyskinesia development in comparison to free haloperidol, except haloperidol-loaded nanocapsules containing GSO, whose effect was only partial. After subchronic treatment, all haloperidol-loaded nanocapsules formulations prevented oral dyskinesia in relation to free drug. Also, haloperidol-loaded nanocapsules containing fish oil and GSO were more effective than caprylic/capric triglycerides nanocapsules and free haloperidol in cell viability preservation and control of free radical generation. Our findings showed that fish oil formulation may be considered as the best formulation of haloperidol-loaded lipid-core nanocapsules, being able to prevent motor side effects associated with chronic use of antipsychotic drugs, as haloperidol.

Cross-generational trans fat intake modifies BDNF mRNA in the hippocampus: Impact on memory loss in a mania animal model.

Recently, we have described the influence of dietary fatty acids (FA) on mania-like behavior of first generation animals. Here, two sequential generations of female rats were supplemented with soybean oil (SO, rich in n-6 FA, control group), fish oil (FO, rich in n-3 FA) and hydrogenated vegetable fat (HVF, rich in trans FA) from pregnancy and during lactation. In adulthood, half of each group was exposed to an amphetamine (AMPH)-induced mania animal model for behavioral, biochemical and molecular assessments. FO supplementation was associated with lower reactive species (RS) generation and protein carbonyl (PC) levels and increased dopamine transporter (DAT) levels, while HVF increased RS and PC levels, thus decreasing catalase (CAT) activity and DAT levels in hippocampus after AMPH treatment. AMPH impaired short- (1 h) and long- (24 h) term memory in the HVF group. AMPH exposure was able to reduce hippocampal BDNF- mRNA expression, which was increased in FO. While HVF was related to higher trans FA (TFA) incorporation in hippocampus, FO was associated with increased percentage of n-3 polyunsaturated FA (PUFA) together with lower n-6/n-3 PUFA ratio. Interestingly, our data showed a positive correlation between brain-derived neurotrophic factor (BDNF) mRNA and short- and long-term memory (r(2) = 0.53; P = 0.000/r(2) = 0.32; P = 0.011, respectively), as well as a negative correlation between PC and DAT levels (r(2) = 0.23; P = 0.015). Our findings confirm that provision of n-3 or TFA during development over two generations is able to change the neuronal membrane lipid composition, protecting or impairing the hippocampus, respectively, thus affecting neurothrophic factor expression such as BDNF mRNA. In this context, chronic consumption of trans fats over two generations can facilitate the development of mania-like behavior, so leading to memory impairment and emotionality, which are related to neuropsychiatric conditions.

Polyphenolic Composition and Evaluation of Antioxidant Activity, Osmotic Fragility and Cytotoxic Effects of Raphiodon echinus (Nees & Mart.) Schauer.

Raphiodon echinus (R. echinus) is used in Brazilian folk medicine for the treatment of inflammation, coughs, and infectious diseases. However, no information is available on the potential antioxidant, cytotoxicity and genotoxicity of this plant. In this study, the polyphenolic constituents, antioxidant capacity and potential toxic effects of aqueous and ethanolic extracts of R. echinus on human erythrocytes and leukocytes were investigated for the first time. R. echinus extracts showed the presence of Gallic, chlorogenic, caffeic and ellagic acids, rutin, quercitrin and quercetin. Aqueous and ethanolic extracts of R. echinus exhibited antioxidant activity in DPPH radical scavenging with IC50 = 111.9 µg/mL (EtOH extract) and IC50 = 227.9 µg/mL (aqueous extract). The extracts inhibited Fe(2+) (10 µM) induced thiobarbituric acid reactive substances (TBARS) formation in rat brain and liver homogenates. The extracts (30-480 µg/mL) did not induce genotoxicity, cytotoxicity or osmotic fragility in human blood cells. The findings of this present study therefore suggest that the therapeutic effect of R. echinus may be, in part, related to its antioxidant potential. Nevertheless, further in vitro and in vivo studies are required to ascertain the safety margin of its use in folk medicine.

Differential expression of alpha-synuclein in the hippocampus of SHR and SLA16 isogenic rat strains.

Two inbred strains, Lewis (LEW) and Spontaneously Hypertensive Rats (SHR), are well-known for their contrasting behavior related to anxiety/emotionality. Studies with these two strains led to the discovery of the Quantitative Trait Loci (QTL) on chromosome 4 (Anxrr16). To better understand the influences of this genomic region, the congenic rat strain SLA16 (SHR.LEW-Anxrr16) was developed. SLA16 rats present higher hyperactivity/impulsivity, deficits in learning and memory, and lower basal blood pressure than the SHR strain, even though genetic differences between them are only in chromosome 4. Thus, the present study proposed the alpha-synuclein and the dopaminergic system as candidates to explain the differential behavior of SHR and SLA16 strains. To accomplish this, beyond the behavioral analysis, we performed (I) the Snca gene expression and (II) quantification of the alpha-synuclein protein in the hippocampus (HPC), prefrontal cortex (PFC), and striatum (STR) of SHR and SLA16 strains; (III) sequencing of the 3'UTR of the Snca gene; and (IV) evaluation of miRNA binding in the 3'UTR site. A Single Nucleotide Polymorphism (SNP) was identified in the 3'UTR of the Snca gene, which exhibited upregulation in the HPC of SHR compared to SLA16 females. Alpha-synuclein protein was higher in the HPC of SHR males compared to SLA16 males. The results of this work suggested that differences in alpha-synuclein HPC content could be influenced by miRNA regulation and associated with behavioral differences between SHR and SLA16 animals.

Neonatal handling prevents anxiety-like symptoms in rats exposed to chronic mild stress: behavioral and oxidative parameters.

This study investigated the influence of neonatal handling on behavioral and biochemical consequences of chronic mild stress (CMS) in adulthood. Male rat pups were submitted to daily tactile stimulation (TS) or maternal separation (MS), from postnatal day 1 (PND1) to postnatal day 21 (PND21), for 10 min/day. In adulthood, half the number of animals were exposed to CMS for 3 weeks and submitted to behavioral testing, including sucrose preference (SP), elevated plus maze (EPM), and defensive burying tasks (DBTs), followed by biochemical assessments. CMS reduced SP, increased anxiety in EPM and DBT, and increased adrenal weight. In addition, CMS decreased plasma vitamin C (VIT C) levels and increased protein carbonyl (PC) levels, catalase (CAT) activity in hippocampus and cortex, and superoxide dismutase (SOD) levels in cortex. In contrast, both forms of neonatal handling were able to prevent reduction in SP, anxiety behavior in DBT, and CMS-induced adrenal weight increase. Furthermore, they were also able to prevent plasma VIT C reduction, hippocampal PC levels increase, CAT activity increase in hippocampus and cortex, and SOD levels increase in cortex following CMS. Only TS was able to prevent CMS-induced anxiety symptoms in EPM and PC levels in cortex. Taken together, these findings show the protective role of neonatal handling, especially TS, which may enhance ability to cope with stressful situations in adulthood.

LIST: A Newly Developed Laser-assisted Cell Bioprinting Technology.

Cell bioprinting technologies aim to fabricate tissue-like constructs by delivering biomaterials layer-by-layer. Bioprinted constructs can reduce the use of animals in drug development and hold promise for addressing the shortage of organs for transplants. We recently introduced a laser-assisted drop-on-demand bioprinting technology termed Laser Induced Side Transfer (LIST). This technology can print delicate cell types, including primary neurons. This bioprinting protocol includes the following key steps: cell harvesting, bio-ink preparation, laser setup priming, printing, and post-printing analysis. This protocol includes a detailed description of the laser setup, which is a rather unusual setup for a biology lab. This should allow easy reproduction by readers with basic knowledge of optics. Although we have focused on neuron bioprinting, interested readers will be able to adapt the protocol to bioprint virtually any cell type.

Teasing Out the Interplay Between Natural Killer Cells and Nociceptor Neurons.

Somatosensory neurons have evolved to detect noxious stimuli and activate defensive reflexes. By sharing means of communication, nociceptor neurons also tune host defenses by controlling the activity of the immune system. The communication between these systems is mostly adaptive, helping to protect homeostasis, it can also lead to, or promote, the onset of chronic diseases. Both systems co-evolved to allow for such local interaction, as found in primary and secondary lymphoid tissues and mucosa. Recent studies have demonstrated that nociceptors directly detect and respond to foreign antigens, immune cell-derived cytokines, and microbes. Nociceptor activation not only results in pain hypersensitivity and itching, but lowers the nociceptor firing threshold, leading to the local release of neuropeptides. The peptides that are produced by, and released from, the peripheral terminals of nociceptors can block the chemotaxis and polarization of lymphocytes, controlling the localization, duration, and type of inflammation. Recent evidence shows that sensory neurons interact with innate immune cells via cell-cell contact, for example, engaging group 2D (NKG2D) receptors on natural killer (NK) cells. Given that NK cells express the cognate receptors for various nociceptor-produced mediators, it is conceivable that nociceptors use neuropeptides to control the activity of NK cells. Here, we devise a co-culture method to study nociceptor neuron-NK cell interactions in a dish. Using this approach, we found that lumbar nociceptor neurons decrease NK cell cytokine expression. Overall, such a reductionist method could be useful to study how tumor-innervating neurons control the anticancer function of NK cells and how NK cells control the elimination of injured neurons.

Bioprinting of Adult Dorsal Root Ganglion (DRG) Neurons Using Laser-Induced Side Transfer (LIST).

Cell bioprinting technologies aim to fabricate tissuelike constructs by delivering biomaterials layer-by-layer. Bioprinted constructs can reduce the use of animals in drug development and hold promise for addressing the shortage of organs for transplants. Here, we sought to validate the feasibility of bioprinting primary adult sensory neurons using a newly developed laser-assisted cell bioprinting technology, known as Laser-Induced Side Transfer (LIST). We used dorsal root ganglion neurons (DRG; cell bodies of somatosensory neurons) to prepare our bioink. DRG-laden- droplets were printed on fibrin-coated coverslips and their viability, calcium kinetics, neuropeptides release, and neurite outgrowth were measured. The transcriptome of the neurons was sequenced. We found that LIST-printed neurons maintain high viability (Printed: 86%, Control: 87% on average) and their capacity to release neuropeptides (Printed CGRP: 130 pg/mL, Control CGRP: 146 pg/mL). In addition, LIST-printed neurons do not show differences in the expressed genes compared to control neurons. However, in printed neurons, we found compromised neurite outgrowth and lower sensitivity to the ligand of the TRPV1 channel, capsaicin. In conclusion, LIST-printed neurons maintain high viability and marginal functionality losses. Overall, this work paves the way for bioprinting functional 2D neuron assays.

Neuro-Immunity and Gut Dysbiosis Drive Parkinson's Disease-Induced Pain.

Parkinson's disease (PD) is the second most common neurodegenerative disorder, affecting 1-2% of the population aged 65 and over. Additionally, non-motor symptoms such as pain and gastrointestinal dysregulation are also common in PD. These impairments might stem from a dysregulation within the gut-brain axis that alters immunity and the inflammatory state and subsequently drives neurodegeneration. There is increasing evidence linking gut dysbiosis to the severity of PD's motor symptoms as well as to somatosensory hypersensitivities. Altogether, these interdependent features highlight the urgency of reviewing the links between the onset of PD's non-motor symptoms and gut immunity and whether such interplays drive the progression of PD. This review will shed light on maladaptive neuro-immune crosstalk in the context of gut dysbiosis and will posit that such deleterious interplays lead to PD-induced pain hypersensitivity.

Trans fat intake during pregnancy or lactation increases anxiety-like behavior and alters proinflammatory cytokines and glucocorticoid receptor levels in the hippocampus of adult offspring.

Changes in dietary habits, including the increased consumption of processed foods, rich in trans fatty acids (TFA), have profound effects on offspring health in later life. Thus, this study aimed to assess the influence of maternal trans fat intake during pregnancy or lactation on anxiety behavior, as well as markers of inflammation, oxidative stress, and expression of glucocorticoid receptors (GR) of adult male offspring. Female Wistar rats were supplemented daily with soybean oil/fish oil (SO/FO) or hydrogenated vegetable fat (HVF) by oral gavage (3.0 g/kg body weight) during pregnancy or lactation. After weaning, male offspring received only standard diet. On the postnatal day 60, anxiety-like symptoms were assessed, the plasma was collected for the quantification of cytokines levels and the hippocampus removed for biochemical and molecular analysis. Our findings have evidenced that offspring from HVF-supplemented dams during pregnancy or lactation showed significantly greater levels of anxiety behavior. HVF supplementation increased plasma levels of proinflammatory cytokines and these levels were higher in the lactation period. In contrast, HVF supplementation decreased plasma levels of IL-10 in relation to SO/FO in both periods. Biochemical evaluations showed higher reactive species generation, protein carbonyl levels and catalase activity in offspring from HVF-supplemented dams during lactation. In addition, offspring from HVF-supplemented dams showed decreased GR expression in both supplemented periods. Together, these data indicate that consumption of TFA in different periods of development may increase anxiety-like behavior at least in part via alterations in proinflammatory and anti-inflammatory cytokine levels and GR expression in limbic brain regions.

Engineering immunoproteasome-expressing mesenchymal stromal cells: A potent cellular vaccine for lymphoma and melanoma in mice.

Dendritic cells (DCs) excel at cross-presenting antigens, but their effectiveness as cancer vaccine is limited. Here, we describe a vaccination approach using mesenchymal stromal cells (MSCs) engineered to express the immunoproteasome complex (MSC-IPr). Such modification instills efficient antigen cross-presentation abilities associated with enhanced major histocompatibility complex class I and CD80 expression, de novo production of interleukin-12, and higher chemokine secretion. This cross-presentation capacity of MSC-IPr is highly dependent on their metabolic activity. Compared with DCs, MSC-IPr hold the ability to cross-present a vastly different epitope repertoire, which translates into potent re-activation of T cell immunity against EL4 and A20 lymphomas and B16 melanoma tumors. Moreover, therapeutic vaccination of mice with pre-established tumors efficiently controls cancer growth, an effect further enhanced when combined with antibodies targeting PD-1, CTLA4, LAG3, or 4-1BB under both autologous and allogeneic settings. Therefore, MSC-IPr constitute a promising subset of non-hematopoietic antigen-presenting cells suitable for designing universal cell-based cancer vaccines.

Guanosine prevents depressive-like behaviors in rats following bilateral dorsolateral striatum lesion induced by 6-hydroxydopamine.

The dorsolateral striatum (DLS) processes motor and non-motor functions and undergoes extensive dopaminergic degeneration in Parkinson's disease (PD). Beyond the nigrostriatal pathway, dopaminergic degeneration also affects other brain areas including the pre-frontal cortex (PFC) and hippocampus, which have been associated with the appearance of anhedonia and depression at pre-motor phases of PD. Herein, using behavioral and biochemical approaches, we investigated the protective effects of guanosine (GUO) (7.5 mg/kg, i.p.) against emotional impairments and cellular events in cortical, striatal and hippocampal slices of rats submitted to a bilateral infusion of 6-OHDA (10 µg/hemisphere) into the DLS. 6-OHDA-lesioned rats displayed anhedonic- and depressive-like behaviors addressed in the splash and forced swimming tests (at 8 and 21 days after lesion, respectively). In addition, no alterations in motor performance in the open field test and social interaction were observed. Biochemical analyses were performed 22 days after 6-OHDA lesions. 6-OHDA lesion induced hippocampal mitochondrial membrane potential disruption. However, intra-striatal 6-OHDA administration did not alter the ROS levels measured in cortical, striatal and hippocampal slices. GUO treatment attenuated anhedonic- and depressive-like behaviors in 6-OHDA-lesioned rats and protected hippocampal slices against the mitochondrial membrane potential disruption. These results indicate antidepressant-like effects of GUO in a rat model of PD, indicating the potential of GUO for the treatment of depression associated with PD.

Temporal development of behavioral impairments in rats following locus coeruleus lesion induced by 6-hydroxydopamine: Involvement of ß3-adrenergic receptors.

Noradrenergic degeneration in the locus coeruleus (LC) seems a convergent neuropathological marker of different neurodegenerative diseases. Herein, we investigated the temporal development of apoptotic signaling activation in the LC, noradrenergic dysfunction and behavioral impairments in rats following the noradrenergic lesion of the LC. For this purpose, the dopamine reuptake inhibitor nomifensine was administered 1 h before the stereotaxic bilateral injections of 6-hydroxydopamine (6-OHDA; 5, 10 or 20 µg/hem) into the LC. The behavioral and neurochemical analyses were performed at 7, 21 and 42 days after 6-OHDA injections. All doses of 6-OHDA induced neuronal death in LC, but only the highest dose (20 µg/hem) disrupted the motor function. 6-OHDA (5 µg/hem) injection induced short-term memory deficits in all periods, olfactory discrimination and long-term memory impairments at 7 days, and depressive-like behaviors at 21 and 42 days after injection. Moreover, 6-OHDA infusion increased Bax/Bcl2 ratio and caspase 3 levels, and decreased the dopamine ß-hydroxylase immunocontent in the LC. Noradrenergic neurotransmission dysfunction was observed in the LC, olfactory bulb, prefrontal cortex, hippocampus and striatum. The intranasal (i.n.) noradrenaline (NA) infusion restored the impairments in the olfactory discrimination, short-term memory and depressive-like behavior of 6-OHDA-lesioned rats. In addition, these effects were blocked by the prior i.n. infusion of the ß3-adrenergic receptor antagonist SR59230A. These findings indicate that the 6-OHDA injection into the LC induced the apoptosis signaling activation, noradrenergic neurotransmission dysfunction and behavioral impairments that were restored via ß3-adrenergic receptors activation mediated by the i.n. NA administration.

The influence of chromosome 4 on metabolism and spatial memory in SHR and SLA16 rat strains.

The Spontaneously Hypertensive Rat (SHR) has been proposed as a good model to study the pathways related to neurodegenerative diseases and glucose intolerance. Our research group developed the SLA16 (SHR.LEW-Anxrr16) congenic strain, which is genetically identical to the SHR strain, except for a locus on chromosome 4 (DGR). We applied in silico analysis on DGR to evaluate the association of their genes with neurobiological and metabolic pathways. After, we characterized cholesterol, triglycerides, metabolism of glucose and the behavioral performance of young (2 months old) and adult (8 months old) SHR and SLA16 rats in the open field, object location and water maze tasks. Finally, naïve young rats were repeatedly treated with metformin (200 mg/kg; v.o.) and evaluated in the same tests. Bioinformatics analysis showed that DGR presents genes related to glucose metabolism, oxidative damage and neurodegenerative diseases. Young SLA16 presented higher cholesterol, triglycerides, glucose and locomotion in the open field than SHR rats. In adulthood, SLA16 rats presented high triglycerides and locomotion in the open field and impairment on spatial learning and memory. Finally, the treatment with metformin decreased the glucose tolerance curve and also improved long-term memory in SLA16 rats. These results indicate that DGR presents genes associated with metabolic pathways and neurobiological processes that may produce alterations in glucose metabolism and spatial learning/memory. Therefore, we suggest that SHR and SLA16 strains could be important for the study of genes and subsequent mechanisms that produce metabolic glucose alterations and age-related cognitive deficits.

Maternal trans fat intake during pregnancy or lactation impairs memory and alters BDNF and TrkB levels in the hippocampus of adult offspring exposed to chronic mild stress.

This study aimed to assess the influence of maternal dietary fat intake during pregnancy or lactation on memory of adult offspring after chronic mild stress (CMS) exposure. Female Wistar rats were supplemented daily with soybean oil/fish oil (SO/FO) or hydrogenated vegetable fat (HVF) by oral gavage (3.0g/kg body weight) during pregnancy or lactation. On post-natal day (PND) 60, half of the animals were exposed to CMS following behavioral assessments. While the adult offspring born under influence of SO/FO and HVF supplementations during pregnancy showed higher levels of n-3 and n-6 fatty acids (FA) series DHA and ARA metabolites, respectively, in the hippocampus, adult offspring born from supplemented dams during lactation showed higher levels of their precursors: ALA and LA. However, only HVF supplementation allowed TFA incorporation of adult offspring, and levels were higher in lactation period. Adult offspring born from dams supplemented with trans fat in both pregnancy and lactation showed short and long-term memory impairments before and after CMS. Furthermore, our study also showed higher memory impairment in offspring born from HVF-supplemented dams during lactation in comparison to pregnancy. BDNF expression was increased by stress exposure in offspring from both SO/FO- and HVF-supplemented dams during pregnancy. In addition, offspring from HVF-supplemented dams showed decreased TrkB expression in both supplemented periods, regardless of stress exposure. In conclusion, these findings show for the first time that the type of dietary FA as well as the period of brain development is able to change FA incorporation in brain neural membranes.

Safety assessment and antioxidant activity of Lantana montevidensis leaves: Contribution to its phytochemical and pharmacological activity.

Lantana camara, the widely studied species, and L. montevidensis, the less studied species of the genus Lantana are both used in traditional medicine for the same purpose (anti-asthma, anti-ulcer, anti-tumor, etc). However, little is known about the toxicity of L. montevidensis and there is limited information on its chemical constituents. Here, we investigated for the first time the genotoxicity and cytotoxicity of the ethanolic (EtOH) and aqueous extracts from the leaves of Lantana montevidensis in human leukocytes, as well as their possible interaction with human erythrocyte membranes in vitro. The antioxidant activities of both extracts were also investigated in chemical and biological models. Treatment of leukocytes with EtOH or aqueous extracts (1-480 µg/mL) did not affect DNA damage index, but promoted cytotoxicity at higher concentrations (240-480 µg/mL). Both extracts did not modify the osmotic fragility of human erythrocytes. The extracts scavenged DPPH radical and prevented Fe2+-induced lipid peroxidation in rat's brain and liver homogenates, and this was likely not attributed to Fe (II) chelation. The HPLC analysis of the extracts showed different amounts of polyphenolic compounds (isoquercitrin, gallic acid, catechin, ellagic acid, apigenin, kaempferol, caffeic acid, rutin, quercitrin, quercetin, chlorogenic acid, luteolin) that may have contributed to these effects. These results supported information on the functional use of L. montevidensis in folk medicine.

Trans fat intake across gestation and lactation increases morphine preference in females but not in male rats: Behavioral and biochemical parameters.

The abuse of morphine has risen considerably in recent years, mainly due to the increase of its prescription in clinical medicine. Also, increased consumption of processed foods, rich in trans fatty acids (TFA), has caused concerns about human health. Thus, the aim of our study was to determine whether trans fat consumption in the perinatal period may affect preference for morphine in adolescent female and male rats. Dams were orally supplemented with water (C-control) or hydrogenated vegetable fat (HVF-rich in TFA) during gestation and lactation periods. On post-natal day 43, pups were exposed to morphine (4mg/kg i.p., for 4 days) and assessed in the conditioned place preference paradigm. Anxiety-like symptoms were assessed, and oxidative status of the brain was estimated by reactive species (RS) generation. Female rats with HVF supplementation showed increased morphine preference and less anxiety-like symptoms. Additionally, both male and female rats from HVF-supplementation showed increased RS generation in the ventral tegmental area, whose level was similar in morphine-conditioned female rats. RS generation was increased in the hippocampus of morphine-conditioned female rats, regardless of the supplementation of their dams. We may infer that gender is a predictive factor to opioid preference, since adolescent female rats showed more susceptibility to addiction than males. Furthermore, trans fat consumption across the perinatal period is able to modify parameters of opioid preference in female rats, possibly due to TFA incorporation in phospholipid membranes, modifying the endogenous opioid system and the oxidative status in brain areas related to drug addiction.

A surface modification of clozapine-loaded nanocapsules improves their efficacy: A study of formulation development and biological assessment.

This work aimed to develop nanocapsules (NC) coated with polysorbate 80 (P80), cationic chitosan (CS) or polyethylene glycol (PEG) using clozapine (CZP) as the drug model. The zeta potential, pH and encapsulation efficiency were directly affected by the CS coating. Using the bag dialysis method, the in vitro CZP release from CS-coated nanocapsules was similar to the PEG-coated at pH 7.4. Nanocapsules coated with PEG and CS exhibited an increased action duration compared to the P80-coated nanocapsules in pseudo-psychosis induced by d,l-amphetamine in rats. When comparing both groups, the group administered CS-coated nanocapsules showed better activity than the PEG-coated nanocapsules at 6, 10 and 12h after d,l-amphetamine administration. The pharmacokinetic assessment in rats demonstrated that the observed half-lives were free CZP