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The calyxes of Hibiscus sabdariffa present multiple pharmacological effects primarily attributed to their high anthocyanin content; however, little is known about their phytoestrogenic effect. Ovarian hypofunction (OH) is a process characterized by the rapid detention of the production of ovarian hormones, which compromises reproductive and cognitive functions. Hormone replacement therapy (HRT) efficiently compensates for OH; nevertheless, questions have been raised on its secondary effects and safety. One of the alternatives to tackling OH involves using phytoestrogens such as anthocyanins for their structural similarity to natural estrogens. In a Wistar rat model of ovariectomy (OVX), we recently reported the beneficial properties of an anthocyanin-rich extract prepared from the calyces of H. sabdariffa (HSE) in hindering the adverse effects of OH on memory performance and highlighted a possible phytoestrogenic impact through the modulation of estrogen receptor (ER) expression. We now report that HSE and estradiol differentially affected the expression of ERα and ERß. ERα was more sensitive to HSE; meanwhile, estradiol preferentially modulated ERß. Thus, our study leads to further research on using H. sabdariffa as a nutrition-based alternative to HRT.

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Background: Cognition and brain function is critical through childhood and should be improved with balanced diets. Incorporating bioactive ingredients such as omega-3 polyunsaturated fatty acids (ω3 PUFAs) and probiotics into food formulations could be used as an approach to improve cognitive function. This study evaluated the effects on cognitive capacity of complementing rodent diets with chocolate, by itself and in combination with ω3 PUFAs from fish oil and probiotics. Methods: Spatial learning and memory in the rats were determined by the Barnes maze test in short- and long-term memory. Samples from the cecum were obtained to assess microbial counts (Lactobacillus, Bifidobacterium, Enterobacteriaceae, and total bacteria), and brains were recovered to analyze the neural morphology of the tissues. Also, glucose, brain weights, and epididymal tissue were analyzed. Results: The combination of chocolate with fish oil and probiotics improved the memory of rats compared to the result of each bioactive compound when evaluated separately. Treatments did not affect sugar level, epididymal adipose tissue, or brain weight. On the other hand, consuming probiotics alone or in combination with chocolate decreased Enterobacteria counts, while Lactobacillus and Bifidobacteria counts were not affected. Neural morphological analysis showed that combining chocolate with probiotics and ω3 PUFAs increased the number of neurons in the hippocampal CA1 and CA3 regions. Conclusion: Chocolate added with probiotics and ω3 PUFAs improved spatial memory and learning in the studied model.

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Several pathophysiological processes involve Hypoxia conditions, where the nervous system is affected as well. We postulate that the GABAergic system is especially sensitive. Furthermore, drugs improving the resistance to hypoxia have been investigated, such as the neurosteroid dehydroepiandrosterone sulfate (DHEAS) which has shown beneficial effects in hypoxic processes in mammals; however, at the cellular level, its exact mechanism of action has yet to be fully elucidated. Here, we used a chemical hypoxia model through sodium sulfite (SS) exposure in Caenorhabditis elegans (C. elegans), a nematode whose response to hypoxia involves pathways and cellular processes conserved in mammals, and that allows study the direct effect of DHEAS without its conversion to sex hormones. This work aimed to determine the effect of DHEAS on damage to the GABAergic system associated with SS exposure in C. elegans. Worms were subjected to nose touch response (Not Assay) and observed in epifluorescence microscopy. DHEAS decreased the shrinkage response of Not Assay and the level of damage in GABAergic neurons on SS-exposed worms. Also, the enhanced nuclear localization of DAF-16 and consequently the overexpression of chaperone HSP-16.2 by hypoxia were significantly reduced in SS + DHEAS exposed worms. As well, DHEAS increased the survival rate of worms exposed to hydrogen peroxide. These results suggest that hypoxia-caused damage over the GABAergic system was prevented at least partially by DHEAS, probably through non-genomic mechanisms that involve its antioxidant properties related to its chemical structure.

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As a source of bioactive compounds, species of the genus Lupinus are interesting legumes from a nutritional point of view. Although wild species are abundant and represent a potential source of nutrients and biologically active compounds, most research has focused on domesticated and semi-domesticated species, such as Lupinus angustifolius, Lupinus albus, Lupinus luteus, and Lupinus mutabilis. Therefore, in this review, we focus on recent research conducted on the wild Lupinus species of Mexico. The nutritional content of these species is characterized (similar to those of the domesticated species), including proteins (isolates), lipids, minerals, dietary fiber, and bioactive compounds, such as oligosaccharides, flavonoids, and alkaloids.

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Theileria equi infection prevalence was calculated from 1000 blood samples obtained from apparently healthy horses in western Mexico. Samples were sent to the Animal Biotechnology Laboratory of the University of Guadalajara (Mexico) for T. equi diagnosis. Nested polymerase chain reaction (nPCR) was used as a diagnostic method to detect pathogen DNA. Using primers for the merozoite antigen-1 (EMA-1) gene, 19.70±2.47% of the horses (95% CI, 17.23-22.17%) tested positive for T. equi. There was no significant association between gender and T. equi infection. However, prevalence was higher among stabled horses (25.81%) than that among grazing horses (15.02%). The positivity rate was also higher among Quarter Horse (24.70%), Lusitano (35.90%), and Costa Rican Saddle Horse (47.37%) breeds than that among the other seven breeds investigated in this study. The percentage of T. equi infection was higher among adult horses (≥ 4years old, 25.05%) than that among colts and fillies (2-4years old, 15.48%), yearlings (1-2years old, 10.49%), and foals (<1year old, 10.34%). This is the first study of T. equi infection prevalence among horses in Mexico by nPCR . The results indicate that the equine piroplasmosis (EP) caused by T. equi is enzootic in western Mexico.

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Sparteine is one of the most toxic quinolizidine alkaloids found in leguminous plants. Several studies have demonstrated that sparteine affects the nervous system, blocking the nervous ganglion, producing antimuscarinic effects, depressing the central nervous system and causing neuronal necrosis. However, there are no reports identifying the areas of the brain that are sensitive to the toxic effects of this alkaloid. 32 adult Wistar rats were on study, sixteen were implanted with an intracerebral stainless steel cannula and randomly assigned to a control or experimental group (n=8). Animals, control and experimental, received daily intraventricular (ICV) injections of a sparteine or a sterile water solution for five consecutive days. Additionally, two groups of animals (8 rats each) received daily intraperotineal injections (IP) of a sparteine or sterile water solution for five consecutive days. 72h after the last dose, the animals were sacrificed, their brains removed, fixed and embedded in paraffin to obtain 10µm tissue slices. Brain slices were stained with H&E and evaluated under a light microscope. The main brain structures sensitive to sparteine were the cerebral cortex (frontal, fronto-parietal and striate) olfactory and amygdaloid areas, the ventromedial hypothalamic nucleus, the Purkinje cells in the cerebellum, and the CA1, CA3 and dentate gyrus regions of the hippocampus. Administration of sparteine, via ICV or IP, caused neuronal necrosis in brain structures, mainly related with cholinergic pathways.

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We performed experiments in cats with a spinal cord penetrating hemisection at T13-L1 level, with and without tamoxifen treatment. The results showed that the numbers of the ipsilateral and contralateral ventral horn neurons were reduced to less than half in the nontreated animals compared with the treated ones. Also, axons myelin sheet was preserved to almost normal values in treated cats. On the contrary, in the untreated animals, their myelin sheet was reduced to 28% at 30 days after injury (DAI), in both the ipsilateral and contralateral regions of the spinal cord. Additionally, we made hindlimb kinematics experiments to study the effects of tamoxifen on cat locomotion after the injury: at 4, 16, and 30 DAI. We observed that the ipsilateral hindlimb angular displacement (AD) of the pendulum-like movements (PLM) during gait locomotion was recovered to almost normal values in treated cats. Contralateral PLM acquired similar values to those obtained in intact cats. At 4 DAI, untreated animals showed a compensatory increment of PLM occurring in the contralateral hindlimb, which was partially recovered at 30 DAI. Our findings indicate that tamoxifen exerts a neuroprotective effect and preserves or produces myelinated axons, which could benefit the locomotion recovery in injured cats.

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The aim of this study was to determine the flavonoid profile of Lupinus mexicanus germinated seed extract (PE) and to evaluate its effect as a phytoestrogen on the morphometric parameters of CA3 hippocampal neurons of ovariectomized rats (OVX). L. mexicanus seeds, germinated for 48 h, were homogenized and macerated using an 80% ethanol solution. The extract was analyzed by HPLC/MS-MS. Thirty young Wistar strain female rats (200±10 g) were randomly distributed into four groups: sham operated (S) treated with dimethyl sulfoxide (vehicle); ovariectomized and treated with 1250 µg of PE extract (OVX-PE); ovariectomized and treated with 5 µg estradiol benzoate (OVX-EB); and ovariectomized and vehicle treated (OVX). All substances were injected subcutaneously daily for 28 days. On day 29, the animals were sacrificed, perfused, and fixed to obtain the brains for histological processing. Each brain was cut and stained with hematoxylin and eosin. The thickness of the stratum oriens (SO), the nuclear diameter, and the neuronal density were measured in the hippocampus CA3 area. Nine different flavonoids and one non-identified compound were detected. The histological analysis demonstrated that the thickness of the SO was higher in the OVX-EB and S groups than in the OVX-PE and OVX groups (p⟨0.05); in addition, the nuclear diameters of the neurons in the OVX-EB and S groups were higher compared with the other groups (p⟨0.05). The OVX group had the highest cellular density among groups (p⟨0.05). Based on our results, the PE obtained did not have beneficial effects on CA3 hippocampal neurons.

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Systemic administration of kainic acid (KA) in rodents triggers limbic seizures following selective neuronal loss in the hippocampus attributed to the excitotoxic process. Lipid peroxidation products, such as 4-hydroxynonenal, are produced by oxidative stress and are present on the hippocampus, which contribute to neuronal death in the KA excitotoxicity model. Several antioxidants are neuroprotective agents. The aim of the present study was to analyse whether pirfenidone (PFD, 5-methyl-1-phenyl-2-(1H)-pyridone), an antioxidant drug, protects the neurons in the hippocampus of pubescent rats administered with KA. We evaluated the neuroprotective effect of PFD by quantifying the surviving neurons under hematoxilin-eosin staining after using three different doses of 100, 250, and 325 mg/kg administered via an orogastric tube 90 min after KA intraperitoneal injection (12 mg/kg). Only 325 mg/kg of PFD-attenuated neuronal loss in the hippocampal areas cornu ammonis field 1 (CA1) and cornu ammonis field 3 (CA3c) was observed; therefore, this dose was used in our subsequent studies. Later, we established that PFD reduces neuronal degeneration using Fluoro-Jade B stain in the CA3c but not in the CA1, and PFD reduces the presence of 4-hydroxynonenal, a lipid peroxidation product, in the CA3 by tissue immunohistochemistry. We concluded that only a single 325 mg/kg PFD dose had a neuroprotective effect after KA brain injury. This treatment may be advantageous because adequate pharmacological therapy with PFD can be developed to protect the neuron even after an acute neuronal disorder such as seizures or hypoxic/ischemic damage.

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It has been demonstrated that the exposure of biological systems to magnetic fields (MFs) can produce several beneficial effects: tissue recovery in chronic wounds, re-establishment of blood circulation after tissue ischemia or in necrotic tissues, improvement after epileptic episodes, angiogenesis, etc. In the current study, the effects of extremely low frequency (ELF) MF on the capillaries of some circumventricular organs (CVOs) are demonstrated; a vasodilator effect is reported as well as an increase in their permeability to non-liposoluble substances. For this study, 96 Wistar male rats (250 g body mass) were used and divided into three groups of 32 rats each: a control group (no treatment); a sham ELF-MF group; and an experimental group subjected to ELF-MF (120 Hz harmonic waves and 0.66 mT, root mean square) by the use of Helmholtz coils. All animals were administered colloidal carbon (CC) intravenously to study, through optical and transmission electron microscopy, the capillary permeability in CVOs and the blood-brain barrier (BBB) in brain areas. An increase in capillary permeability to CC was detected in the ELF-MF-exposed group as well as a significant increase in vascular area (capillary vasodilation); none of these effects were observed in individuals of the control and sham ELF-MF groups. It is important to investigate the mechanisms involved in the phenomena reported here in order to explain the effects of ELF-MF on brain vasculature.

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