The Neuroactive Steroid Pregnanolone Glutamate: Anticonvulsant Effect, Metabolites and Its Effect on Neurosteroid Levels in Developing Rat Brains

Pregnanolone glutamate (PA-G) is a neuroactive steroid that has been previously demonstrated to be a potent neuroprotective compound in several biological models in vivo. Our in vitro experiments identified PA-G as an inhibitor of N-methyl-D-aspartate receptors and a potentiator of γ-aminobutyric acid receptors (GABAARs). In this study, we addressed the hypothesis that combined GABAAR potentiation and NMDAR antagonism could afford a potent anticonvulsant effect. Our results demonstrated the strong age-related anticonvulsive effect of PA-G in a model of pentylenetetrazol-induced seizures. PA-G significantly decreased seizure severity in 12-day-old animals, but only after the highest dose in 25-day-old animals. Interestingly, the anticonvulsant effect of PA-G differed both qualitatively and quantitatively from that of zuranolone, an investigational neurosteroid acting as a potent positive allosteric modulator of GABAARs. Next, we identified 17-hydroxy-pregnanolone (17-OH-PA) as a major metabolite of PA-G in 12-day-old animals. Finally, the administration of PA-G demonstrated direct modulation of unexpected neurosteroid levels, namely pregnenolone and dehydroepiandrosterone sulfate. These results suggest that compound PA-G might be a pro-drug of 17-OH-PA, a neurosteroid with a promising neuroprotective effect with an unknown mechanism of action that may represent an attractive target for studying perinatal neural diseases.

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Diosgenin Prevents Microglial Activation and Protects Dopaminergic Neurons from Lipopolysaccharide-Induced Neural Damage In Vitro and In Vivo

International Journal of Molecular Sciences ◽

10.3390/ijms221910361 ◽

2021 ◽

Vol 22 (19) ◽

pp. 10361

Author(s):

Shou-Lun Lee ◽

Ssu-Chieh Tu ◽

Ming-Yen Hsu ◽

Ting-Yu Chin

Keyword(s):

Dopaminergic Neurons ◽

Dopaminergic Neuron ◽

Microglial Activation ◽

Neuroprotective Effect ◽

Motor Dysfunction ◽

Primary Microglia ◽

Neural Damage ◽

Age Related

Background: The prevention of age-related neurodegenerative disorders is an important issue in an aging society. Microglia-mediated neuroinflammation resulting in dopaminergic neuron loss may lead to the pathogenesis of Parkinson’s disease (PD). Lipopolysaccharide (LPS), an endotoxin, induces neuroinflammatory microglial activation, contributing to dopaminergic neuron damage. Diosgenin is a phytosteroid sapogenin with a wide spectrum of pharmacological activities, e.g., anti-inflammatory activity. However, the preventive effect of diosgenin on neuroinflammation is not clear. Thus, in this study, we further investigated the neuroprotective effect of diosgenin on LPS-induced neural damage in vitro and in vivo. Methods: For in vitro experiments, primary mesencephalic neuron-glia cultures and primary microglia cultures isolated from Sprague–Dawley rats were used. Cells were pretreated with diosgenin and then stimulated with LPS. The expression of proinflammatory cytokines or tyrosine hydroxylase (TH) in the cells was analyzed. In vivo, rats were fed a diet containing 0.1% (w/w) diosgenin for 4 weeks before being administered a unilateral substantia nigra (SN) injection of LPS. Four weeks after the LPS injection, the rats were assessed for lesion severity using the amphetamine-induced rotation test and TH immunohistochemistry. Results: Diosgenin pretreatment prevented LPS-induced neurite shortening in TH-positive neurons in mesencephalic neuron-glia cultures. In addition, pretreatment of primary microglia with diosgenin significantly reduced tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) expression. Moreover, diosgenin pretreatment significantly suppressed LPS-induced extracellular signal-regulated kinase (ERK) activation. In vivo, the intranigral injection of LPS in rats fed a diosgenin-containing diet significantly improved motor dysfunction and reduced TH expression in SN. Conclusion: These results support the effectiveness of diosgenin in protecting dopaminergic neurons from LPS-induced neuroinflammation.

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In vivo Evaluation and Alzheimer’s Disease Treatment Outcome of siRNA Loaded Dual Targeting Drug Delivery System

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666190204141046 ◽

2019 ◽

Vol 20 (1) ◽

pp. 56-62 ◽

Cited By ~ 1

Author(s):

Chi Zhang ◽

Zhichun Gu ◽

Long Shen ◽

Xianyan Liu ◽

Houwen Lin

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Treatment Outcome ◽

Neuroprotective Effect ◽

Sirna Delivery ◽

Repeated Administration ◽

Spatial Learning And Memory ◽

In Vivo Evaluation

Background: To deliver drugs to treat Alzheimer’s Disease (AD), nanoparticles should firstly penetrate through blood brain barrier, and then target neurons. Methods: Recently, we developed an Apo A-I and NL4 dual modified nanoparticle (ANNP) to deliver beta-amyloid converting enzyme 1 (BACE1) siRNA. Although promising in vitro results were obtained, the in vivo performance was not clear. Therefore, in this study, we further evaluated the in vivo neuroprotective effect and toxicity of the ANNP/siRNA. The ANNP/siRNA was 80.6 nm with good stability when incubated with serum. In vivo, the treatment with ANNP/siRNA significantly improves the spatial learning and memory of APP/PS1 double transgenic mice, as determined by mean escape latency, times of crossing the platform area during the 60 s swimming and the percentage of the distance in the target quadrant. Results and Conclusion: After the treatment, BACE1 RNA level of ANNP/siRNA group was greatly reduced, which contributed a good AD treatment outcome. Finally, after repeated administration, the ANNP/siRNA did not lead to significant change as observed by HE staining of main organs, suggesting the good biocompatibility of ANNP/siRNA. These results demonstrated that the ANNP was a good candidate for AD targeting siRNA delivery.

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Regorafenib-Attenuated, Bleomycin-Induced Pulmonary Fibrosis by Inhibiting the TGF-β1 Signaling Pathway

International Journal of Molecular Sciences ◽

10.3390/ijms22041985 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1985

Author(s):

Xiaohe Li ◽

Ling Ma ◽

Kai Huang ◽

Yuli Wei ◽

Shida Long ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Signaling Pathway ◽

Transforming Growth Factor ◽

Kinase Inhibitor ◽

In Vivo Experiments ◽

Age Related ◽

And Migration ◽

Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a fatal and age-related pulmonary disease. Nintedanib is a receptor tyrosine kinase inhibitor, and one of the only two listed drugs against IPF. Regorafenib is a novel, orally active, multi-kinase inhibitor that has similar targets to nintedanib and is applied to treat colorectal cancer and gastrointestinal stromal tumors in patients. In this study, we first identified that regorafenib could alleviate bleomycin-induced pulmonary fibrosis in mice. The in vivo experiments indicated that regorafenib suppresses collagen accumulation and myofibroblast activation. Further in vitro mechanism studies showed that regorafenib inhibits the activation and migration of myofibroblasts and extracellular matrix production, mainly through suppressing the transforming growth factor (TGF)-β1/Smad and non-Smad signaling pathways. In vitro studies have also indicated that regorafenib could augment autophagy in myofibroblasts by suppressing TGF-β1/mTOR (mechanistic target of rapamycin) signaling, and could promote apoptosis in myofibroblasts. In conclusion, regorafenib attenuates bleomycin-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway.

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Impact of Polyphenolic-Food on Longevity: An Elixir of Life. An Overview

Antioxidants ◽

10.3390/antiox10040507 ◽

2021 ◽

Vol 10 (4) ◽

pp. 507

Author(s):

Rosaria Meccariello ◽

Stefania D’Angelo

Keyword(s):

Oxidative Stress ◽

Food Sources ◽

Preventive Action ◽

Nutritional Interventions ◽

Beneficial Effects ◽

Age Related ◽

Macromolecular Damage ◽

And Oxidative Stress

Aging and, particularly, the onset of age-related diseases are associated with tissue dysfunction and macromolecular damage, some of which can be attributed to accumulation of oxidative damage. Recently, growing interest has emerged on the beneficial effects of plant-based diets for the prevention of chronic diseases including obesity, diabetes, and cardiovascular disease. Several studies collectively suggests that the intake of polyphenols and their major food sources may exert beneficial effects on improving insulin resistance and related diabetes risk factors, such as inflammation and oxidative stress. They are the most abundant antioxidants in the diet, and their intake has been associated with a reduced aging in humans. Polyphenolic intake has been shown to be effective at ameliorating several age-related phenotypes, including oxidative stress, inflammation, impaired proteostasis, and cellular senescence, both in vitro and in vivo. In this paper, effects of these phytochemicals (either pure forms or polyphenolic-food) are reviewed and summarized according to affected cellular signaling pathways. Finally, the effectiveness of the anti-aging preventive action of nutritional interventions based on diets rich in polyphenolic food, such as the diets of the Blue zones, are discussed.

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Complement C5 is not critical for the formation of sub-RPE deposits in Efemp1 mutant mice

Scientific Reports ◽

10.1038/s41598-021-89978-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Donita L. Garland ◽

Eric A. Pierce ◽

Rosario Fernandez-Godino

Keyword(s):

Macular Degeneration ◽

Retinal Pigment ◽

Age Related Macular Degeneration ◽

Deposit Formation ◽

Genetic Ablation ◽

Age Related ◽

Complement Dysregulation

AbstractThe complement system plays a role in the formation of sub-retinal pigment epithelial (RPE) deposits in early stages of age-related macular degeneration (AMD). But the specific mechanisms that connect complement activation and deposit formation in AMD patients are unknown, which limits the development of efficient therapies to reduce or stop disease progression. We have previously demonstrated that C3 blockage prevents the formation of sub-RPE deposits in a mouse model of EFEMP1-associated macular degeneration. In this study, we have used double mutant Efemp1R345W/R345W:C5-/- mice to investigate the role of C5 in the formation of sub-RPE deposits in vivo and in vitro. The data revealed that the genetic ablation of C5 does not eliminate the formation of sub-RPE deposits. Contrarily, the absence of C5 in RPE cultures promotes complement dysregulation that results in increased activation of C3, which likely contributes to deposit formation even in the absence of EFEMP1-R345W mutant protein. The results also suggest that genetic ablation of C5 alters the extracellular matrix turnover through an effect on matrix metalloproteinases in RPE cell cultures. These results confirm that C3 rather than C5 could be an effective therapeutic target to treat early AMD.

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Phytochemical Study and In Vitro Screening Focusing on the Anti-Aging Features of Various Plants of the Greek Flora

Antioxidants ◽

10.3390/antiox10081206 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1206

Author(s):

Aimilia D. Sklirou ◽

Maria T. Angelopoulou ◽

Aikaterini Argyropoulou ◽

Eliza Chaita ◽

Vasiliki Ioanna Boka ◽

...

Keyword(s):

Plant Species ◽

High Performance ◽

High Resolution Mass Spectrometry ◽

Ultra Performance Liquid Chromatography ◽

Skin Aging ◽

Rosa Damascena ◽

Phytochemical Study ◽

Age Related

Skin health is heavily affected by ultraviolet irradiation from the sun. In addition, senile skin is characterized by major changes in the collagen, elastin and in the hyaluronan content. Natural products (NPs) have been shown to delay cellular senescence or in vivo aging by regulating age-related signaling pathways. Moreover, NPs are a preferable source of photoprotective agents and have been proven to be useful against the undesirable skin hyperpigmentation. Greek flora harvests great plant diversity with approximately 6000 plant species, as it has a wealth of NPs. Here, we report an extensive screening among hundreds of plant species. More than 440 plant species and subspecies were selected and evaluated. The extracts were screened for their antioxidant and anti-melanogenic properties, while the most promising were further subjected to various in vitro and cell-based assays related to skin aging. In parallel, their chemical profile was analyzed with High-Performance Thin-Layer Chromatography (HPTLC) and/or Ultra-Performance Liquid Chromatography High-Resolution Mass Spectrometry (UPLC-HRMS). A variety of extracts were identified that can be of great value for the cosmetic industry, since they combine antioxidant, photoprotective, anti-melanogenic and anti-aging properties. In particular, the methanolic extracts of Sideritis scardica and Rosa damascena could be worthy of further attention, since they showed interesting chemical profiles and promising properties against specific targets involved in skin aging.

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Neuroprotective Effects of the FGF21 Analogue LY2405319

Journal of Alzheimer s Disease ◽

10.3233/jad-200837 ◽

2021 ◽

pp. 1-13

Author(s):

Claire Rühlmann ◽

David Dannehl ◽

Marcus Brodtrück ◽

Andrew C. Adams ◽

Jan Stenzel ◽

...

Keyword(s):

Glial Cells ◽

Neuroprotective Effect ◽

Amyloid Β ◽

Fibroblast Growth Factor 21 ◽

Neuroprotective Effects ◽

Organotypic Brain Slice ◽

Brain Slice Cultures ◽

Abca1 Mrna

Background: To date, there are no effective treatments for Alzheimer’s disease (AD). Thus, a significant need for research of therapies remains. Objective: One promising pharmacological target is the hormone fibroblast growth factor 21 (FGF21), which is thought to be neuroprotective. A clinical candidate for medical use could be the FGF21 analogue LY2405319 (LY), which has a specificity and potency comparable to FGF21. Methods: The present study investigated the potential neuroprotective effect of LY via PPARγ/apoE/abca1 pathway which is known to degrade amyloid-β (Aβ) plaques by using primary glial cells and hippocampal organotypic brain slice cultures (OBSCs) from 30- and 50-week-old transgenic APPswe/PS1dE9 (tg) mice. By LY treatment of 52-week-old tg mice with advanced Aβ deposition, we further aimed to elaborate the effect of LY on AD pathology in vivo. Results: LY application to primary glial cells caused an upregulation of pparγ, apoE, and abca1 mRNA expression and significantly decreased number and area of Aβ plaques in OBSCs. LY treatment in tg mice increased cerebral [18F] FDG uptake and N-acetylaspartate/creatine ratio indicating enhanced neuronal activity and integrity. Although LY did not reduce the number of Aβ plaques in tg mice, the number of iba1-positive cells was significantly decreased indicating reduced microgliosis. Conclusion: These data identified LY in vitro as an activator of Aβ degrading genes leading to cerebral Aβ load amelioration in early and late AD pathology. Although Aβ plaque reduction by LY failed in vivo, LY may be used as therapeutic agent to treat AD-related neuroinflammation and impaired neuronal integrity.

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Neuroprotective Effect of Optimized Yinxieling Formula in 6-OHDA-Induced Chronic Model of Parkinson’s Disease through the Inflammation Pathway

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2019/2529641 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Renrong Wei ◽

Cuiping Rong ◽

Qingfeng Xie ◽

Shouhai Wu ◽

Yuchao Feng ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Calcium Binding ◽

Dopaminergic Neurons ◽

Neuroprotective Effect ◽

Interleukin 1 ◽

Mrna Levels ◽

Cox 2

Parkinson’s disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra (SN)-striatum circuit, which is associated with glial activation and consequent chronic neuroinflammation. Optimized Yinxieling Formula (OYF) is a Chinese medicine that exerts therapeutical effect and antiinflammation property on psoriasis. Our previous study has proven that pretreatment with OYF could regulate glia-mediated inflammation in an acute mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Given that PD is a chronic degeneration disorder, this study applied another PD animal model induced by striatal injection of 6-hydroxydopamine (6-OHDA) to mimic the progressive damage of the SN-striatum dopamine system in rats. The OYF was administrated in the manner of pretreatment plus treatment. The effects of the OYF on motor behaviors were assessed with the apomorphine-induced rotation test and adjusting steps test. To confirm the effect of OYF on dopaminergic neurons and glia activation in this model, we analyzed the expression of tyrosine hydroxylase (TH) and glia markers, ionized calcium-binding adapter molecule 1 (Iba-1), and glial fibrillary acidic protein (GFAP) in the SN region of the rat PD model. Inflammation-associated factors, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were further evaluated in this model and in interferon-γ- (INF-γ-) induced murine macrophages RAW264.7 cells. The results from the in vivo study showed that OYF reversed the motor behavioral dysfunction in 6-OHDA-induced PD rats, upregulated the TH expression, decreased the immunoreactivity of Iba-1 and GFAP, and downregulated the mRNA levels of TNF-α and COX-2. The OYF also trended to decrease the mRNA levels of IL-1β and iNOS in vivo. The results from the in vitro study showed that OYF significantly decreased the mRNA levels of TNF-α, IL-1β, IL-6, iNOS, and COX-2. Therefore, this study suggests that OYF exerts antiinflammatory effects, which might be related to the protection of dopaminergic neurons in 6-OHDA-induced chronic neurotoxicity.

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The anti-angiogenic isoforms of VEGF in health and disease

Biochemical Society Transactions ◽

10.1042/bst0371207 ◽

2009 ◽

Vol 37 (6) ◽

pp. 1207-1213 ◽

Cited By ~ 76

Author(s):

Yan Qiu ◽

Coralie Hoareau-Aveilla ◽

Sebastian Oltean ◽

Steven J. Harper ◽

David O. Bates

Keyword(s):

Splice Site ◽

Site Selection ◽

Age Related Macular Degeneration ◽

Splicing Factor ◽

Splice Site Selection ◽

Age Related ◽

Normal Human ◽

Radical Revision

Anti-angiogenic VEGF (vascular endothelial growth factor) isoforms, generated from differential splicing of exon 8, are widely expressed in normal human tissues but down-regulated in cancers and other pathologies associated with abnormal angiogenesis (cancer, diabetic retinopathy, retinal vein occlusion, the Denys–Drash syndrome and pre-eclampsia). Administration of recombinant VEGF165b inhibits ocular angiogenesis in mouse models of retinopathy and age-related macular degeneration, and colorectal carcinoma and metastatic melanoma. Splicing factors and their regulatory molecules alter splice site selection, such that cells can switch from the anti-angiogenic VEGFxxxb isoforms to the pro-angiogenic VEGFxxx isoforms, including SRp55 (serine/arginine protein 55), ASF/SF2 (alternative splicing factor/splicing factor 2) and SRPK (serine arginine domain protein kinase), and inhibitors of these molecules can inhibit angiogenesis in the eye, and splice site selection in cancer cells, opening up the possibility of using splicing factor inhibitors as novel anti-angiogenic therapeutics. Endogenous anti-angiogenic VEGFxxxb isoforms are cytoprotective for endothelial, epithelial and neuronal cells in vitro and in vivo, suggesting both an improved safety profile and an explanation for unpredicted anti-VEGF side effects. In summary, C-terminal distal splicing is a key component of VEGF biology, overlooked by the vast majority of publications in the field, and these findings require a radical revision of our understanding of VEGF biology in normal human physiology.

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