Narciclasine inhibits LPS-induced neuroinflammation by modulating the Akt/IKK/NF-κB and JNK signaling pathways

Effects of arsenic exposure on the PI3K/Akt/NF-κB signaling pathway in the hippocampus of offspring mice at different developmental stages

The primary purpose of present study was to explore the effects of arsenic exposure on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/nuclear transcription factor-κB (NF-κB) signaling pathway in the hippocampus of offspring mice at different developmental stages. Sodium arsenite (NaAsO2) at doses of 0, 15, 30 or 60 mg/L administered to female mice and their pups. The nuclear translocation levels of NF-κB were assessed by EMSA. Real-time RT-PCR was used to measure Akt, NF-κB and PI3K mRNA levels. Protein expressions of PI3K, p-Akt, inhibitor kappa B kinase (IKK), p-NF-κB, protein kinase A (PKA), inhibitor kappa B (IκB), and cAMP response element-binding protein (CREB) were measured by Western blot. Results disclosed that exposure to 60 mg/L NaAsO2 could suppress NF-κB levels of nuclear translocation of postnatal day (PND) 20 and PND 40 mice. Arsenic downregulated the transcriptional and translational levels of PI3K, Akt and NF-κB. Additionally, protein expressions of p-IKK, p-IκB, PKA and p-CREB also reduced. Taken together, results of present study indicated that arsenic could downregulate the PI3K/Akt/NF-κB signaling pathway, particularly on PND 40, which might be involved in the cognitive impairments.

Anti-inflammatory Principles of the Plant Family Amaryllidaceae

There is considerable interest in the utilisation of plants against inflammation. Over 50 species of the plant family Amaryllidaceae are known for such usage in traditional medicine. This review was undertaken to identify the chemical principles responsible for these anti-inflammatory effects. It describes the findings from in vitro, in vivo and in silico studies, as well as the probes made on the mechanisms of action. The literature search returned over 600 hits, of which around 130 were chosen for their relevance to the text. Over 140 compounds have thus far been screened for anti-inflammatory effects. These were mostly isoquinoline alkaloids but also included other classes of secondary metabolites such as chromones, flavonoids and triterpenoids. In vitro studies were carried out in mononuclear cells such as lymphocytes, monocytes, neutrophils and macrophages, against which no serious side effects were observed. The constituents were also effective against inflammation induced by physical and chemical stimuli in a variety of murine test subjects. Chief among the compounds were the isoquinoline alkaloids lycorine and narciclasine, which displayed potent effects against pain, swelling, asthma and arthritis, amongst others. From a mechanistic perspective, several of the compounds were shown to mediate in inflammatory pathways, notably via the modulation of both pro-inflammatory (such as NF-κB, TNF-α and IL-1) and anti-inflammatory (such as IL-10 and TGF-β) factors. Useful insights also emerged from active-site docking studies of some of the compounds. The Amaryllidaceae affords a rich and diverse platform for the discovery of potential anti-inflammatory drugs.

A pharmacological toolkit for human microglia identifies Topoisomerase I inhibitors as immunomodulators for Alzheimer's disease

While efforts to identify microglial subtypes have recently accelerated, the relation of transcriptomically defined states to function has been largely limited to in silico annotations. Here, we characterize a set of pharmacological compounds that have been proposed to polarize human microglia towards two distinct states - one enriched for AD and MS genes and another characterized by increased expression of antigen presentation genes. Using different model systems including HMC3 cells, iPSC-derived microglia and cerebral organoids, we characterize the effect of these compounds in mimicking human microglial subtypes in vitro. We show that the Topoisomerase I inhibitor Camptothecin induces a CD74high/MHChigh microglial subtype which is specialized in amyloid beta phagocytosis. Camptothecin suppressed amyloid toxicity and restored microglia back to their homeostatic state in a zebrafish amyloid model. Our work provides avenues to recapitulate human microglial subtypes in vitro, enabling functional characterization and providing a foundation for modulating human microglia in vivo.

Clerodane diterpenoids with in-vitro anti-neuroinflammatory activity from the tuberous root of Tinospora sagittata (Menispermaceae)

Twenty-six clerodane diterpenoids have been isolated from T. sagittata, a plant species of traditional Chinese medicine Radix Tinosporae, also named as "Jin Guo Lan". Among them, there are eight previously undescribed clerodane diterpenoids (tinotanoids A-H: 1-8), and 18 known diterpenoids (9-26). The absolute configurations of compounds 1, 2, 5, 8, 13, 17 and 20 were determined by single-crystal X-ray diffraction. Compound 1 is the first example of rotameric clerodane diterpenoid with a γ-lactone ring which is constructed between C-11 and C-17; meanwhile, compounds 3 and 4 are two pairs of inseparable epimers. Compounds 2, 12 and 17 demonstrated excellent inhibitory activity on NO production against LPS-stimulated BV-2 cells with IC50 values of 9.56 ± 0.69, 9.11 ± 0.53 and 11.12 ± 0.70 μM, respectively. These activities were significantly higher than that of the positive control minocycline (IC50 = 23.57 ± 0.92 μM). Moreover, compounds 2, 12 and 17 dramatically reduced the LPS-induced upregulation of iNOS and COX-2 expression. Compounds 2 and 12 significantly inhibited the levels of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 that were increased by LPS stimulation.

Ilexchinene, a new seco-ursane triterpenoid from the leaves of Ilex chinensis with therapeutic effect on neuroinflammation by attenuating the MAPK/NF-κB signaling pathway

BACKGROUND

Neuroinflammation is a vital factor participating in the whole pathogenetic process of diverse neurodegenerative disorders, but accessible clinical drugs are still insufficient due to their inefficacy and side effects. Triterpenoids are reported to possess potential anti-neuroinflammatory activities, and the leaves of Ilex chinensis are a commonly used herbal medicine containing many ursane-type and oleanane-type triterpenoids. However, the novel triterpenoids from I. chinensis and their underlying mechanisms are still elusive.

PURPOSE

To isolate novel seco-ursane triterpenoids with anti-neuroinflammatory effects from the leaves of I. chinensis and reveal their underlying mechanisms.

STUDY DESIGN AND METHODS

The novel compound was purified by column chromatography and identified by comprehensive spectroscopic experiments. The LPS-induced BV-2 cell model and LPS-induced acute murine brain inflammation model were used to assess the anti-neuroinflammatory effect of the structure and further understand its underlying mechanisms by cell viability, ELISA, Western blot analysis, qRT‒PCR analysis, behavior analysis, H&E staining, and immunofluorescence staining experiments.

RESULTS

Ilexchinene is a novel ursane-type triterpenoid with a rare 18,19-seco-ring skeleton that was first isolated and identified from I. chinensis. Ilexchinene evidently reduced the overexpression of inflammatory substances in vitro. A mechanistic study suggested that ilexchinene could decrease NF-κB activation to prevent the formation of the NLRP3 inflammasome in the early neuroinflammatory response; in addition, it could prevent the phosphorylation of ERK and JNK. In vivo, ilexchinene remarkably improved LPS-induced mouse behavioral deficits and diminished the number of overactivated microglial cells. Furthermore, ilexchinene evidently diminished the overexpression of inflammatory substances in mouse brains. A mechanistic study confirmed that ilexchinene markedly suppressed the MAPK/NF-κB pathway to relieve the neuroinflammatory response.

CONCLUSION

We identified a novel 18,19-seco-ursane triterpenoid from the leaves of I. chinensis and revealed its underlying mechanism of neuroinflammation for the first time. These findings suggest that ilexchinene might possess promising therapeutic effects in neuroinflammation.

Agarperoxinols A and B: Two Unprecedented Tricyclic 6/6/7 Rearranged Humulene-Type Sesquiterpenoids That Attenuated the Neuroinflammation in LPS-Stimulated Microglial Models

Agarperoxinols A and B (1-2), two naturally occurring humulene-type sesquiterpenoids with an unprecedented tricyclic 6/6/7 ring, were discovered from the agarwood of Aquilaria malaccensis. Their structures were unambiguously determined by various spectroscopic data, experimental ECD calculations, and single-crystal X-ray diffraction analysis. Agarperoxinol B showed significant and dose-dependent neuroinflammatory inhibitory effects on various proinflammatory mediators, including NO, TNF-α, IL-6, and IL-1β, and suppressed iNOS and COX-2 enzymes in LPS-activated microglial cells. A mechanistic study demonstrated that agarperoxinol B remarkably inhibited the phosphorylation of the Akt and JNK signaling pathways. Agarperoxinol B also significantly reduced the expression of the microglial markers Iba-1, COX-2, and TNF-α in the mouse cerebral cortex. Our findings introduce a bioactive compound from natural products that decreases proinflammatory factor production and has application for the treatment of neurodegenerative diseases.

Controlled Decompression Alleviates Motor Dysfunction by Regulating Microglial Polarization via the HIF-1α Signaling Pathway in Intracranial Hypertension

Decompressive craniectomy (DC) is a major form of surgery that is used to reduce intracranial hypertension (IH), the most frequent cause of death and disability following severe traumatic brain injury (sTBI) and stroke. Our previous research showed that controlled decompression (CDC) was more effective than rapid decompression (RDC) with regard to reducing the incidence of complications and improving outcomes after sTBI; however, the specific mechanisms involved have yet to be elucidated. In the present study, we investigated the effects of CDC in regulating inflammation after IH and attempted to identify the mechanisms involved. Analysis showed that CDC was more effective than RDC in alleviating motor dysfunction and neuronal death in a rat model of traumatic intracranial hypertension (TIH) created by epidural balloon pressurization. Moreover, RDC induced M1 microglia polarization and the release of pro-inflammatory cytokines. However, CDC treatment resulted in microglia primarily polarizing into the M2 phenotype and induced the significant release of anti-inflammatory cytokines. Mechanistically, the establishment of the TIH model led to the increased expression of hypoxia-inducible factor-1α (HIF-1α); CDC ameliorated cerebral hypoxia and reduced the expression of HIF-1α. In addition, 2-methoxyestradiol (2-ME2), a specific inhibitor of HIF-1α, significantly attenuated RDC-induced inflammation and improved motor function by promoting M1 to M2 phenotype transformation in microglial and enhancing the release of anti-inflammatory cytokines. However, dimethyloxaloylglycine (DMOG), an agonist of HIF-1α, abrogated the protective effects of CDC treatment by suppressing M2 microglia polarization and the release of anti-inflammatory cytokines. Collectively, our results indicated that CDC effectively alleviated IH-induced inflammation, neuronal death, and motor dysfunction by regulating HIF-1α-mediated microglial phenotype polarization. Our findings provide a better understanding of the mechanisms that underlie the protective effects of CDC and promote clinical translational research for HIF-1α in IH.

Cocktail of three isoquinoline alkaloids derived from Glaucium grandiflorum Boiss. & A. Huet subsp. refractum (Nábelek) Mory inhibits the production of LPS-induced ROS, pro-inflammatory cytokines, and mediators through the down-regulation of p38 MAPK in BV-2 cells

Glaucium grandiflorum extracts have traditionally been used to treat brain-related disorders. G. grandiflorum extracts also exhibited inhibitory effects on cholinesterase enzymes, as well as antigenotoxic activity. However, no research has been done on the effect of G. grandiflorum alkaloid extracts on the anti-oxidative and anti-inflammatory mechanisms. In this study we aimed to evaluate the anti-oxidative and anti-inflammatory activities of the alkaloid extract obtained from G. grandiflorum as well as the mechanisms responsible for their neuroprotective effects in neuronal damage caused by LPS in BV2 cells. We used LC-MS/MS and 1H, 13C NMR analysis to determine the presence of major alkaloids (allocryptopine, tetrahydropalmatine, and tetrahydroberberine N-oxide (trans-cannadine-N-oxide) in the alkaloid extracts. We used flow cytometry to study the alkaloid extracts' effects on ROS production; we also employed qRT-PCR and Western Blot to analyze the effects of oxidative stress and inflammation-related genes and proteins. ROS production within the cell was inhibited by chloroform alkaloid extract (CAE). There occurred marked CAE-induced reductions in IL-1β, Cox-2, and iNOS mRNA expressions. We also observed marked reductions in IL-6 and TNF-α mRNA expressions with methanol alkaloid extract (MAE). CAE effectively suppressed IL-1β and iNOS protein levels, especially as in qRT-PCR studies, while MAE effectively reduced IL-6 and TNF-α protein levels. Additionally, MAE was found to be prominent in suppressing the levels of Cox-2 protein, unlike qRT-PCR studies. According to our study findings, oxidative stress brought about by inflammation was suppressed by alkaloid extracts from G. grandiflorum which can be attributed to their suppressor effects on the pro-inflammatory cytokines-mediators, and p38 MAPK. As a result, a drug active substance that suppresses oxidative stress and inflammation has been brought to the neuropharmacological field.

The RhoA-ROCK1/ROCK2 Pathway Exacerbates Inflammatory Signaling in Immortalized and Primary Microglia

Neuroinflammation is a unifying factor among all acute central nervous system (CNS) injuries and chronic neurodegenerative disorders. Here, we used immortalized microglial (IMG) cells and primary microglia (PMg) to understand the roles of the GTPase Ras homolog gene family member A (RhoA) and its downstream targets Rho-associated coiled-coil-containing protein kinases 1 and 2 (ROCK1 and ROCK2) in neuroinflammation. We used a pan-kinase inhibitor (Y27632) and a ROCK1- and ROCK2-specific inhibitor (RKI1447) to mitigate a lipopolysaccharide (LPS) challenge. In both the IMG cells and PMg, each drug significantly inhibited pro-inflammatory protein production detected in media (TNF-α, IL-6, KC/GRO, and IL-12p70). In the IMG cells, this resulted from the inhibition of NF-κB nuclear translocation and the blocking of neuroinflammatory gene transcription (iNOS, TNF-α, and IL-6). Additionally, we demonstrated the ability of both compounds to block the dephosphorylation and activation of cofilin. In the IMG cells, RhoA activation with Nogo-P4 or narciclasine (Narc) exacerbated the inflammatory response to the LPS challenge. We utilized a siRNA approach to differentiate ROCK1 and ROCK2 activity during the LPS challenges and showed that the blockade of both proteins may mediate the anti-inflammatory effects of Y27632 and RKI1447. Using previously published data, we show that genes in the RhoA/ROCK signaling cascade are highly upregulated in the neurodegenerative microglia (MGnD) from APP/PS-1 transgenic Alzheimer's disease (AD) mice. In addition to illuminating the specific roles of RhoA/ROCK signaling in neuroinflammation, we demonstrate the utility of using IMG cells as a model for primary microglia in cellular studies.

Developmental toxicity and inflammatory response induced by Botrytis cinerea in zebrafish (Danio rerio) larvae

Botrytis cinerea can reduce the yield of fruits and vegetables by infecting plants. The conidia produced by Botrytis cinerea can be transmitted to the aquatic environment via air and water, but the effects of Botrytis cinerea on aquatic animals is unknown. In this research, the influence of Botrytis cinerea on the development, inflammation, and apoptosis of zebrafish larvae and the underlying mechanism was evaluated. Results indicated that, compared with the control group, the larvae exposed to 10¹-10³ CFU/mL of Botrytis cinerea spore suspension had a delayed hatching rate, lower head and eye area, shorter body length, and larger yolk sac at 72 h post-fertilization. In addition, the quantitative fluorescence intensity of treated larvae displayed a dose-dependent increase in apoptosis sign, revealing that Botrytis cinerea could generate apoptosis. Subsequently, zebrafish larvae were inflamed after exposure to Botrytis cinerea spore suspension, which was characterized as inflammatory infiltration and macrophage aggregation in the intestine. The enrichment of the pro-inflammatory factor TNF-α activated the NF-κB signaling pathway, generating the increase of the transcription level of target genes (jak3, pi3k, pdk1, akt, and ikk2) and the high expression of major proteins NF-κB (P65) in this pathway. Likewise, elevated content of TNF-α could activate JNK, which turned on the P53 apoptotic pathway, leading to a significant increase in the bax, caspase3, and caspase9 transcript abundances. This study demonstrated that Botrytis cinerea could cause developmental toxicity, morphological malformation, inflammation, and cell apoptosis in zebrafish larvae, which provided data support and a theoretical basis for ecological health risk assessment and filled the gap in biological research of Botrytis cinerea.

Nanotopographic micro-nano forces finely tune the conformation of macrophage mechanosensitive membrane protein integrin β2 to manipulate inflammatory responses

Finely tuning mechanosensitive membrane proteins holds great potential in precisely controlling inflammatory responses. In addition to macroscopic force, mechanosensitive membrane proteins are reported to be sensitive to micro-nano forces. Integrin β2, for example, might undergo a piconewton scale stretching force in the activation state. High-aspect-ratio nanotopographic structures were found to generate nN-scale biomechanical force. Together with the advantages of uniform and precisely tunable structural parameters, it is fascinating to develop low-aspect-ratio nanotopographic structures to generate micro-nano forces for finely modulating their conformations and the subsequent mechanoimmiune responses. In this study, low-aspect-ratio nanotopographic structures were developed to finely manipulate the conformation of integrin β2. The direct interaction of forces and the model molecule integrin αXβ2 was first performed. It was demonstrated that pressing force could successfully induce conformational compression and deactivation of integrin αXβ2, and approximately 270 to 720 pN may be required to inhibit its conformational extension and activation. Three low-aspect-ratio nanotopographic surfaces (nanohemispheres, nanorods, and nanoholes) with various structural parameters were specially designed to generate the micro-nano forces. It was found that the nanorods and nanohemispheres surfaces induce greater contact pressure at the contact interface between macrophages and nanotopographic structures, particularly after cell adhesion. These higher contact pressures successfully inhibited the conformational extension and activation of integrin β2, suppressing focal adhesion activity and the downstream PI3K-Akt signaling pathway, reducing NF-κB signaling and macrophage inflammatory responses. Our findings suggest that nanotopographic structures can be used to finely tune mechanosensitive membrane protein conformation changes, providing an effective strategy for precisely modulating inflammatory responses.

Electronic Supplementary Material

Supplementary material (primer sequences of target genes in RT-qPCR assay; the results of solvent accessible surface area during equilibrium simulation, the ligplut results of hydrogen bonds, and hydrophobic interactions; the density of different nanotopographic structures; interaction analysis of the downregulated leading genes of "focal adhesion" signaling pathway in nanohemispheres and nanorods groups; and the GSEA results of "Rap 1 signaling pathway" and "regulation of actin cytoskeleton" in different groups) is available in the online version of this article at 10.1007/s12274-023-5550-0.

Neuroprotective Effect of Methanolic Ajwa Seed Extract on Lipopolysaccharide-Induced Memory Dysfunction and Neuroinflammation: In Vivo, Molecular Docking and Dynamics Studies

Islamic literature has indicated that daily consumption of Ajwa dates heals a variety of chronic diseases and disorders. The current research investigates the neuroprotective effect of methanolic Ajwa seed extract (MASE) on lipopolysaccharide (LPS)-induced cognitive deficits using multiple approaches. For animal studies, MASE (200 and 400 mg/kg, p.o.) was administrated for thirty consecutive days, and four doses of LPS (250 µg/kg, i.p.) were injected to induce neurotoxicity. Memory functions were evaluated using elevated plus-maze and novel object recognition tests. Acetylcholine (ACh) and neuroinflammatory markers (cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and transforming growth factor (TGF)-β1) were estimated in brain tissues. Studies of molecular docking and dynamics were conducted to provide insight into the molecular-level mechanisms. MASE administration resulted in a significant reversal of LPS-induced memory impairment in both maze models. Both doses of MASE elevated the ACh levels in an LPS-treated rat brain. In addition, the extract lowered COX-2 and proinflammatory cytokines (TNF-α and IL-6) while increasing anti-inflammatory cytokines (IL-10 and TGF-β1) in LPS-treated brain tissues. Molecular modeling results revealed that the compound's ellagic acid, epicatechin, catechin, kaempferol, quercetin, and apigenin have the potential to act as a dual inhibitor of acetylcholinesterase (AChE) and COX-2 and can be responsible for the improvement of both cholinergic and inflammatory conditions, while the cinnamic acid, hesperidin, hesperetin, narengin, and rutin compounds are responsible only for the improvement of cholinergic transmission. The above compounds acted by interacting with the key residues Trp84, Asp72, Gly118, Ser200, Tyr334, and His440, which are responsible for the hydrolysis of ACh in AChE, while the COX-2 is inhibited by interacting with the residues (Val349, Leu352, Tyr355, Tyr385, Ala527, Ser530, and Leu531) of the hydrophobic channel. By promoting cholinergic activity and protecting neuroinflammation in the rat brain, MASE provides neuroprotection against LPS-induced cognitive deficits. Our preliminary findings will help with further drug discovery processes related to neuroinflammation-related neurodegeneration.

Turmeronols (A and B) from Curcuma longa have anti-inflammatory effects in lipopolysaccharide-stimulated BV-2 microglial cells by reducing NF-κB signaling

Turmeronols (A and B), bisabolane-type sesquiterpenoids found in turmeric, reduce inflammation outside the brain in animals; however, their effects on neuroinflammation, a common pathology of various neurodegenerative diseases, are not understood. Inflammatory mediators produced by microglial cells play a key role in neuroinflammation, so this study evaluated the anti-inflammatory effects of turmeronols in BV-2 microglial cells stimulated with lipopolysaccharide (LPS). Pretreatment with turmeronol A or B significantly inhibited LPS-induced nitric oxide (NO) production; mRNA expression of inducible NO synthase; production of interleukin (IL)-1β, IL-6, and tumor necrosis factor α and upregulation of their mRNA expression; phosphorylation of nuclear factor-κB (NF-κB) p65 proteins and inhibitor of NF-κB kinase (IKK); and nuclear translocation of NF-κB. These results suggest that these turmeronols may prevent the production of inflammatory mediators by inhibiting the IKK/NF-κB signaling pathway in activated microglial cells and can potentially treat neuroinflammation associated with microglial activation.

3',4'-Dihydroxyflavonol Attenuates Lipopolysaccharide-Induced Neuroinflammatory Responses of Microglial Cells by Suppressing AKT-mTOR and NF-κB Pathways

Microglia-related neuroinflammation contributes to the pathogenesis of a variety of neurodegenerative disorders such as Alzheimer's disease. The synthetic flavonoid, 3',4'-dihydroxyflavonol (3,3',4'-trihydroxyflavone), has been shown to protect brain or myocardial ischemia reperfusion-induced cell death and prevent the aggregation of amyloid-β protein, a process that causes progressive neurodegeneration in Alzheimer's disease. Here, we explored the anti-neuroinflammatory ability of 3',4'-dihydroxyflavonol in lipopolysaccharide (LPS)-activated MG6 microglial cells. 3',4'-Dihydroxyflavonol attenuated LPS-induced tumor necrosis factor-α and nitric oxide secretion in MG6 cells. LPS-induced phosphorylation of mammalian target of rapamycin (mTOR), nuclear factor-κB (NF-κB), and protein kinase B (AKT) (which are all associated with the neuroinflammatory response in microglia) were attenuated by 3',4'-dihydroxyflavonol treatment. Treatment with the mTOR inhibitor, rapamycin, NF-κB inhibitor, caffeic acid phenethyl ester, or AKT inhibitor, LY294002, also attenuated LPS-induced tumor necrosis factor-α and nitric oxide secretion in MG6 cells. LY294002 treatment attenuated LPS-induced phosphorylation of mTOR and NF-κB in MG6 cells. Hence, our study suggests that 3',4'-dihydroxyflavonol can attenuate the neuroinflammatory response of microglial cells by suppressing the AKT-mTOR and NF-κB pathways.

Narciclasine ameliorated T cell mediated acute liver injury through activating AMPK pathway

Hepatitis is closely related to cirrhosis and liver cancer, and it is vital that we develop new drugs and identify new drug targets. Traditional Chinese medicine has demonstrated excellent curative effects on liver diseases. The ingredients from Chinese herbals are important source for drug development in the treatment of hepatitis. Here, we found that narciclasine (NCS), a major component extracted from narcissus bulbs, showed hepatoprotective effect against concanavalin A (Con A) induced hepatitis. NCS treatment significantly reduced hepatocyte death, hepatic inflammatory cells infiltration, and serum cytokine levels in Con A challenged mice. We further observed that NCS directly inhibited Con A induced splenocytes proliferation and cytokine production in vitro. RNA-seq results showed that genes related to immune response were upregulated in Con A treated CD4⁺ T cells, which were down-regulated in the presence of NCS. Moreover, the AMPK pathway had been found activated in response to NCS treatment, suggesting a potential target for NCS targets. In conclusion, our results reveal that NCS is a powerful immunosuppressor against T cell activation, thus leading to protection against Con A induced liver injury in mice. These findings provide new insights into the use of natural products in the treatment of autoimmune hepatitis.

Neuroprotective Mechanism of Icariin on Hypoxic Ischemic Brain Damage in Neonatal Mice

Objective

Our previous results showed that icariin (ICA) could inhibit apoptosis and provide neuroprotection against hypoxic-ischemic brain damage (HIBD) in neonatal mice, but the specific mechanism of its neuroprotective effect remains unknown. This study aims at exploring whether ICA plays a neuroprotective role in apoptosis inhibition by regulating autophagy through the estrogen receptor α (ERα)/estrogen receptor β (ERβ) pathway in neonatal mice with HIBD.

Methods

A neonatal mouse model of HIBD was constructed in vivo, and an oxygen and glucose deprivation (OGD) model in HT22 cells from the hippocampal neuronal system was constructed in vitro. The effects of ICA pretreatment on autophagy and the expression of ERα and ERβ were detected in vitro and in vivo, respectively. ICA pretreatment was also supplemented with the autophagy inhibitor 3-methyladenine (3-MA), ERα inhibitor methylpiperidino pyrazole (MPP), and ERβ inhibitor 4-(2-phenyl-5,7-bis (trifluoromethyl) pyrazolo [1,5-a] pyramidin-3-yl) phenol (PHTPP) to further detect whether ICA pretreatment can activate the ERα/ERβ pathway to promote autophagy and reduce HIBD-induced apoptosis to play a neuroprotective role against HIBD in neonatal mice.

Results

ICA pretreatment significantly promoted autophagy in HIBD mice. Treatment with 3-MA significantly inhibited the increase in autophagy induced by ICA pretreatment, reversed the neuroprotective effect of ICA pretreatment, and promoted apoptosis. Moreover, ICA pretreatment significantly increased the expression levels of the ERα and ERβ proteins in HIBD newborn mice. Both MPP and PHTPP administration significantly inhibited the expression levels of the ERα and ERβ proteins activated by ICA pretreatment, reversed the neuroprotective effects of ICA pretreatment, inhibited the increase in autophagy induced by ICA pretreatment, and promoted apoptosis.

Conclusion

ICA pretreatment may promote autophagy by activating the ERα and ERβ pathways, thus reducing the apoptosis induced by HIBD and exerting a neuroprotective effect on neonatal mice with HIBD.

Kaempferol and atherosclerosis: From mechanism to medicine

Natural products possess pleiotropic cardiovascular protective effects owing to their anti-oxidation, anti-inflammation and anti-thrombotic properties. Kaempferol, (3,5,7-trihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one), is a kind of naturally occurring flavonoid existing in many common fruits and vegetables (e.g., onions, broccoli, strawberries and grapes) and particularly in traditional Chinese medicine as exemplified by Ginkgo biloba. Epidemiological, preclinical and clinical studies have revealed an inverse association between the consumption of kaempferol-containing foods and medicines and the risk of developing cardiovascular diseases. Numerous translational studies in experimental animal models and cultured cells have demonstrated a wide range of pharmacological activities of kaempferol. In this article, we reviewed the antioxidant, anti-inflammatory and cardio-protective activities of kaempferol and elucidated the potential molecular basis of the therapeutic capacity of kaempferol by focusing on its anti-atherosclerotic effects. Overall, the review presents the health benefits of kaempferol-containing plants and medicines and reflects on the potential of kaempferol as a possible drug candidate to prevent and treat atherosclerosis, the underlying pathology of most cardiovascular diseases.

Amaryllidaceae Alkaloids Decrease the Proliferation, Invasion, and Secretion of Clinically Relevant Cytokines by Cultured Human Colon Cancer Cells

Alkaloids isolated from members of the Amaryllidaceae plant family are promising anticancer agents. The purpose of the current study was to determine if the isocarbostyrils narciclasine, pancratistatin, lycorane, lycorine, crinane, and haemanthamine inhibit phenomena related to cancer progression in vitro. To achieve this, we examined the proliferation, adhesion, and invasion of cultured human colon cancer cells via MTT assay and Matrigel-coated Boyden chambers. In addition, Luminex assays were used to quantify the secretion of matrix metalloproteinases (MMP) and cytokines associated with poor clinical outcomes. We found that all alkaloids decreased cell proliferation regardless of TP53 status, with narciclasine exhibiting the greatest potency. The effects on cell proliferation also appear to be specific to cancer cells. Narciclasine, lycorine, and haemanthamine decrease both adhesion and invasion but with various potencies depending on the cell line. In addition, narciclasine, lycorine, and haemanthamine decreased the secretion of MMP-1, -2, and -7, as well as the secretion of the cytokines pentraxin 3 and vascular endothelial growth factor. In conclusion, the present study shows that Amaryllidaceae alkaloids decrease phenomena and cytokines associated with colorectal cancer progression, supporting future investigations regarding their potential as multifaceted drug candidates.

Analyzing the Systems Biology Effects of COVID-19 mRNA Vaccines to Assess Their Safety and Putative Side Effects

COVID-19 vaccines have been instrumental tools in reducing the impact of SARS-CoV-2 infections around the world by preventing 80% to 90% of hospitalizations and deaths from reinfection, in addition to preventing 40% to 65% of symptomatic illnesses. However, the simultaneous large-scale vaccination of the global population will indubitably unveil heterogeneity in immune responses as well as in the propensity to developing post-vaccine adverse events, especially in vulnerable individuals. Herein, we applied a systems biology workflow, integrating vaccine transcriptional signatures with chemogenomics, to study the pharmacological effects of mRNA vaccines. First, we derived transcriptional signatures and predicted their biological effects using pathway enrichment and network approaches. Second, we queried the Connectivity Map (CMap) to prioritize adverse events hypotheses. Finally, we accepted higher-confidence hypotheses that have been predicted by independent approaches. Our results reveal that the mRNA-based BNT162b2 vaccine affects immune response pathways related to interferon and cytokine signaling, which should lead to vaccine success, but may also result in some adverse events. Our results emphasize the effects of BNT162b2 on calcium homeostasis, which could be contributing to some frequently encountered adverse events related to mRNA vaccines. Notably, cardiac side effects were signaled in the CMap query results. In summary, our approach has identified mechanisms underlying both the expected protective effects of vaccination as well as possible post-vaccine adverse effects. Our study illustrates the power of systems biology approaches in improving our understanding of the comprehensive biological response to vaccination against COVID-19.

The novel anti-neuroinflammatory functional food CCL01, a mixture of Cuscuta seed extracts and Lactobacillus paracasei NK112

Neuroinflammation, which occurs due to microglia, is related to the pathogenesis of neurodegenerative disorders. Recently, the development of functional foods that down-regulate over-activated microglial cells to prevent the progression of neurodegenerative disorders has been proposed, since over-activated microglia induce a chronic source of neurotoxic factors and reduce neuronal survival. Thus, the anti-neuroinflammatory effects of a functional food mixture (CCL01) including Cuscuta seeds and Lactobacillus paracasei NK112 on lipopolysaccharide (LPS)-induced experimental models were investigated. In LPS-induced in vitro models, the expression levels of inflammatory mediators (e.g., inducible nitric oxide synthase, cyclooxygenase-2, nitric oxide, and prostaglandin E2) and pro-inflammatory cytokines (e.g., tumor necrosis factor-α, interleukin (IL)-1β, and IL-6) were decreased upon CCL01 treatment. CCL01 showed an anti-neuroinflammatory effect in LPS-induced microglial cells via the inhibition of the mitogen-activated protein kinase (MAPK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway and the activation of the nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. In the LPS-treated in vivo mouse models, the increased expression of ionized calcium binding adaptor molecule 1 (Iba-1), which indicates microglial activity, was markedly decreased upon treatment with CCL01 (50 and 200 mg kg^-1) in the hippocampus and cortex areas of the mouse brains in comparison with the LPS-injected group. In addition, the groups to which CCL01 was administered had significantly decreased plasma levels of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in the LPS-injected mouse models. Our data suggest that CCL01 may be a potential anti-neuroinflammatory agent that can prevent microglia overactivation, and it could be useful for developing functional foods.

Neuroprotective Effect of Clobenpropit against Lipopolysaccharide-Induced Cognitive Deficits via Attenuating Neuroinflammation and Enhancing Mitochondrial Functions in Mice

Clobenpropit (CLO), an antagonist on histamine H₃ receptors (HH3R), has been shown to protect NMDA-induced neuronal necrosis in cortical neuronal cell culture from rats. In this work, we explored its potential on lipopolysaccharide (LPS)-induced memory deficits, neuroinflammation, and mitochondrial dysfunction in mice. CLO (1 and 3 mg/kg, p.o.) was treated continually for 30 days, and neurotoxicity was induced by four doses of LPS (250 µg/kg, i.p.). The radial arm maze (RAM) was used to access memory behaviors. After the REM test, brain tissue was collected from each mouse to estimate pro-inflammatory cytokines (TNFα and IL6), anti-inflammatory cytokines (TGF-β1 and IL-10), cyclooxygenase-2 (COX 2), and mitochondrial respiratory chain complex (MRCC- I, II and IV) enzymes. CLO treatment reversed the LPS-induced behavioral deficits by a significant reduction in time taken to consume all five bites (TTB), working memory error (WME), and reference memory error (REM) in the REM test. Regarding neuroinflammation, it attenuated the release of COX, TNF-α, and IL-6, and augmented TGF-β1 and IL-10 levels in the brain. Reversal of LPS-induced brain MRCC (I, II, and IV) levels also resulted with CLO treatment. From these findings, CLO promises neuroprotection against LPS-induced cognitive deficits by ameliorating neuroinflammation and restoring the MRCC enzymes in mice.

Hyperoside Attenuate Inflammation in HT22 Cells via Upregulating SIRT1 to Activities Wnt/β-Catenin and Sonic Hedgehog Pathways

Neuroinflammation plays important roles in the pathogenesis and progression of altered neurodevelopment, sensorineural hearing loss, and certain neurodegenerative diseases. Hyperoside (quercetin-3-O-β-D-galactoside) is an active compound isolated from Hypericum plants. In this study, we investigate the protective effect of hyperoside on neuroinflammation and its possible molecular mechanism. Lipopolysaccharide (LPS) and hyperoside were used to treat HT22 cells. The cell viability was measured by MTT assay. The cell apoptosis rate was measured by flow cytometry assay. The mRNA expression levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) were determined by quantitative reverse transcription polymerase chain reaction. The levels of oxidative stress indices superoxide dismutase (SOD), reactive oxygen species (ROS), catalase (CAT), glutathione (GSH), and malondialdehyde (MDA) were measured by the kits. The expression of neurotrophic factor and the relationship among hyperoside, silent mating type information regulation 2 homolog-1 (SIRT1) and Wnt/β-catenin, and sonic hedgehog was examined by western blotting. In the LPS-induced HT22 cells, hyperoside promotes cell survival; alleviates the level of IL-1β, IL-6, IL-8, TNF-α, ROS, MDA, Bax, and caspase-3; and increases the expression of CAT, SOD, GSH, Bcl-2, BDNF, TrkB, and NGF. In addition, hyperoside upregulated the expression of SIRT1. Further mechanistic investigation showed that hyperoside alleviated LPS-induced inflammation, oxidative stress, and apoptosis by upregulating SIRT1 to activate Wnt/β-catenin and sonic hedgehog pathways. Taken together, our data suggested that hyperoside acts as a protector in neuroinflammation.