Human milk beyond nutrition role to functional and adaptative physiological functions

Human milk contains a large amount of various proteins that contribute to the newborn's quality of life. These proteins, when digested, are transformed into peptides and amino acids that help in better absorption of nutrients from milk, some of them such as; amylase, beta- casein, lactoferrin , among others. They also have several activities, such as; immunomodulators , antihypertensives , antimicrobials, antithrombotics and others ( Lönnerdal , 2003). Human milk can be divided into three phases; colostrum, transitional milk and mature milk, and in these three different phases of milk the composition of proteins, peptides, amino acids, sugars and all other components fluctuate a lot. Many of the proteins are synthesized in the mammary gland, with some exceptions such as serum albumin which comes from the blood circulation . Currently, due to the great diversity and quantity of proteins and peptides in human milk, there are large studies on their properties such as; function and quantification of human milk proteins and peptides. With a view to better nutrition for newborns, better identification and biochemical characterization of these compounds. To this end, several steps will be carried out to isolate and characterize new peptides and proteins from human milk and the activities of the new peptides and proteins found in human milk will also be tested. These activity tests will be carried out in cell culture (cell proliferation or cell inhibition effect), blood pressure in rats (hypotensive or hypertensive effects ) and guinea pig ileum (contractile or relaxing effect). Once a peptide or protein with significant function or activity is isolated, peptidomic or cryptic analysis can then be carried out . New insights obtained with proteomics and metabolomics approaches revealed new components present in human milk including cryptides that could be generated in certain conditions by the newborn microbiome Therefore, by better characterizing human milk and its components, there will be better and greater conditions for understanding the nutrition of newborns and premature babies and a better understanding of the physiological role played by these components in relation to the development and growth of the newborn.

Captive maintenance and venom extraction of Tityus serrulatus (Brazilian yellow scorpion) for antivenom production

Scorpion envenomation is a public health problem in several tropical and subtropical countries. Tityus serrulatus Lutz and Mello, 1922 (Brazilian yellow scorpion) are responsible for approximately 150,000 envenoming cases per year in Brazil, of which 10% require antivenom treatment to reverse life-threatening venom effects. Therefore, thousands of T. serrulatus individuals are maintained under controlled captivity conditions for venom extraction, subsequently used in the production of the national supply of scorpion antivenom. Instituto Butantan is the main antivenom-manufacturing laboratory in Brazil, providing about 70,000 vials of scorpion antivenom for the Brazilian health system. Thus, the husbandry protocols and venom extraction methodologies are key points for the success of large-scale, standardized venom production. The objective of this article is to describe the captivity protocols of T. serrulatus husbandry, encompassing the husbandry routine and the venom extraction procedures, following good manufacturing practices, and ensuring animal welfare. These practices allow for the maintenance of up to 20,000 animals in captivity, with a routine of 3,000 to 5,000 scorpions milked monthly according to antivenom manufacturing demand, achieving an average of 90% of positive extraction.

Effect of Subthalamic Stimulation and Electrode Implantation in the Striatal Microenvironment in a Parkinson's Disease Rat Model.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is considered the gold-standard treatment for PD; however, underlying therapeutic mechanisms need to be comprehensively elucidated, especially in relation to glial cells. We aimed to understand the effects of STN-microlesions and STN-DBS on striatal glial cells, inflammation, and extracellular glutamate/GABAergic concentration in a 6-hydroxydopamine (6-OHDA)-induced PD rat model. Rats with unilateral striatal 6-OHDA and electrodes implanted in the STN were divided into two groups: DBS OFF and DBS ON (5 days/2 h/day). Saline and 6-OHDA animals were used as control. Akinesia, striatal reactivity for astrocytes, microglia, and inflammasome, and expression of cytokines, cell signaling, and excitatory amino acid transporter (EAAT)-2 were examined. Moreover, striatal microdialysis was performed to evaluate glutamate and GABA concentrations. The PD rat model exhibited akinesia, increased inflammation, glutamate release, and decreased glutamatergic clearance in the striatum. STN-DBS (DBS ON) completely abolished akinesia. Both STN-microlesion and STN-DBS decreased striatal cytokine expression and the relative concentration of extracellular glutamate. However, STN-DBS inhibited morphological changes in astrocytes, decreased inflammasome reactivity, and increased EAAT2 expression in the striatum. Collectively, these findings suggest that the beneficial effects of DBS are mediated by a combination of stimulation and local microlesions, both involving the inhibition of glial cell activation, neuroinflammation, and glutamate excitotoxicity.

Anti-SARS-CoV-2 equine F (Ab')2 immunoglobulin as a possible therapy for COVID-19.

The new outbreak of coronavirus disease 2019 (COVID-19) has infected and caused the death of millions of people worldwide. Intensive efforts are underway around the world to establish effective treatments. Immunoglobulin from immunized animals or plasma from convalescent patients might constitute a specific treatment to guarantee the neutralization of the virus in the early stages of infection, especially in patients with risk factors and a high probability of progressing to severe disease. Worldwide, a few clinical trials using anti-SARS-CoV-2 immunoglobulins from horses immunized with the entire spike protein or fragments of it in the treatment of patients with COVID-19 are underway. Here, we describe the development of an anti-SARS-CoV-2 equine F(ab')2 immunoglobulin using a newly developed SARS-CoV-2 viral antigen that was purified and inactivated by radiation. Cell-based and preclinical assays showed that the F(ab')2 immunoglobulin successfully neutralizes the virus, is safe in animal models, and reduces the severity of the disease in a hamster model of SARS-CoV-2 infection and disease.

Long-term follow-up on bilateral posterior hypothalamic deep brain stimulation for treating refractory aggressive behavior in a patient with Cri du chat syndrome: analysis of clinical data, intraoperative microdialysis, and imaging connectomics

Posterior hypothalamic-deep brain stimulation (pHyp-DBS) has been reported as a successful treatment for reducing refractory aggressive behaviors in patients with distinct primary diagnoses. Here, we report on a patient with cri du chat syndrome presenting severe self-injury and aggressive behaviors toward others, who was treated with pHyp-DBS. Positive results were observed at long-term follow-up in aggressive behavior and quality of life. Intraoperative microdialysis and imaging connectomics analysis were performed to investigate possible mechanisms of action. Our results suggest the involvement of limbic and motor areas and alterations in main neurotransmitter levels in the targeted area that are associated with positive results following treatment.

Effect of subthalamic stimulation and electrode implantation in the striatal microenvironment in a parkinson’s disease rat model

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is considered the goldstandard treatment for PD; however, underlying therapeutic mechanisms need to be comprehensively elucidated, especially in relation to glial cells. We aimed to understand the effects of STN-microlesions and STN-DBS on striatal glial cells, inflammation, and extracellular glutamate/GABAergic concentration in a 6-hydroxydopamine (6-OHDA)-induced PD rat model. Rats with unilateral striatal 6-OHDA and electrodes implanted in the STN were divided into two groups: DBS OFF and DBS ON (5 days/2 h/day). Saline and 6-OHDA animals were used as control. Akinesia, striatal reactivity for astrocytes, microglia, and inflammasome, and expression of cytokines, cell signaling, and excitatory amino acid transporter (EAAT)-2 were examined. Moreover, striatal microdialysis was performed to evaluate glutamate and GABA concentrations. The PD rat model exhibited akinesia, increased inflammation, glutamate release, and decreased glutamatergic clearance in the striatum. STN-DBS (DBS ON) completely abolished akinesia. Both STN-microlesion and STN-DBS decreased striatal cytokine expression and the relative concentration of extracellular glutamate. However, STN-DBS inhibited morphological changes in astrocytes, decreased inflammasome reactivity, and increased EAAT2 expression in the striatum. Collectively, these findings suggest that the beneficial effects of DBS are mediated by a combination of stimulation and local microlesions, both involving the inhibition of glial cell activation, neuroinflammation, and glutamate excitotoxicity.

Anti-SARS-CoV-2 equine F (Ab′)2 immunoglobulin as a possible therapy for COVID-19

The new outbreak of coronavirus disease 2019 (COVID-19) has infected and caused the death of millions of people worldwide. Intensive efforts are underway around the world to establish effective treatments. Immunoglobulin from immunized animals or plasma from convalescent patients might constitute a specific treatment to guarantee the neutralization of the virus in the early stages of infection, especially in patients with risk factors and a high probability of progressing to severe disease. Worldwide, a few clinical trials using anti-SARS-CoV-2 immunoglobulins from horses immunized with the entire spike protein or fragments of it in the treatment of patients with COVID-19 are underway. Here, we describe the development of an anti-SARS-CoV-2 equine F(ab′)2 immunoglobulin using a newly developed SARS-CoV-2 viral antigen that was purified and inactivated by radiation. Cell-based and preclinical assays showed that the F(ab′)2 immunoglobulin successfully neutralizes the virus, is safe in animal models, and reduces the severity of the disease in a hamster model of SARS-CoV-2 infection and disease.

Directional deep brain stimulation of the posteromedial hypothalamus for refractory intermittent explosive disorder: a case series using a novel neurostimulation device and intraoperative microdialysis

Intermittent Explosive Disorder (IED) is a psychiatric disorder characterized by recurrent outbursts of aggressive behaviour. Deep brain stimulation (DBS) in the posteromedial nucleus of the hypothalamus (pHyp) is an alternative therapy for extreme cases and shows promising results. Intraoperative microdialysis can help elucidate the neurobiological mechanism of pHyp-DBS. Objective To evaluate efficacy and safety of pHyp-DBS using eight-contact directional leads in patients with refractory IED (rIED) and the accompanying changes in neurotransmitters. Methods A prospective study in which patients with a diagnosis of rIED were treated with pHyp-DBS for symptom alleviation. Bilateral pHyp-DBS was performed with eight-contact directional electrodes. Follow-up was performed at 3, 6 and 12 months after surgery. Results Four patients (3 men, mean age 27 ± 2.8 yr) were included. All patients were diagnosed with rIED and severe intellectual disability. Two patients had congenital rubella, one has co-diagnosis of infantile autism and the fourth presents with drug-resistant epilepsy. There was a marked increase in the levels of GABA and glycine during intraoperative stimulation. The average improvement in aggressive behaviour in the last follow-up was 6 points (Δ: 50%, p= 0.003) while also documenting an important improvement of the SF-36 in all domains except bodily pain. No adverse events associated with pHyp-DBS were observed. Conclusions This is the first study to show the safety and beneficial effect of directional lead pHyp-DBS in patients with refractory Intermittent Explosive Disorder and to demonstrate the corresponding mechanism of action through increases in GABA and glycine concentration in the pHyp.

Neurochemical effects of motor cortex stimulation in the periaqueductal gray during neuropathic pain

OBJECTIVE Motor cortex stimulation (MCS) is a neurosurgical technique used to treat patients with refractory neuropathic pain syndromes. MCS activates the periaqueductal gray (PAG) matter, which is one of the major centers of the descending pain inhibitory system. However, the neurochemical mechanisms in the PAG that underlie the analgesic effect of MCS have not yet been described. The main goal of this study was to investigate the neurochemical mechanisms involved in the analgesic effect induced by MCS in neuropathic pain. Specifically, we investigated the release of g-aminobutyric acid (GABA), glycine, and glutamate in the PAG and performed pharmacological antagonism experiments to validate of our findings. METHODS Male Wistar rats with surgically induced chronic constriction of the sciatic nerve, along with sham-operated rats and naive rats, were implanted with both unilateral transdural electrodes in the motor cortex and a microdialysis guide cannula in the PAG and subjected to MCS. The MCS was delivered in single 15-minute sessions. Neurotransmitter release was evaluated in the PAG before, during, and after MCS. Quantification of the neurotransmitters GABA, glycine, and glutamate was performed using a high-performance liquid chromatography system. The mechanical nociceptive threshold was evaluated initially, on the 14th day following the surgery, and during the MCS. In another group of neuropathic rats, once the analgesic effect after MCS was confirmed by the mechanical nociceptive test, rats were microinjected with saline or a glycine antagonist (strychnine), a GABA antagonist (bicuculline), or a combination of glycine and GABA antagonists (strychnine+bicuculline) and reevaluated for the mechanical nociceptive threshold during MCS. RESULTS MCS reversed the hyperalgesia induced by peripheral neuropathy in the rats with chronic sciatic nerve constriction and induced a significant increase in the glycine and GABA levels in the PAG in comparison with the naive and sham-treated rats. The glutamate levels remained stable under all conditions. The antagonism of glycine, GABA, and the combination of glycine and GABA reversed the MCS-induced analgesia. CONCLUSIONS These results suggest that the neurotransmitters glycine and GABA released in the PAG may be involved in the analgesia induced by cortical stimulation in animals with neuropathic pain. Further investigation of the mechanisms involved in MCS-induced analgesia may contribute to clinical improvements for the treatment of persistent neuropathic pain syndromes

Neurochemical effects of motor cortex stimulation in the periaqueductal gray during neuropathic pain

OBJECTIVE Motor cortex stimulation (MCS) is a neurosurgical technique used to treat patients with refractory neuropathic pain syndromes. MCS activates the periaqueductal gray (PAG) matter, which is one of the major centers of the descending pain inhibitory system. However, the neurochemical mechanisms in the PAG that underlie the analgesic effect of MCS have not yet been described. The main goal of this study was to investigate the neurochemical mechanisms involved in the analgesic effect induced by MCS in neuropathic pain. Specifically, we investigated the release of g-aminobutyric acid (GABA), glycine, and glutamate in the PAG and performed pharmacological antagonism experiments to validate of our findings. METHODS Male Wistar rats with surgically induced chronic constriction of the sciatic nerve, along with sham-operated rats and naive rats, were implanted with both unilateral transdural electrodes in the motor cortex and a microdialysis guide cannula in the PAG and subjected to MCS. The MCS was delivered in single 15-minute sessions. Neurotransmitter release was evaluated in the PAG before, during, and after MCS. Quantification of the neurotransmitters GABA, glycine, and glutamate was performed using a high-performance liquid chromatography system. The mechanical nociceptive threshold was evaluated initially, on the 14th day following the surgery, and during the MCS. In another group of neuropathic rats, once the analgesic effect after MCS was confirmed by the mechanical nociceptive test, rats were microinjected with saline or a glycine antagonist (strychnine), a GABA antagonist (bicuculline), or a combination of glycine and GABA antagonists (strychnine+bicuculline) and reevaluated for the mechanical nociceptive threshold during MCS. RESULTS MCS reversed the hyperalgesia induced by peripheral neuropathy in the rats with chronic sciatic nerve constriction and induced a significant increase in the glycine and GABA levels in the PAG in comparison with the naive and sham-treated rats. The glutamate levels remained stable under all conditions. The antagonism of glycine, GABA, and the combination of glycine and GABA reversed the MCS-induced analgesia. CONCLUSIONS These results suggest that the neurotransmitters glycine and GABA released in the PAG may be involved in the analgesia induced by cortical stimulation in animals with neuropathic pain. Further investigation of the mechanisms involved in MCS-induced analgesia may contribute to clinical improvements for the treatment of persistent neuropathic pain syndromes

Filhotes de escorpião T. serrulatus:: nascimento e desenvolvimento em cativeiro

A maioria dos escorpiões é ovovivípara, terminando seu desenvolvimento completo no dorso de sua mãe. Foi analisado o desenvolvimento dos filhotes de escorpião amarelo Tityus serrulatus Lutz & Melo, 1922 em cativeiro durante cinco meses no Biotério de Artrópodes do Instituto Butantan para compreender melhor seu crescimento. No decorrer do experimento foram retiradas 164 fêmeas que concederam 1.857 filhotes, mostrando como essa espécie de escorpião pode se multiplicar facilmente, em condições de laboratório. As fêmeas foram rastreadas através do seu viveiro e a quantidade de extrações sofridas, mostrando que as mesmas não foram afetadas pelas extrações em relação reprodução. O tempo estipulado para a dispersão dos juvenis foi de até 15 dias. Pode-se notar que o grupo que não sofreu qualquer extração, os recém-nascidos dispersaram espontaneamente coisa que não aconteceu para os outros grupos extraídos, tendo uma média de 4,95% para dispersão forçada. Conseguimos notar também que durante o trabalho realizado, o peso cresceu três vezes mais em relação ao peso inicial dos filhotes, e o crescimento foi de 1,5mm. Para o seu melhor desenvolvimento foi constatado que a alimentação três vezes na semana possui uma relevância notória.

Georreferenciamento das aranhas recebidas no Instituto Butantan (Loxosceles gaucho e Phoneutria nigriventer)

Os artrópodes correspondem a um grande grupo taxonômico, sendo encontrados na maioria dos habitats. A ordem Araneae possui uma morfologia de fácil identificação, é um grupo abundante contando hoje com 47.976 espécies incluídas em 117 famílias no mundo. Algumas espécies como Loxosceles gaucho e Phoneutria nigriventer são consideradas de grande importância médica, só no ano de 2017 foram notificados aproximadamente 5.000 casos de araneísmo no estado de São Paulo. Realizou-se o georreferenciamento da entrada de aranhas das espécies Phoneutria nigriventer e Loxosceles gaucho da recepção de animais do Instituto Butantan no período de 2013 a 2017, restrito ao Estado de São Paulo. Foi analisada a quantidade de animais entregues através da demanda espontânea (DE) e quantidade de animais coletados pelo Laboratório de Artrópodes (LA). Foram registradas 103.290 entradas de aranhas da espécie L. gaúcho, destes registros, 102.429 (99%) foram provenientes de coletas realizadas pelo Laboratório de Artrópodes e 871 (1%) referentes às entregas espontâneas. Com 4.195 entradas de aranhas da espécie P. nigriventer, 1.537 (36,63%) foram provenientes de coletas realizadas pelo Laboratório de Artrópodes, e 2.659 (63,37%) referentes às entregas espontâneas. Novos locais podem ser pontos significativos de coleta do Laboratório de Artrópodes, sendo necessário avaliar a quantidade e as regiões tanto dos animais que são provenientes das coletas do laboratório como também da demanda espontânea que dão entrada na recepção de animais do Instituto Butantan.

Análise dos índices de criação e manutenção de escorpiôes do laboratório de artrópodes

O biotério de artrópodes cria e mantém espécies de escorpiões desde sua inauguração em março de 1995, onde, ao longo deste período foram estudadas as melhores maneiras para otimizar a criação e manutenção dos animais recebidos e criados, aprimorando a técnica de bioterismo para estes animais. Os objetivos do presente estudo foram apresentar dados referentes a manutenção em cativeiro de T. serrulatus no laboratório de artrópodes de 2014 á 2018, de modo a contribuir com dados a cerca do bioterismo desta espécie, e assim é possível observar que o número de animais aumenta ao longo dos anos, consequentemente o número de extrações de veneno, e a taxa de mortalidade cai, provavelmente devido ao número de acidentes que vem aumentando com esta espécie, associado á sua rápida proliferação.

Influence of different processing techniques on the toxicity and biochemical characteristics of Tityus serrulatus scorpion venom.

Studies of scorpion venoms have used different venom drying methods: lyophilization, desiccation, lyophilization after mixing with 0.9% saline or purified water and centrifugation. The aim of this study was to see if these different approaches cause some alteration in the composition of the venom or interfere with its biological effects. Mice were injected (i.p.) with T. serrulatus scorpion venom in the liquid form (G-liq) or dried by different methods (lyophilized - G-lyo; centrifuged and the supernatant lyophilized - G-cen; desiccated - G-des), and observed regarding the occurrence of the symptoms respiratory difficulty, convulsion and death. The occurrence of seizures, although occurring in all groups and with the various doses used, did not prove to be effective to determine differences between the different handling techniques. Respiratory distress appeared to be useful in analyzing differences between groups, where this effect was less pronounced in the G-liq and G-des groups. In general, death occurred in a certain proportion with increasing dose for all groups. G-liq and G-des seemed to be more "active" at lower doses and G-cen and G-lyo at higher doses. The electrophoretic and chromatographic profile demonstrated main differences between G-liq and the dried groups. In the electrophoretic profile, the liquid venom showed bands of proteins of higher concentration and greater number of major bands and the three dried venom had the lowest number of protein bands. The HPLC profile and densitometry of the electrophoretic profiles showed some differences that may be associated with different protein conformation/aggregation. Our data indicated that lyophilization is the most suitable method for processing T. serrulatus scorpion venom after extraction.

Influence of different processing techniques on the toxicity and biochemical characteristics of Tityus serrulatus scorpion venom

Studies of scorpion venoms have used different venom drying methods: lyophilization, desiccation, lyophilization after mixing with 0.9% saline or purified water and centrifugation. The aim of this study was to see if these different approaches cause some alteration in the composition of the venom or interfere with its biological effects. Mice were injected (i.p.) with T. serrulatus scorpion venom in the liquid form (G-liq) or dried by different methods (lyophilized – G-lyo; centrifuged and the supernatant lyophilized – G-cen; desiccated – G-des), and observed regarding the occurrence of the symptoms respiratory difficulty, convulsion and death. The occurrence of seizures, although occurring in all groups and with the various doses used, did not prove to be effective to determine differences between the different handling techniques. Respiratory distress appeared to be useful in analyzing differences between groups, where this effect was less pronounced in the G-liq and G-des groups. In general, death occurred in a certain proportion with increasing dose for all groups. G-liq and G-des seemed to be more "active" at lower doses and G-cen and G-lyo at higher doses. The electrophoretic and chromatographic profile demonstrated main differences between G-liq and the dried groups. In the electrophoretic profile, the liquid venom showed bands of proteins of higher concentration and greater number of major bands and the three dried venom had the lowest number of protein bands. The HPLC profile and densitometry of the electrophoretic profiles showed some differences that may be associated with different protein conformation/aggregation. Our data indicated that lyophilization is the most suitable method for processing T. serrulatus scorpion venom after extraction.

Influence of different processing techniques on the toxicity and biochemical characteristics of Tityus serrulatus scorpion venom

Studies of scorpion venoms have used different venom drying methods: lyophilization, desiccation, lyophilization after mixing with 0.9% saline or purified water and centrifugation. The aim of this study was to see if these different approaches cause some alteration in the composition of the venom or interfere with its biological effects. Mice were injected (i.p.) with T. serrulatus scorpion venom in the liquid form (G-liq) or dried by different methods (lyophilized – G-lyo; centrifuged and the supernatant lyophilized – G-cen; desiccated – G-des), and observed regarding the occurrence of the symptoms respiratory difficulty, convulsion and death. The occurrence of seizures, although occurring in all groups and with the various doses used, did not prove to be effective to determine differences between the different handling techniques. Respiratory distress appeared to be useful in analyzing differences between groups, where this effect was less pronounced in the G-liq and G-des groups. In general, death occurred in a certain proportion with increasing dose for all groups. G-liq and G-des seemed to be more "active" at lower doses and G-cen and G-lyo at higher doses. The electrophoretic and chromatographic profile demonstrated main differences between G-liq and the dried groups. In the electrophoretic profile, the liquid venom showed bands of proteins of higher concentration and greater number of major bands and the three dried venom had the lowest number of protein bands. The HPLC profile and densitometry of the electrophoretic profiles showed some differences that may be associated with different protein conformation/aggregation. Our data indicated that lyophilization is the most suitable method for processing T. serrulatus scorpion venom after extraction.

Stinging caterpillars from the genera Podalia, Leucanella and Lonomia in Misiones, Argentina: A preliminary comparative approach to understand their toxicity.

Dermal contact with Lepidoptera specimens at their larval stage (caterpillar) may cause systemic and/or local envenomation. There are multiple venomous species of them in Argentina, but their overall venom composition is poorly known. Lately, several cases of envenomation have been reported in the Misiones province, Northeastern Argentina. Thus, this work aimed to compare the protein composition, and the enzymatic properties of bristle extracts from caterpillars belonging to the families Megalopygidae (Podalia ca. fuscescens) and Saturniidae (Leucanella memusae and Lonomia obliqua) - the most common causative agents of accidents in Misiones -, and additionally to test their cross-reactivity with the L. obliqua antivenom produced in Brazil. Saturniidae venoms exhibited striking similarity in both their electrophoretic protein profile, and antigenic cross-reactivity. All venoms degraded azocasein - with the highest proteolytic activity observed in the P. ca. fuscescens bristle extract -, and hyaluronic acid, but the latter at low levels. Lonomia obliqua venom exhibited the highest level of phospholipase A2 activity. Bristle extracts from P. ca. fuscescens and L. obliqua both degraded human fibrin(ogen) and shortened the clotting time triggered by calcium, while L. memusae venom inhibited plasma coagulation. Proteins related to the coagulation disturbance were identified by mass spectrometry in all samples. Altogether, our findings show for the first time a comparative biotoxinological analysis of three genera of caterpillars with medical relevance. Moreover, this study provides relevant information about the pathophysiological mechanisms whereby these caterpillar bristle extracts can induce toxicity on human beings, and gives insight into future directions for research on them.

Ivermectin reduces motor coordination, serum testosterone, and central neurotransmitter levels but does not affect sexual motivation in male rats

Ivermectin (IVM) is a macrocyclic lactone used for the treatment of parasitic infections and widely used in veterinary medicine as endectocide. In mammals, evidence indicates that IVM interacts with ?-aminobutyric acid (GABA)-mediated chloride channels. GABAergic system is involved in the manifestation of sexual behavior. We previously found that IVM at therapeutic doses did not alter sexual behavior in male rats, but at a higher dose, the appetitive phase of sexual behavior was impaired. Thus, we investigated whether the reduction of sexual behavior that was previously observed was a consequence of motor or motivational deficits that are induced by IVM. Data showed significant decrease in striatal dopaminergic system activity and lower testosterone levels but no effects on sexual motivation or penile erection. These findings suggest IVM may activate the GABAergic system and reduce testosterone levels, resulting in a reduction of motor coordination as consequence of the inhibition of striatal dopamine release.

Cytotoxic effects of dillapiole on MDA-MB-231 cells involve the induction of apoptosis through the mitochondrial pathway by inducing an oxidative stress while altering the cytoskeleton network.

Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Here, we have demonstrated for the first time that dillapiole has broad cytotoxic effects against a variety tumor cells. For instance, we found that it can act as a pro-oxidant compound through the induction of reactive oxygen species (ROS) release in MDA-MB-231 cells. We also demonstrated that dillapiole exhibits anti-proliferative properties, arresting cells at the G0/G1 phase and its antimigration effects can be associated with the disruption of actin filaments, which in turn can prevent tumor cell proliferation. Molecular modeling studies corroborated the biological findings and suggested that dillapiole may present a good pharmacokinetic profile, mainly because its hydrophobic character, which can facilitate its diffusion through tumor cell membranes. All these findings support the fact that dillapiole is a promising anticancer agent.

Dillapiole as antileishmanial agent: discovery, cytotoxic activity and preliminary SAR studies of dillapiole analogues.

In this paper, the isolation of dillapiole (1) from Piper aduncum was reported as well as the semi-synthesis of two phenylpropanoid derivatives [di-hydrodillapiole (2), isodillapiole (3)], via reduction and isomerization reactions. Also, the compounds' molecular properties (structural, electronic, hydrophobic, and steric) were calculated and investigated to establish some preliminary structure-activity relationships (SAR). Compounds were evaluated for in vitro antileishmanial activity and cytotoxic effects on fibroblast cells. Compound 1 presented inhibitory activity against Leishmania amazonensis (IC(50) = 69.3 µM) and Leishmania brasiliensis (IC(50) = 59.4 µM) and induced cytotoxic effects on fibroblast cells mainly in high concentrations. Compounds 2 (IC(50) = 99.9 µM for L. amazonensis and IC(50) = 90.5 µM for L. braziliensis) and 3 (IC(50) = 122.9 µM for L. amazonensis and IC(50) = 109.8 µM for L. brasiliensis) were less active than dillapiole (1). Regarding the molecular properties, the conformational arrangement of the side chain, electronic features, and the hydrophilic/hydrophobic balance seem to be relevant for explaining the antileishmanial activity of dillapiole and its analogues.