Epilepsy is one of the most common brain disorder and, despite the possible use of several therapeutic options, many patients continue to have seizures for their entire lifespan and they need new ...therapeutic approaches. In the last years the interest on the non-psychoactive compounds present in Cannabis sativa has massively increased, and cannabidiol (CBD) has been shown to be effective in the treatment of different types of neurological disorders and neurodegenerative diseases such as epilepsy, ischemia, multiple sclerosis and Alzheimer's Disease.
We investigated the effects of the selected cannabinoids, Δ9-tetrahydrocannabinol (THC), CBD and cannabigerol (CBG) in rat organotypic hippocampal slices exposed to kainate, an in vitro seizure model. Cell death in the cornu Ammonis 3 (CA3) hippocampal subregion was quantified by propidium iodide fluorescence. Morphological analysis and tissue organization were examined by immunohistochemistry and confocal microscopy and microglia activation and polarization was evaluated using flow cytometry and morphology analysis.
When present in the incubation medium, cannabidiol reduced dose-dependent CA3 injury induced by kainate. Conversely, incubation with THC exacerbated hippocampal damage. The neuroprotective effects of cannabidiol were blocked by TRPV1, TRPV2, 5-HT1A, and PPARγ antagonists. Confocal microscopy confirmed that CBD but not THC had a significant protective effect against neuronal damage and tissue disorganization caused by kainate. Cannabidiol incubation significantly block the microglia activation from the M0 to M1 phenotype observed in the kainate in-vitro seizure model, pushing toward a transition from M0 to M2.
Our results suggest that CBD mitigated neuronal damage induced by kainate and blocked the transition from the M0 to the M1 phenotype.
•CBD but not THC is neuroprotective in an in-vitro seizure model.•TRPV2 and 5-HT1A receptors mediate the neuroprotective effects of CBD.•CBD but not THC reverts kainate induced microglia phagocytosis of damage neurons.•CBD blocks the transition from an M0 to M1 microglia phenotype induced by kainate.
Phenomics, the complexity of microglia phenotypes and their related functions compels the continuous study of microglia in disease animal models to find druggable targets for neurodegenerative ...disorders. Activation of microglia was long considered detrimental for neuron survival, but more recently it has become apparent that the real scenario of microglia morphofunctional diversity is far more complex. In this review, we discuss the recent literature on the alterations in microglia phenomics in the hippocampus of animal models of normal brain aging, acute neuroinflammation, ischemia, and neurodegenerative disorders, such as AD. Microglia undergo phenomic changes consisting of transcriptional, functional, and morphological changes that transform them into cells with different properties and functions. The classical subdivision of microglia into M1 and M2, two different, all-or-nothing states is too simplistic, and does not correspond to the variety of phenotypes recently discovered in the brain. We will discuss the phenomic modifications of microglia focusing not only on the differences in microglia reactivity in the diverse models of neurodegenerative disorders, but also among different areas of the brain. For instance, in contiguous and highly interconnected regions of the rat hippocampus, microglia show a differential, finely regulated, and region-specific reactivity, demonstrating that microglia responses are not uniform, but vary significantly from area to area in response to insults. It is of great interest to verify whether the differences in microglia reactivity may explain the differential susceptibility of different brain areas to insults, and particularly the higher sensitivity of CA1 pyramidal neurons to inflammatory stimuli. Understanding the spatiotemporal heterogeneity of microglia phenomics in health and disease is of paramount importance to find new druggable targets for the development of novel microglia-targeted therapies in different CNS disorders. This will allow interventions in three different ways: (i) by suppressing the pro-inflammatory properties of microglia to limit the deleterious effect of their activation; (ii) by modulating microglia phenotypic change to favor anti-inflammatory properties; (iii) by influencing microglia priming early in the disease process.
Cannabinoids, used for centuries for recreational and medical purposes, have potential therapeutic value in stroke treatment. Cannabidiol (CBD), a non-psychoactive compound and partial agonist of ...TRPV2 channels, is efficacious in many neurological disorders. We investigated the effects of CBD or Δ9-tetrahydrocannabinol (THC) in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation (OGD), an in vitro model of ischemia. Neuronal TRPV2 expression decreased after OGD, but it increased in activated, phagocytic microglia. CBD increased TRPV2 expression, decreased microglia phagocytosis, and increased rod microglia after OGD. THC had effects contrary to those of CBD. Our results show that cannabinoids have different effects in ischemia. CBD showed neuroprotective effects, mediated, at least in part, by TRPV2 channels, since the TRPV2 antagonist tranilast blocked them, while THC worsened the neurodegeneration caused by ischemia. In conclusion, our results suggest that different cannabinoid molecules play different roles in the mechanisms of post-ischemic neuronal death. These different effects of cannabinoid observed in our experiments caution against the indiscriminate use of cannabis or cannabinoid preparations for recreational or therapeutic use. It was observed that the positive effects of CBD may be counteracted by the negative effects caused by high levels of THC.
The complexity of microglia phenotypes and their related functions compels the continuous study of microglia in diseases animal models. We demonstrated that oxygen-glucose deprivation (OGD) induced ...rapid, time- and space-dependent phenotypic microglia modifications in CA1 stratum pyramidalis (SP) and stratum radiatum (SR) of rat organotypic hippocampal slices as well as the degeneration of pyramidal neurons, especially in the outer layer of SP. Twenty-four h following OGD, many rod microglia formed trains of elongated cells spanning from the SR throughout the CA1, reaching the SP outer layer where they acquired a round-shaped amoeboid phagocytic head and phagocytosed most of the pyknotic, damaged neurons. NIR-laser treatment, known to preserve neuronal viability after OGD, prevented rod microglia formation. In CA3 SP, pyramidal neurons were less damaged, no rod microglia were found. Thirty-six h after OGD, neuronal damage was more pronounced in SP outer and inner layers of CA1, rod microglia cells were no longer detectable, and most microglia were amoeboid/phagocytic. Damaged neurons, more numerous 36 h after OGD, were phagocytosed by amoeboid microglia in both inner and outer layers of CA1. In response to OGD, microglia can acquire different morphofunctional phenotypes which depend on the time after the insult and on the subregion where microglia are located.
Interest has been focused in recent years on the analgesic effects exerted by adenosine and its receptors, A
1
, A
2A
, A
2B
, and A
3
adenosine receptor (AR) subtypes, in different in vivo models ...of chronic pain. In particular, it was demonstrated that selective A
3
AR agonists reduced pro-nociceptive N-type Ca
2+
channels in dorsal root ganglion (DRG) neurons isolated from rats and, by this mechanism, inhibit post inflammatory visceral hypersensitivity. In the present study, we investigate the effect of a previously reported irreversibly binding A
3
AR agonist, ICBM, on Ca
2+
currents (I
Ca
) in rat DRG neurons. Present data demonstrate that ICBM, an isothiocyanate derivative designed for covalent binding to the receptor, concentration-dependently inhibits I
Ca
. This effect is irreversible, since it persists after drug removal, differently from the prototypical A
3
AR agonist, Cl-IB-MECA. ICBM pre-exposure inhibits the effect of a subsequent Cl-IB-MECA application. Thus, covalent A
3
AR agonists such as ICBM may represent an innovative, beneficial, and longer-lasting strategy to achieve efficacious chronic pain control versus commonly used, reversible, A
3
AR agonists. However, the possible limitations of this drug and other covalent drugs may be, for example, a characteristic adverse effect profile, suggesting that more pre-clinical studies are needed.
Passiflora edulis Sims is a liana species of high economic interest and is an interesting model plant for understanding ozone action on disturbed vegetation. In this work we hypothesized that P. ...edulis has adaptive responses to oxidative stress that enable it to tolerate ozone damage based on its capacity to grow under a diversity of environmental conditions and to dominate disturbed areas. We exposed seedlings to three levels of ozone in a Free-Air Controlled Exposure (FACE) system (22, 41 and 58 ppb h AOT40 and 13.52, 17.24 and 20.62 mmol m−2 POD0, over 97 days) for identifying its tolerance mechanisms. Anatomical (leaf blade structure and fluorescence emission of chloroplast metabolites), physiological (leaf gas exchange, growth rate and biomass production) and biochemical (pigments, total sugars, starch, enzymatic and non-enzymatic antioxidant metabolites, reactive oxygen species and lipid peroxidation derivatives) responses were assessed. Ozone caused decreased total number of leaves, hyperplasia and hypertrophy of the mesophyll cells, and accelerated leaf senescence. However, O3 did not affect carbohydrates content, net photosynthetic rate, or total biomass production, indicating that the carboxylation efficiency and associated physiological processes were not affected. In addition, P. edulis showed higher leaf contents of ascorbic acid, glutathione (as well high ratio between their reduced and total forms), carotenoids, and flavonoids located in the chloroplast outer envelope membrane. Our results indicate that P. edulis is an O3-tolerant species due to morphological acclimation responses and an effective antioxidant defense system represented by non-enzymatic antioxidants, which maintained the cellular redox balance under ozone.
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•Seedlings of Passiflora edulis were exposed to ozone in a FACE system.•Anatomical changes observed in leaf tissue may restrain damage progression.•A high level of O3 did not affect physiological processes.•Biochemical leaf traits enable P. edulis to tolerate oxidative stress.•P. edulis can be considered an O3-tolerant species.
Background: Fractional ablative and non-ablative lasers are useful treatments for skin rejuvenation. A procedure that provides the sequential application of fractional ablative followed by ...non-ablative laser treatment may reduce patients’ downtime and deliver better cosmetic results than with either laser alone. Objective: The purpose of the current study was to demonstrate the ameliorative and therapeutic effects in skin remodeling of the synergistic use of the two laser wavelengths (fractional ablative CO2 and non-ablative 1540 nm) with three different types of pulse shapes, S-Pulse (SP), D-Pulse (DP) and H-Pulse (HP), through which the CO2 laser can emit, performing an ex vivo histological evaluation. Methods: In this prospective study, ex vivo sheep inner thigh skin was chosen due to its similarity to human skin tissue, and a histological evaluation was performed. Three irradiation conditions, using all of the three CO2 pulse shapes (alone or averaged), were investigated: (1) 10.600 nm alone, the sequential irradiation of the two wavelengths in the same perfectly controlled energy pulses (DOT) for the entire scan area; ((2) 10.600 nm followed immediately by 1540 nm; and (3) 1540 nm followed immediately by 10.600 nm). Results: When comparing ablative to sequential irradiations, the synergy of the two wavelengths did not alter the typical ablative pulse shape of the 10.600 nm laser alone. With the same CO2 pulse shape, the lesion depth did not vary with the synergy of the two wavelengths, while thermal lesion width increased compared to CO2 alone. The ablation rate was achieved, while the total thermal lesion coverage in the scanning area of CO2 − 1540 lasers was greater than when using CO2 alone and then the other sequential irradiation. Conclusions: This study provides important preclinical data for new and early uses of the novel 10.600/1540 nm dual-wavelength non-ablative fractional laser. The synergy of the two wavelengths enhanced all the benefits already available when using CO2 laser systems both in terms of tone strengthening, thanks to a greater shrinking effect, and in terms of stimulation and collagen remodeling thanks to a greater volumetric thermal effect.
Cerebral ischemia is a multifactorial pathology characterized first by an acute injury, due to excitotoxicity, followed by a secondary brain injury that develops hours to days after ischemia. During ...ischemia, adenosine acts as an endogenous neuroprotectant. Few studies have investigated the role of A
2B
receptor in brain ischemia because of the low potency of adenosine for it and the few selective ligands developed so far. A
2B
receptors are scarcely but widely distributed in the brain on neurons, glial and endothelial cells and on hematopoietic cells, lymphocytes and neutrophils, where they exert mainly anti-inflammatory effects, inhibiting vascular adhesion and inflammatory cells migration. Aim of this work was to verify whether chronic administration of the A
2B
agonist, BAY60-6583 (0.1 mg/kg i.p., twice/day), starting 4 h after focal ischemia induced by transient (1 h) Middle Cerebral Artery occlusion (tMCAo) in the rat, was protective after the ischemic insult. BAY60-6583 improved the neurological deficit up to 7 days after tMCAo. Seven days after ischemia BAY60-6583 reduced significantly the ischemic brain damage in cortex and striatum, counteracted ischemia-induced neuronal death, reduced microglia activation and astrocytes alteration. Moreover, it decreased the expression of TNF-α and increased that of IL-10 in peripheral plasma. Two days after ischemia BAY60-6583 reduced blood cell infiltration in the ischemic cortex. The present study indicates that A
2B
receptors stimulation can attenuate the neuroinflammation that develops after ischemia, suggesting that A
2B
receptors may represent a new interesting pharmacological target to protect from degeneration after brain ischemia.
Light-based therapies have been proven to influence and perhaps reverse skin ageing at clinical, molecular and histologic levels. Laser technology decreases photodamage by promoting collagen type I ...and III synthesis and enhancing the expression of heat shock protein. Aims: This study aims to assess different doses of 675 nm irradiation on human dermal fibroblast cells to evaluate the potential therapeutic effects on the rejuvenation process. Methods: This study employed a laser system that emits 675 nm wavelength: 260, 390, 520 and 650 J/cm2 doses were tested on adult human dermal fibroblast cells. Cellular viability, proliferation, and synthesis of type I and III collagen were studied. Results: No dose tested showed effects on cell viability and proliferation at 24 and 48 h from the irradiation. Doses of 260 and 520 J/cm2 causes a significant decrease in type I collagen fluorescence intensity, while 390 J/cm2 elicits a significant increase in type III collagen expression. Conclusions: Our results showed that 675 nm laser irradiation does not affect cell viability while modulating cell proliferation and collagen synthesis in human adult cultured fibroblasts in vitro. These findings suggest that 675 nm laser irradiation potentially plays a role in skin rejuvenation.
•Change in type I/III collagen ratio induces premature ageing.•675 nm irradiation can modulate cultured human dermal fibroblasts.•675 nm irradiation directly affects collagen synthesis stimulating neocollagenesis.•Potential role of 675 nm in skin rejuvenation via modulating collagen synthesis.•Light-based therapy can reduce photodamage.
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