Inhaled Litsea glaucescens K. (Lauraceae) leaves' essential oil has anxiolytic and antidepressant-like activity in mice by BDNF pathway activation

ETHNOPHARMACOLOGICAL RELEVANCE

Litsea glaucescens K. (Lauraceae) is a small tree from the Mexican and Central American temperate forests, named as "Laurel". Its aromatic leaves are ordinarily consumed as condiments, but also are important in Mexican Traditional Medicine, and among the most important non wood forest products in this area. The leaves are currently used in a decoction for the relief of sadness by the Mazahua ethnic group. Interestingly, "Laurel" has a long history. It was named as "Ehecapahtli" (wind medicine) in pre-Columbian times and applied to heal maladies correlated to the Central Nervous System, among them depression, according to botanical texts written in the American Continent almost five centuries ago.

AIM OF THE STUDY

Depression is the first cause of incapacity in the world, and society demands alternative treatments, including aromatherapy. We have previously demonstrated the antidepressant-like activity of L. glaucescens leaves' essential oil (LEO), as well as their monoterpenes linalool, and beta-pinene by intraperitoneal route in a mice behavioral model. Here we now examined if LEO and linalool exhibit this property and anxiolytic activity when administered to mice by inhalation. We also investigated if these effects occur by BDNF pathway activation in the brain.

MATERIALS AND METHODS

The LEO was prepared by distillation with water steam and analyzed by gas chromatography-mass spectrometry (GC-MS). The monoterpenes linalool, eucalyptol and β-pinene were identified and quantified. Antidepressant type properties were determined with the Forced Swim Test (FST) on mice previously exposed to LEO or linalool in an inhalation chamber. The spontaneous locomotor activity and the sedative effect were assessed with the Open Field Test (OFT), and the Exploratory Cylinder (EC), respectively. The anxiolytic properties were investigated with the Elevated Plus Maze Apparatus (EPM) and the Hole Board Test (HBT). All experiments were video documented. The mice were subjected to euthanasia, and the brain hippocampus and prefrontal cortex were dissected.

RESULTS

The L. glaucescens essential oil (LEO) contains 31 compounds according to GC/MS, including eucalyptol, linalool and beta-pinene. The LEO has anxiolytic effect by inhalation in mice, as well as linalool, and β-pinene, as indicated by OFT and EC tests. The LEO and imipramine have antidepressant like activity in mice as revealed by the FST; however, linalool and ketamine treatments didn't modify the time of immobility. The BDNF was increased in FST in mice treated with LEO in both areas of the brain as revealed by Western blot; but did not decrease the level of corticosterone in plasma. The OFT indicated that LEO and imipramine didn't reduce the spontaneous motor activity, while linalool and ketamine caused a significant decrease.

CONCLUSION

Here we report by the first time that L. glaucescens leaves essential oil has anxiolytic effect by inhalation in mice, as well as linalool, and β-pinene. This oil also maintains its antidepressant-like activity by this administration way, similarly to the previously determined intraperitoneally. Since inhalation is a common administration route for humans, our results suggest L. glaucescens essential oil deserve future investigation due to its potential application in aromatherapy.

GrimAge is elevated in older adults with mild COVID-19 an exploratory analysis

COVID-19 has been contained; however, the side effects associated with its infection continue to be a challenge for public health, particularly for older adults. On the other hand, epigenetic status contributes to the inter-individual health status and is associated with COVID-19 severity. Nevertheless, current studies focus only on severe COVID-19. Considering that most of the worldwide population developed mild COVID-19 infection. In the present exploratory study, we aim to analyze the association of mild COVID-19 with epigenetic ages (HorvathAge, HannumAge, GrimAge, PhenoAge, SkinAge, and DNAmTL) and clinical variables obtained from a Mexican cohort of older adults. We found that all epigenetic ages significantly differ from the chronological age, but only GrimAge is elevated. Additionally, both the intrinsic epigenetic age acceleration (IEAA) and the extrinsic epigenetic age acceleration (EEAA) are accelerated in all patients. Moreover, we found that immunological estimators and DNA damage were associated with PhenoAge, SkinBloodHorvathAge, and HorvathAge, suggesting that the effects of mild COVID-19 on the epigenetic clocks are mainly associated with inflammation and immunology changes. In conclusion, our results show that the effects of mild COVID-19 on the epigenetic clock are mainly associated with the immune system and an increase in GrimAge, IEAA, and EEAA.

Unraveling the Neuroprotective Effect of Natural Bioactive Compounds Involved in the Modulation of Ischemic Stroke by Network Pharmacology

Ischemic stroke (IS) is one of the leading causes of mortality worldwide. It is characterized by the partial or total occlusion of arteries that supply blood to the brain, leading to the death of brain cells. In recent years, natural bioactive compounds (NBCs) have shown properties that ameliorate the injury after IS and improve the patient's outcome, which has proven to be a potential therapeutic strategy due to their neuroprotective effects. Hence, in the present study, we use both systems pharmacology and chemoinformatic analyses to identify which NBCs have the most potential to be used against IS in clinics. Our results identify that flavonoids and terpenoids are the most studied NBCs, and, mainly, salidrosides, ginkgolides A, B, C, and K, cordycepin, curcumin, baicalin, resveratrol, fucose, and cannabidiol, target the main pathological processes occurring in IS. However, the medicinal chemistry properties of such compounds demonstrate that only six fulfill such criteria. However, only cordycepin and salidroside possess properties as leader molecules, suggesting that these compounds may be considered in developing novel drugs against IS.

Insomnia Impairs Both the Pro-BDNF and the BDNF Levels Similarly to Older Adults with Cognitive Decline: An Exploratory Study

Sleep disorders, including insomnia, are common during aging, and these conditions have been associated with cognitive decline in older adults. Moreover, during the aging process, neurotransmitters, neurohormones, and neurotrophins decrease significantly, leading to the impairment of cognitive functions. In this sense, BDNF, the most abundant neurotrophic factor in the human brain, has been suggested as a potential target for the prevention and improvement of cognitive decline during aging; however, the current evidence demonstrates that the exogenous administration of BDNF does not improve cognitive function. Hence, in the present study, we quantified pro-BDNF (inactive) and BDNF (active) concentrations in serum samples derived from older individuals with insomnia and/or cognitive decline. We used linear regression to analyze whether clinical or sociodemographic variables impacted the levels of BNDF concentration. We observed that insomnia, rather than cognitive decline, is significantly associated with BDNF concentration, and these effects are independent of other variables. To our knowledge, this is the first study that points to the impact of insomnia on improving the levels of BDNF during aging and suggests that opportune treatment of insomnia may be more beneficial to prevent cognitive decline during aging.

Structural and Pharmacological Network Analysis of miRNAs Involved in Acute Ischemic Stroke: A Systematic Review

Acute ischemic stroke (AIS) is among the main causes of mortality worldwide. A rapid and opportune diagnosis is crucial to improve a patient’s outcomes; despite the current advanced image technologies for diagnosis, their implementation is challenging. MicroRNAs have been recognized as useful as biomarkers since they are specific and stable for characterization of AIS. However, there is still a lack of consensus over the primary miRNAs implicated in AIS. Here, we performed a systematic review of the literature covering from 2015–2021 regarding miRNAs expression during AIS and built structural networks to analyze and identify the most common miRNAs expressed during AIS and shared pathways, genes, and compounds that seem to influence their expression. We identified two sets of miRNAs: on one side, a set that was independent of geographical location and tissue (miR-124, miR-107, miR-221, miR-223, miR-140, miR-151a, miR-181a, miR-320b, and miR-484); and on the other side, a set that was connected (hubs) in biological networks (miR-27b-3p, miR-26b-5p, miR-124-3p, miR-570-3p, miR-19a-3p, miR-101-3p and miR-25-3p), which altered FOXO3, FOXO4, and EP300 genes. Interestingly, such genes are involved in cell death, FOXO-mediated transcription, and brain-derived neurotrophic factor signaling pathways. Finally, our pharmacological network analysis depicted a set of toxicants and drugs related to AIS for the first time.

Senescence in Primary Rat Astrocytes Induces Loss of the Mitochondrial Membrane Potential and Alters Mitochondrial Dynamics in Cortical Neurons

The decline in brain function during aging is one of the most critical health problems nowadays. Although senescent astrocytes have been found in old-age brains and neurodegenerative diseases, their impact on the function of other cerebral cell types is unknown. The aim of this study was to evaluate the effect of senescent astrocytes on the mitochondrial function of a neuron. In order to evaluate neuronal susceptibility to a long and constant senescence-associated secretory phenotype (SASP) exposure, we developed a model by using cellular cocultures in transwell plates. Rat primary cortical astrocytes were seeded in transwell inserts and induced to premature senescence with hydrogen peroxide [stress-induced premature senescence (SIPS)]. Independently, primary rat cortical neurons were seeded at the bottom of transwells. After neuronal 6 days in vitro (DIV), the inserts with SIPS-astrocytes were placed in the chamber and cocultured with neurons for 6 more days. The neuronal viability, the redox state [reduced glutathione/oxidized glutathione (GSH/GSSG)], the mitochondrial morphology, and the proteins and membrane potential were determined. Our results showed that the neuronal mitochondria functionality was altered after being cocultured with senescent astrocytes. In vivo, we found that old animals had diminished mitochondrial oxidative phosphorylation (OXPHOS) proteins, redox state, and senescence markers as compared to young rats, suggesting effects of the senescent astrocytes similar to the ones we observed in vitro. Overall, these results indicate that the microenvironment generated by senescent astrocytes can affect neuronal mitochondria and physiology.

Promising biomarkers of human aging: In search of a multi-omics panel to understand the aging process from a multidimensional perspective

The aging process has been linked to the occurrence of chronic diseases and functional impairments, including cancer, sarcopenia, frailty, metabolic, cardiovascular, and neurodegenerative diseases. Nonetheless, aging is highly variable and heterogeneous and represents a challenge for its characterization. In this sense, intrinsic capacity (IC) stands as a novel perspective by the World Health Organization, which integrates the individual wellbeing, environment, and risk factors to understand aging. However, there is a lack of quantitative and qualitative attributes to define it objectively. Therefore, in this review we attempt to summarize the most relevant and promising biomarkers described in clinical studies at date over different molecular levels, including epigenomics, transcriptomics, proteomics, metabolomics, and the microbiome. To aid gerontologists, geriatricians, and biomedical researchers to understand the aging process through the IC. Aging biomarkers reflect the physiological state of individuals and the underlying mechanisms related to homeostatic changes throughout an individual lifespan; they demonstrated that aging could be measured independently of time (that may explain its heterogeneity) and to be helpful to predict age-related syndromes and mortality. In summary, we highlight the areas of opportunity and gaps of knowledge that must be addressed to fully integrate biomedical findings into clinically useful tools and interventions.

Transcriptomic analysis reveals new hippocampal gene networks induced by prolactin

Prolactin (Prl) is a pleiotropic hormone with multiple functions in several tissues and organs, including the brain. In the hippocampus, Prl has been implicated in several functions, including neuroprotection against excitotoxicity in lactating rats and in Prl-treated ovariectomized animals. However, the molecular mechanisms involved in Prl actions in the hippocampus have not been completely elucidated. The aim of this study was to analyse the hippocampal transcriptome of female Prl-treated ovariectomized rats. Transcriptomic analysis by RNASeq revealed 162 differentially expressed genes throughout 24 h of Prl treatment. Gene Ontology analysis of those genes showed that 37.65% were involved in brain processes that are regulated by the hippocampus, such as learning, memory and behaviour, as well as new processes that we did not foresee, such as glial differentiation, axogenesis, synaptic transmission, postsynaptic potential, and neuronal and glial migration. Immunodetection analysis demonstrated that Prl significantly modified microglial morphology, reduced the expression of Cd11b/c protein, and altered the content and location of the neuronal proteins Tau, Map2 and Syp, which are involved in axogenic and synaptic functions. This novel delineation of Prl activity in the hippocampus highlights its importance as a neuroactive hormone, opens a new avenue for understanding its actions and supports its participation in neuronal plasticity of this brain area.

Network Pharmacology Uncovers Anticancer Activity of Mammea-Type Coumarins from Calophyllum brasiliense

Mammea-type coumarins are a particular type of secondary metabolites biosynthesized by the tropical rainforest tree Calophyllum Brasiliense, which is distributed from South America to Mexico. Particularly, mammea A/BA and A/BB (alone or as a mixture) possess biological properties such as cytotoxic and antitumoral activities, however, most of its molecular targets remain unknown. In this context, novel bioinformatic approaches, such as network pharmacology analysis, have been successfully used in herbal medicine to accelerate research in this field, and the support of experimental validations has been shown to be quite robust. In the present study, we performed a network pharmacology analysis to assess the possible molecular biological networks that interact with mammea A/BA and A/BB. Moreover, we validated the most relevant networks experimentally in vitro on K562 cancer cells. The results of the network pharmacology analysis indicate that mammea A/BA and A/BB interacts with cell death, PI3K/AKT, MAPK, Ras, and cancer pathways. The in vitro model shows that mammea A/BA and A/BB induce apoptosis through the overexpression of the proapoptotic proteins Bax and Bak, disrupt the autophagic flux as seen by the cytosolic accumulation of LC3-II and p62, disrupting the mitochondria ultrastructure and concomitantly increase the intracellular calcium concentration. Additionally, docking analysis predicted a possible interaction with a rapamycin-binding domain of mTOR. In conclusion, we validated network pharmacology analysis and report, for the first time, that mammea A/BA and A/BB coumarins induce apoptosis through the inhibition of the autophagic flux, possibly interacting with mTOR.

Prolactin function and putative expression in the brain

INTRODUCTION

Prolactin is a peptide hormone mainly synthetized and secreted by the anterior pituitary gland, but also by extrapituitary tissues, such as mammary gland, decidua, prostate, skin, and possibly the brain. Similarly, prolactin receptor is expressed in the pituitary gland, many peripheral tissues, and in contrast to prolactin, its receptor has been consistently detected in several brain regions, such as cerebral cortex, olfactory bulb, hypothalamus, hippocampus, amygdala, among others. Classically, prolactin function has been related to the stimulation of lactogenesis and galactopoiesis, however, it is well known that prolactin induces a wide range of functions in different brain areas.

PURPOSE

The aim of this review is to summarize recent reports on prolactin and prolactin receptor synthesis and localization, as well as recapitulate both the classic functions attributed to this hormone in the brain and the recently described functions such as neurogenesis, neurodevelopment, sleep, learning and memory, and neuroprotection.

CONCLUSION

The distribution and putative expression of prolactin and its receptors in several neuronal tissues suggests that this hormone has pleiotropic functions in the brain.

Toxicogenomic analysis of pharmacological active coumarins isolated from Calophyllum brasiliense

Calophyllum brasiliense (Calophyllaceae) is a tropical rain forest tree, mainly distributed in South and Central America. It is an important source of bioactive natural products like, for instance soulatrolide, and mammea type coumarins. Soulatrolide is a tetracyclic dipyranocoumarins and a potent inhibitor of HIV-1 reverse transcriptase and Mycobacterium tuberculosis. Mammea A/BA and A/BB coumarins, pure or as a mixture, are highly active against several leukemia cell lines, Trypanosoma cruzi and Leishmania amazonensis. In the present work, a toxicogenomic analysis of Soulatrolide and Mammea A/BA + A/BB (3:1) mixture was performed in order to validate the toxicological potential of this type of compounds. Soulatrolide or mixture of mammea A/BA + A/BB (3:1) was administered orally to male mice (CD-1) at dose of 100 mg/kg/daily, for 1 week. After this time, mice were sacrificed, and RNA extracted from the liver of treated animals. Transcriptomic analysis was performed using Affymetrix Mouse Gene 1.0 ST Array. Robust microarray analysis (RMA) and two way ANOVA test revealed for mammea mixture treatment 46 genes upregulated and 72 downregulated genes; meanwhile, for soulatrolide 665 were upregulated and 1077 downregulated genes. Enrichment analysis for such genes revealed that in both type of treatments genetic expression were mainly involved in drug metabolism. Overall results indicate a safety profile. The microarray data complies with MIAME guidelines and are deposited in GEO under accession number GSE72755.