Hydrogen sulfide reduces oxidative stress in Huntington's disease via Nrf2.

JOURNAL/nrgr/04.03/01300535-202506000-00028/figure1/v/2024-08-05T133530Z/r/image-tiff The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular and cellular mechanisms by which quinolinic acid contributes to Huntington's disease pathology remain unknown. In this study, we established in vitro and in vivo models of Huntington's disease by administering quinolinic acid to the PC12 neuronal cell line and the striatum of mice, respectively. We observed a decrease in the levels of hydrogen sulfide in both PC12 cells and mouse serum, which was accompanied by down-regulation of cystathionine ß-synthase, an enzyme responsible for hydrogen sulfide production. However, treatment with NaHS (a hydrogen sulfide donor) increased hydrogen sulfide levels in the neurons and in mouse serum, as well as cystathionine ß-synthase expression in the neurons and the mouse striatum, while also improving oxidative imbalance and mitochondrial dysfunction in PC12 cells and the mouse striatum. These beneficial effects correlated with upregulation of nuclear factor erythroid 2-related factor 2 expression. Finally, treatment with the nuclear factor erythroid 2-related factor 2 inhibitor ML385 reversed the beneficial impact of exogenous hydrogen sulfide on quinolinic acid-induced oxidative stress. Taken together, our findings show that hydrogen sulfide reduces oxidative stress in Huntington's disease by activating nuclear factor erythroid 2-related factor 2, suggesting that hydrogen sulfide is a novel neuroprotective drug candidate for treating patients with Huntington's disease.

Luteolin alleviates muscle atrophy, mitochondrial dysfunction and abnormal FNDC5 expression in high fat diet-induced obese rats and palmitic acid-treated C2C12 myotubes.

Obesity is associated with a series of skeletal muscle impairments and dysfunctions, which are characterized by metabolic disturbances and muscle atrophy. Luteolin is a phenolic phytochemical with broad pharmacological activities. The present study aimed to evaluate the protective effects of Luteolin on muscle function and explore the potential mechanisms in high-fat diet (HFD)-induced obese rats and palmitic acid (PA)-treated C2C12 myotubes. Male Sprague-Dawley (SD) rats were fed with a control diet or HFD and orally administrated 0.5% sodium carboxymethyl cellulose (vehicle) or Luteolin (25, 50 and 100 mg/kg, respectively) for 12 weeks. The results showed that Luteolin ameliorated HFD-induced body weight gain, glucose intolerance and hyperlipidemia. Luteolin also alleviated muscle atrophy, decreased ectopic lipid deposition and prompted muscle-fiber-type conversion in the skeletal muscle. Meanwhile, we observed an evident improvement in mitochondrial quality control and respiratory capacity, accompanied by reduced oxidative stress. Mechanistic studies indicated that AMPK/SIRT1/PGC-1α signaling pathway plays a key role in the protective effects of Luteolin on skeletal muscle in the obese states, which was further verified by using specific inhibitors of AMPK and SIRT1. Moreover, the mRNA expression levels of markers in brown adipocyte formation were significantly up-regulated post Luteolin supplementation in different adipose depots. Taken together, these results revealed that Luteolin supplementation might be a promising strategy to prevent obesity-induced loss of mass and biological dysfunctions of skeletal muscle.

Polydopamine-Cloaked Nanoarchitectonics of Prussian Blue Nanoparticles Promote Functional Recovery in Neonatal and Adult Ischemic Stroke Models.

Ischemic stroke is a devastating disease and one of the leading causes of mortality worldwide. Overproduction of reactive oxygen species and inflammatory response contribute to secondary damage following ischemic insult. Nanozymes with robust anti-oxidative stress properties possess therapeutic possibility for ischemic insult. However, insufficiency of nanozyme accumulation in the neuronal mitochondria hindered their application. Herein, we constructed polydopamine-coated Prussian blue nanoparticles (PB@PDA NPs) to realize the targeting neuronal mitochondria for ischemic stroke, with the properties of antioxidant and anti-inflammation. After administration, much higher accumulation of PB@PDA NPs in the brain was observed compared to that in the PB NP group. Moreover, PB@PDA NPs effectively attenuated brain infarct than that of PB NPs in neonatal mice following hypoxia-ischemia (HI) insult. PB@PDA NPs mainly colocated with neuronal mitochondria in vivo and in vitro. Apart from attenuating oxidative stress, PB@PDA NPs also suppressed neuronal apoptosis and counteracted inflammation, which effectively promote a short- and long-term functional recovery in HI mice. Further, the therapeutic efficacy of PB@PDA NPs was also found in adult ischemic mice via tail vein injection. Collectively, these findings illustrate that PB@PDA NPs via system injection accumulate in neuronal mitochondria and are beneficial for ischemic stroke.

MiR-100-5p-rich small extracellular vesicles from activated neuron to aggravate microglial activation and neuronal activity after stroke.

Ischemic stroke is a common cause of mortality and severe disability in human and currently lacks effective treatment. Neuronal activation and neuroinflammation are the major two causes of neuronal damage. However, little is known about the connection of these two phenomena. This study uses middle cerebral artery occlusion mouse model and chemogenetic techniques to study the underlying mechanisms of neuronal excitotoxicity and severe neuroinflammation after ischemic stroke. Chemogenetic inhibition of neuronal activity in ipsilesional M1 alleviates infarct area and neuroinflammation, and improves motor recovery in ischemia mice. This study identifies that ischemic challenge triggers neuron to produce unique small extracellular vesicles (EVs) to aberrantly activate adjacent neurons which enlarge the neuron damage range. Importantly, these EVs also drive microglia activation to exacerbate neuroinflammation. Mechanistically, EVs from ischemia-evoked neuronal activity induce neuronal apoptosis and innate immune responses by transferring higher miR-100-5p to adjacent neuron and microglia. MiR-100-5p can bind to and activate TLR7 through U18U19G20-motif, thereby activating NF-κB pathway. Furthermore, knock-down of miR-100-5p expression improves poststroke outcomes in mice. Taken together, this study suggests that the combination of inhibiting aberrant neuronal activity and the secretion of specific EVs-miRNAs may serve as novel methods for stroke treatment.

α-Linolenic acid ameliorates pentylenetetrazol-induced neuron apoptosis and neurological impairment in mice with seizures via down-regulating JAK2/STAT3 pathway.

Epilepsy ranks fourth among neurological diseases, featuring spontaneous seizures and behavioural and cognitive impairments. Although anti-epileptic drugs are currently available clinically, 30 % of epilepsy patients are still ineffective in treatment and 52 % of patients experience serious adverse reactions. In this work, the neuroprotective effect of α-linolenic acid (ALA, a nutrient) in mice and its potential molecular mechanisms exposed to pentylenetetrazol (PTZ) was assessed. The mice were injected with pentetrazol 37 mg/kg, and ALA was intra-gastrically administered for 40 d. The treatment with ALA significantly reduced the overall frequency of epileptic seizures and improved the behaviour impairment and cognitive disorder caused by pentetrazol toxicity. In addition, ALA can not only reduce the apoptosis rate of brain neurons in epileptic mice but also significantly reduce the content of brain inflammatory factors (IL-6, IL-1 and TNF-α). Furthermore, we predicted that the possible targets of ALA in the treatment of epilepsy were JAK2 and STAT3 through molecular docking. Finally, through molecular docking and western blot studies, we revealed that the potential mechanism of ALA ameliorates PTZ-induced neuron apoptosis and neurological impairment in mice with seizures by down-regulating the JAK2/STAT3 pathway. This study aimed to investigate the anti-epileptic and neuroprotective effects of ALA, as well as explore its potential mechanisms, through the construction of a chronic ignition mouse model via intraperitoneal PTZ injection. The findings of this research provide crucial scientific support for subsequent clinical application studies in this field.

Diosmetin Ameliorates HFD-induced Cognitive Impairments via Inhibiting Metabolic Disorders, Mitochondrial Dysfunction and Neuroinflammation in Male SD Rats.

Currently, accumulating evidence has indicated that overnutrition-associated obesity may result in not only metabolic dysregulations, but also cognitive impairments. This study aimed to investigate the protective effects of Diosmetin, a bioflavonoid compound with multiple biological functions, on cognitive deficits induced by a high fat diet (HFD) and the potential mechanisms. In the present study, oral administration of Diosmetin (25, 50 and 100 mg/kg) for 12 weeks significantly reduced the body weight, restored glucose tolerance and normalized lipid profiles in the serum and liver in HFD-induced obese rats. Diosmetin also significantly ameliorated depression-like behaviors and impaired spatial memory in multiple behavioral tests, including the open field test, elevated plus-maze and Morris water maze, which was in accordance with the decreased pathological changes and neuronal damage in different regions of hippocampus as suggested by H&E and Nissl staining. Notably, our results also indicated that Diosmetin could significantly improve mitochondrial dysfunction induced by HFD through upregulating genes involved in mitochondrial biogenesis and dynamics, increasing mitochondrial ATP levels and inhibiting oxidative stress. Moreover, the levels of key enzymes involved in the TCA cycle were also significantly increased upon Diosmetin treatment. Meanwhile, Diosmetin inhibited HFD-induced microglial overactivation and down-regulated inflammatory cytokines both in the serum and hippocampus. In conclusion, these results indicated that Diosmetin might be a novel nutritional intervention to prevent the occurrence and development of obesity-associated cognitive dysfunction via metabolic regulation and anti-inflammation.

Luteolin ameliorates pentetrazole-induced seizures through the inhibition of the TLR4/NF-κB signaling pathway.

Epilepsy represents a prevalent neurological disorder in the population, and the existing antiepileptic drugs (AEDs) often fail to adequately control seizures. Inflammation is recognized as a pivotal factor in the pathophysiology of epilepsy. Luteolin, a natural flavonoid extract, possesses anti-inflammatory properties and exhibits promising neuroprotective activity. Nevertheless, the precise molecular mechanisms underlying the antiepileptic effects of luteolin remain elusive. In this study, we established a rat model of epilepsy using pentylenetetrazole (PTZ) to induce seizures. A series of behavioral experiments were conducted to assess behavioral abilities and cognitive function. Histological techniques, including HE staining, Nissl staining, and TUNEL staining, were employed to assess hippocampal neuronal damage. Additionally, Western blotting, RT-qPCR, and ELISA were utilized to analyze the expression levels of proteins involved in the TLR4/IκBα/NF-κB signaling pathway, transcription levels of apoptotic factors, and levels of inflammatory cytokines, respectively. Luteolin exhibited a dose-dependent reduction in seizure severity, prolonged the latency period of seizures, and shortened seizure duration. Furthermore, luteolin prevented hippocampal neuronal damage in PTZ-induced epileptic rats and partially restored behavioral function and learning and memory abilities. Lastly, PTZ kindling activated the TLR4/IκBα/NF-κB pathway, leading to elevated levels of the cytokines TNF-α, IL-6 and IL-1ß, which were attenuated by luteolin. Luteolin exerted anticonvulsant and neuroprotective activities in the PTZ-induced epileptic model. Its mechanism was associated with the inhibition of the TLR4/IκBα/NF-κB pathway, alleviating the immune-inflammatory response in the post-epileptic hippocampus.

Nicotinamide mononucleotide alleviates seizures via modulating SIRT1-PGC-1α mediated mitochondrial fusion and fission.

Both human and animal experiments have demonstrated that energy metabolism dysfunction in neurons after seizures is associated with an imbalance in mitochondrial fusion/fission dynamics. Effective neuronal mitochondrial dynamics regulation strategies remain elusive. Nicotinamide mononucleotide (NMN) can ameliorate mitochondrial functional and oxidative stress in age-related diseases. But whether NMN improves mitochondrial energy metabolism to exert anti-epileptic effects is unclear. This study aims to clarify if NMN can protect neurons from pentylenetetrazole (PTZ) or Mg2+ -free-induced mitochondrial disorder and apoptosis via animal and cell models. We established a continuous 30-day PTZ (37 mg/kg) intraperitoneal injection-induced epileptic mouse model and a cell model induced by Mg2+ -free solution incubation to explore the neuroprotective effects of NMN. We found that NMN treatment significantly reduced the seizure intensity of PTZ-induced epileptic mice, improved their learning and memory ability, and enhanced their motor activity and exploration desire. At the same time, in vitro and in vivo experiments showed that NMN can inhibit neuronal apoptosis and improve the mitochondrial energy metabolism function of neurons. In addition, NMN down-regulated the expression of mitochondrial fission proteins (Drp1 and Fis1) and promoted the expression of mitochondrial fusion proteins (Mfn1 and Mfn2) by activating the SIRT1-PGC-1α pathway, thereby inhibiting PTZ or Mg2+ -free extracellular solution-induced mitochondrial dysfunction, cell apoptosis, and oxidative stress. However, combined intervention of SIRT1 inhibitor, Selisistat, and PGC-1α inhibitor, SR-18292, eliminated the regulatory effect of NMN pre-treatment on mitochondrial fusion and fission proteins and apoptosis-related proteins. Therefore, NMN intervention may be a new potential treatment for cognitive impairment and behavioral disorders induced by epilepsy, and targeting the SIRT1-PGC-1α pathway may be a promising therapeutic strategy for seizures.

Nutritive/non-nutritive sweeteners and high fat diet contribute to dysregulation of sweet taste receptors and metabolic derangements in oral, intestinal and central nervous tissues.

OBJECTIVES: Overconsumption of non-nutritive sweeteners is associated with obesity, whereas the underlying mechanisms remain controversial. This study aimed to investigate the effects of long-term consumption of nutritive or non-nutritive sweeteners with or without high fat diet on sweet taste receptor expression in nutrient-sensing tissues and energy regulation dependent on sweet-sensing. METHODS: 50 Male Sprague-Dawley rats (140-160 g) were assigned to 10 groups (n = 5/group). All received fructose at 2.5% or 10%, sucralose at 0.01% or 0.015% or water with a normal chow diet or high fat diet for 12 weeks. Food and drink intake were monitored daily. Oral glucose tolerance test and intraperitoneal glucose tolerance test were performed at week 10 and 11 respectively. Serum was obtained for measurement of biochemical parameters. Tongue, duodenum, jejunum, ileum, colon and hypothalamus were rapidly removed to assess gene expression. RESULTS: Long-term consumption of sweeteners impaired glucose tolerance, increased calorie intake and body weight. A significant upregulation of sweet taste receptor expression was observed in all the four intestinal segments in groups fed 0.01% sucralose or 0.015% sucralose, most strikingly in the ileum, accompanied by elevated serum glucagon-like peptide-1 levels and up-regulated expression of sodium-dependent glucose cotransporter 1 and glucose transporter 2. A significant down-regulation in the tongue and hypothalamus was observed in groups fed 10% fructose or 0.015% sucralose, with alterations in hypothalamic appetite signals. The presence of high fat diet differentially modulates sweet taste perception in nutrient-sensing tissues. CONCLUSIONS: Long-term consumption of whether nutritive sweeteners or non-nutritive sweeteners combined with high fat diet contribute to dysregulation of sweet taste receptor expression in oral, intestinal and central nervous tissues.

Up-Regulation of miR-9-5p Inhibits Hypoxia-Ischemia Brain Damage Through the DDIT4-Mediated Autophagy Pathways in Neonatal Mice.

Introduction: Hypoxia-ischemia (HI) remains the leading cause of cerebral palsy and long-term neurological sequelae in infants. Despite intensive research and many therapeutic approaches, there are limited neuroprotective strategies against HI insults. Herein, we reported that HI insult significantly down-regulated microRNA-9-5p (miR-9-5p) level in the ipsilateral cortex of neonatal mice. Methods: The biological function and expression patterns of protein in the ischemic hemispheres were evaluated by qRT-PCR, Western Blotting analysis, Immunofluorescence and Immunohistochemistry. Open field test and Y-maze test were applied to detect locomotor activity and exploratory behavior and working memory. Results: Overexpression of miR-9-5p effectively alleviated brain injury and improved neurological behaviors following HI insult, accompanying with suppressed neuroinflammation and apoptosis. MiR-9-5p directly bound to the 3' untranslated region of DNA damage-inducible transcript 4 (DDIT4) and negatively regulated its expression. Furthermore, miR-9-5p mimics treatment down-regulated light chain 3 II/light chain 3 I (LC3 II/LC3 I) ratio and Beclin-1 expression and decreased LC3B accumulation in the ipsilateral cortex. Further analysis showed that DDIT4 knockdown conspicuously inhibited the HI-up-regulated LC3 II/ LC3 I ratio and Beclin-1 expression, associating with attenuated brain damage. Conclusion: The study indicates that miR-9-5p-mediated HI injury is regulated by DDIT4-mediated autophagy pathway and up-regulation of miR-9-5p level may provide a potential therapeutic effect on HI brain damage.

Mechanistic Insights into the Role of OPN in Mediating Brain Damage via Triggering Lysosomal Damage in Microglia/Macrophage.

We previously found that osteopontin (OPN) played a role in hypoxia-ischemia (HI) brain damage. However, its underlying mechanism is still unknown. Bioinformatics analysis revealed that the OPN protein was linked to the lysosomal cathepsin B (CTSB) and galectin-3 (GAL-3) proteins after HI exposure. In the present study, we tested the hypothesis that OPN was able to play a critical role in the lysosomal damage of microglia/macrophages following HI insult in neonatal mice. The results showed that OPN expression was enhanced, especially in microglia/macrophages, and colocalized with lysosomal-associated membrane protein 1 (LAMP1) and GAL-3; this was accompanied by increased LAMP1 and GAL-3 expression, CTSB leakage, as well as impairment of autophagic flux in the early stage of the HI process. In addition, the knockdown of OPN expression markedly restored lysosomal function with significant improvements in the autophagic flux after HI insult. Interestingly, cleavage of OPN was observed in the ipsilateral cortex following HI. The wild-type OPN and C-terminal OPN (Leu152-Asn294), rather than N-terminal OPN (Met1-Gly151), interacted with GAL-3 to induce lysosomal damage. Furthermore, the secreted OPN stimulated lysosomal damage by binding to CD44 in microglia in vitro. Collectively, this study demonstrated that upregulated OPN in microglia/macrophages and its cleavage product was able to interact with GAL-3, and secreted OPN combined with CD44, leading to lysosomal damage and exacerbating autophagosome accumulation after HI exposure.

Overexpression of CHAF1A is associated with poor prognosis, tumor immunosuppressive microenvironment and treatment resistance.

Background: As distinct marker of proliferating cells, chromatin assembly factor-1 (CAF-1) was critical in DNA replication. However, there is paucity information about the clinical significance, functions and co-expressed gene network of CHAF1A, the major subunit in CAF-1, in cancer. Methods: Bioinformatic analysis of CHAF1A and its co-expression gene network were performed using various public databases. Functional validation of CHAF1A was applied in breast cancer. Results: Overexpression of CHAF1A was found in 20 types of cancer tissues. Elevated expression of CHAF1A was positively correlated with breast cancer progression and poor patients' outcome. The analysis of co-expression gene network demonstrated CHAF1A was associated with not only cell proliferation, DNA repair, apoptosis, but cancer metabolism, immune system, and drug resistance. More importantly, higher expression of CHAF1A was positively correlated with immunosuppressive microenvironment and resistance to endocrine therapy and chemotherapy. Elevated expression of CHAF1A was confirmed in breast cancer tissues. Silencing of CHAF1A can significantly inhibit cell proliferation in MDA-MB-231 cells. Conclusion: The current work suggested that overexpression of CHAF1A can be used as diagnostic and poor prognostic biomarker of breast cancer. Higher expression of CHAF1A induced fast resistance to endocrine therapy and chemotherapy, it may be a promising therapeutic target and a biomarker to predict the sensitivity of immunotherapy in breast cancer.

Propionate ameliorates diabetes-induced neurological dysfunction through regulating the PI3K/Akt/eNOS signaling pathway.

A large body of research has established diabetes-related cognitive deterioration, sometimes known as "diabetic encephalopathy". Current evidence supports that oxidative stress, neuronal apoptosis, and cerebral microcirculation weakness are associated with cognition deficits induced by diabetes. The present study explores the effect of propionate on neurological deficits, cerebral blood flow, and oxidative stress in diabetic mice. Propionate in different doses (37.5, 75 and 150 mg/kg) was orally administrated daily. Here, we show that propionate can markedly improve neurological function, which is correlated with its capabilities of stimulating nitrogen monoxide (NO) production, increasing cerebral microcirculation, suppressing oxidative stress, and reducing neuron loss in the hippocampus. In addition, the results of Western Blotting indicated that the brain-protective function of propionate in streptozocin (STZ)-induced type 1 diabetes mellitus (T1DM) mice is related to phosphoinositide 3-kinase (PI3K)/serine-threonine protein kinase (Akt)/endothelial nitrogen monoxide synthase (eNOS) signaling pathway. In a diabetic mouse model, propionate reduces cerebral microcirculation, hippocampus apoptosis, and neurological impairment. Thus, propionate, now employed as a food preservative, may also help slow diabetes-induced cognitive loss.

Lycopene ameliorates insulin resistance and increases muscle capillary density in aging via activation of SIRT1.

Lycopene (Ly) is a kind of hydrocarbon, which belongs to the family of tetraterpene carotene and exists in red fruits and vegetables. The decrease of capillary density and blood flow with age is a significant reason for the increase of mortality and morbidity. Herein, our study aims to explore the effects of Ly (a bioactive food compound) on vascular aging in vitro and in vivo and its potential mechanisms. The cytological results showed that Ly could promote the proliferation of human umbilical vein endothelial cell (HUVECs) and enhance the ability of HUVECs to form capillary-like structures. Furthermore, the expression of SIRT1 in aged HUVECs was up-regulated. In vivo, aging rats showed signs of insulin resistance and blood vessel damage. Additionally, the capillary density and blood flow were reduced during the vascular aging process in both D-gal-induced and naturally aging muscle. However, when Ly was given, these conditions could be reversed. Simultaneously, the contents of ATP, lactic acid and pyruvic acid were determined, and it was found that Ly could promote angiogenesis by increasing the utilization rate of glucose and promoting energy metabolism. Finally, in the insulin resistance cell model, we knocked down the SIRT1 and administrated with Ly, and found that it couldn't restore insulin transdution. In conclusion, all the data in this study demonstrate that Ly could reactivate SIRT1 and improve insulin resistance, which was a reversible cause of vascular aging.

18ß-Glycyrrhetinic acid alleviates demyelination by modulating the microglial M1/M2 phenotype in a mouse model of cuprizone-induced demyelination.

This research aimed to examine the nutritious supplementary function of 18ß-Glycyrrhetinic acid (18ß-GA) in moderating the myelin sheath destruction and behavioral impairments observed in the cuprizone model of demyelination. Mice were fed daily on food containing cuprizone (0.3 %) and given doses of 18ß-GA (5 or 1 mg/kg) for a period of five weeks. The groups treated with 18ß-GA exhibited improvements in exploratory behavior, locomotive activity, and weight. As assessed using luxol-fast blue and myelin basic protein (MBP) staining, which were used to detect demyelination in the brain, 18ß-GA both reduced and prevented instances of cuprizone-induced demyelinating lesions; treatment with 18ß-GA also caused the MBP level in the corpus callosum to increase. Furthermore, alongside these positive results following 18ß-GA treatment, microglial polarisation was also observed to shift towards the beneficial M2 phenotype. The results of this research thus indicate the potential clinical application of 18ß-GA for the prevention of myelin damage and behavioral dysfunction.

Insulin injections inhibits PTZ-induced mitochondrial dysfunction, oxidative stress and neurological deficits via the SIRT1/PGC-1α/SIRT3 pathway.

With an associated 20% death risk, epilepsy mainly involves seizures of an unpredictable and recurrent nature. This study was designed to evaluate the neuroprotective effects and underlying mechanisms of insulin on mitochondrial disruption, oxidative stress, cell apoptosis and neurological deficits after epilepsy seizures. Mice were exposed to repetitive injections of pentylenetetrazol at a dose of 37 mg per kg. The influence of insulin was assessed by many biochemical assays, histopathological studies and neurobehavioral experiments. The administration of insulin was proven to increase the latency of seizures while also decreasing their intensity. It also caused a reversal of mitochondrial dysfunction and ameliorated oxidative stress. Additionally, insulin pretreatment upregulated Bcl-2, downregulated Bax, and then played a neuroprotective role against hippocampal neuron apoptosis. Furthermore, when insulin was administered, SIRT1/PGC-1α/SIRT3 signals were activated, possibly due to the fact that insulin's neuroprotective and anti-mitochondrial damage characteristics added to its observed antiepileptic functions. Finally, insulin treatment is thus extremely valuable for effecting improvements in neurological functions, as has been estimated in a series of functional tests. In conclude, the results of this study consequently demonstrate insulin to have significant potential for future application in epilepsy management.

Rational design and synthesis of 6-aryl-6H-benzo[c]chromenes as non-steroidal progesterone receptor antagonists for use against cancers.

Progesterone receptor (PR) antagonists have been found to be effective for treating certain human cancers. However, the steroidal structure of PR antagonists could bind to other hormone receptors, thus leading to serious side effects. On the other hand, non-steroidal PR antagonists have rarely been evaluated for their anti-cancer efficacy. Therefore, identifying novel non-steroidal PR antagonists possessing potent anti-cancer efficacy would be an attractive project to pursue. In this study, we presented a new metal-free oxidative CH arylation method to rapidly synthesize a series of 6-aryl-6H-benzo[c]chromene derivatives. Multiple cancer cell lines were used for their anti-cancer activity screening. An extensive analysis of structure-activity relationships (SAR) of the derivatives revealed that compounds 32 and 34 markedly inhibited the proliferation of MCF-7 cells with IC50 values of 6.32 ± 0.52 µM and 5.71 ± 0.49 µM, respectively. Further investigation indicated that derivatives 32 and 34 could elevate the expression of p21 and decrease the expressions of CDK4 and cyclin D1, leading to cell cycle arrest at G0/G1 phase. In addition, derivatives 32 and 34 could induce apoptosis of MCF-7 cells in both dose- and time-dependent manners by activation of p53 pathway, i.e., activation of Cleaved Caspase-3, p53 and P-p53 as well as elevation of the Bax/Bcl-2 ratio. Docking of derivatives 32 and 34 into a PR homology model exhibited potent PR antagonistic activity indicating the 6-aryl-6H-benzo[c]chromene derivatives are promising PR antagonists. We envisioned that derivatives 32 and 34 might be potential anti-cancer drug candidates as novel therapeutic treatment for breast cancer.

Butyrate alleviates PTZ-induced mitochondrial dysfunction, oxidative stress and neuron apoptosis in mice via Keap1/Nrf2/HO-1 pathway.

This study aims to evaluate the neuroprotective effect of sodium butyrate against the pentylenetetrazol (PTZ)-induced kindling epilepsy. Sodium butyrate (SB) (5, 10 and 20 mg/kg) and sodium valproate for 40 days and PTZ (37 mg/kg) injection every day were conducted for Kunming mice, to investigate seizure intensity and latency, oxidative stress parameters, mitochondrial structure and function, histopathology, and Keap1/Nrf2/HO-1 expressions. It is shown that seizure latency was effectively increased and the intensity of seizures decreased by treatment with sodium butyrate. It was also found to reverse the structural disruption of the mitochondria, reduce the ROS level and improve the levels of NAD + and ATP in the brains of epileptic mice. Furthermore, pretreatment with SB led to an increase in antioxidant enzyme activity (CAT, SOD and GSH-PX) in the brain as well as conferred a neuroprotective effect against neuron loss and apoptosis. The activation of Keap1/Nrf2/HO-1 signals was also identified, in which the antiepileptic effect of SB may be partially due to its anti-mitochondrial injury and neuroprotective activities. Accordingly, the results of a series of functional tests indicate a significant improvement of neurological function following SB treatment. In a mouse model of seizures, brain injury and neurological deficits can be attenuated by treatment with butyrate through the activation of Nrf2 pathway and the improvement of mitochondrial function.

Design, synthesis and biological evaluation of novel 1,3,4,9-tetrahydropyrano[3,4-b]indoles as potential treatment of triple negative breast cancer by suppressing PI3K/AKT/mTOR pathway.

Triple-negative breast cancer (TNBC) represents a subset of breast cancer characterized by high aggressiveness and poor prognosis. Currently, there is no curative therapeutic regimen for TNBC patients. In this study, molecular hybridization strategy is adopted by combining benzopyran and indole pharmacophores together, and a library of structurally simple 1,3,4,9-tetrahydropyrano[3,4-b]indoles was rapidly constructed. The structure-activity relationship studies indicated that compound 23 exhibited the most potent effect against the MDA-MB-231 cells with IC50 value of 2.29 µM. Mechanistic studies revealed that compound 23 inhibited cell proliferation via arresting cell cycle at G0/G1 phase. It induced cell apoptosis by disruption of mitochondrial membrane potential (MMP), accumulation of reactive oxygen species (ROS), reduction of glutathione (GSH), elevation of intracellular calcium ion (Ca2+) and activation of caspase cascade. Furthermore, compound 23 significantly inhibited the regulators of PI3K/AKT/mTOR pathway in MDA-MB-231 cells, suggesting that PI3K/AKT/mTOR pathway was involved in the 23-mediated apoptosis. To our knowledge, this is the first example of the anti-cancer activity study of indole-fused pyrans through suppressing PI3K/AKT/mTOR pathway. Overall, the current study suggested that compound 23 would serve as a promising lead compound for TNBC treatment.