(+)-Catechin Alleviates CCI-Induced Neuropathic Pain in Rats by Modulating the IL34/CSFIR Axis and Attenuating the Schwann Cell-Macrophage Cascade Response in the DRG

The aim of this study was to investigate the potential therapeutic applications of (+)-catechin in the treatment of neuropathic pain. In vivo study, 32 SD rats were randomly divided into four groups: sham group, chronic constriction injury (CCI) group, CCI + ibuprofen group and CCI+ (+)-catechin group. They were subjected to behavioural tests, ELISA, immunohistochemistry and Western blotting. The mechanisms involved were investigated using specific inhibitors in cell experiments. Results of in vivo experiments showed that (+)-catechin could reduce the cold sensitivity pain in a rat model of CCI; ELISA and immunohistochemistry results showed that (+)-catechin could decrease the levels of IL-8, IL-6, TNF-α, CCL2 and CCL5 in serum and the expression levels of nNOS, COX2, IL6, TNF-α, IBA-1 and CSF1R in DRG of CCI rats. Finally, western blot confirmed that (+)-catechin could diminish the levels of IL-34/CSF1R/JAK2/STAT3 signalling pathway in DRG of CCI rats. In vitro studies showed that (+)-catechin reduced IL-34 secretion in LPS-induced RSC96 cells. Meanwhile, (+)-catechin administration in LPS-induced Schwann cell-conditioned medium (L-CM) significantly inhibited the proliferation and migration of RAW264.7 cells; in addition, L-CM+(+)-catechin reduced the activation of the CSF1R/JAK2/STAT3 signalling pathway. (+)-Catechin attenuated the Schwann cell-macrophage cascade response in the DRG by modulating the IL34/CSFIR axis and inhibiting activation of the JAK2/STAT3 pathway, thereby attenuating CCI-induced neuropathic pain in rats.

Unveiling the interplay of AMPK/SIRT1/PGC-1α axis in brain health: Promising targets against aging and NDDs

The escalating prevalence of neurodegenerative diseases (NDDs) within an aging global population presents a pressing challenge. The multifaceted pathophysiological mechanisms underlying these disorders, including oxidative stress, mitochondrial dysfunction, and neuroinflammation, remain complex and elusive. Among these, the AMPK/SIRT1/PGC-1α pathway emerges as a pivotal network implicated in neuroprotection against these destructive processes. This review sheds light on the potential therapeutic implications of targeting this axis, specifically emphasizing the promising role of flavonoids in mitigating NDD-related complications. Expanding beyond conventional pharmacological approaches, the exploration of non-pharmacological interventions such as exercise and calorie restriction (CR), coupled with the investigation of natural compounds, offers a beacon of hope. By strategically elucidating the intricate connections within these pathways, this review aims to pave the ways for novel multi-target agents and interventions, fostering a renewed optimism in the quest to combat and manage the debilitating impacts of NDDs on global health and well-being.

Anti-Neuroinflammatory Effects of Arecae pericarpium on LPS-Stimulated BV2 Cells

Arecae pericarpium (AP), the fruit peel of the betel palm, is a traditional Oriental herbal medicine. AP is used to treat various diseases and conditions, such as ascites, edema, and urinary retention, in traditional Korean medicine. Recent studies have demonstrated its anti-obesity and antibacterial effects; however, its anti-neuroinflammatory effects have not yet been reported. Therefore, we investigated the anti-neuroinflammatory effects of AP on lipopolysaccharide (LPS)-stimulated mouse microglia in this study. To determine the anti-neuroinflammatory effects of AP on BV2 microglial cells, we examined the production of nitric oxide (NO) using Griess assay and assessed the mRNA expression levels of inflammatory mediators, such as inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, and pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, using a real-time reverse transcription-polymerase chain reaction. Furthermore, we determined the levels of mitogen-activated protein kinases and IκBα via Western blotting to understand the regulating mechanisms of AP. AP treatment decreased NO production in LPS-stimulated BV2 cells. Additionally, AP suppressed the expression of iNOS and COX-2 and the production of pro-inflammatory cytokines. AP also inhibited the activation of p38 and nuclear factor-kappa B (NF-κB) in LPS-stimulated BV2 cells. Therefore, AP exerts anti-neuroinflammatory effects via inactivation of the p38 and NF-κB pathways.

Mitigating neuroinflammation in Parkinson's disease: Exploring the role of proinflammatory cytokines and the potential of phytochemicals as natural therapeutics

Parkinson's disease (PD) is one of the most prevalent neuroinflammatory illnesses, characterized by the progressive loss of neurons in the brain. Proinflammatory cytokines play a key role in initiating and perpetuating neuroinflammation, which can lead to the activation of glial cells and the deregulation of inflammatory pathways, ultimately leading to permanent brain damage. Currently, available drugs for PD mostly alleviate symptoms but do not target underlying inflammatory processes. There is a growing interest in exploring the potential of phytochemicals to mitigate neuroinflammation. Phytochemicals such as resveratrol, apigenin, catechin, anthocyanins, amentoflavone, quercetin, berberine, and genistein have been studied for their ability to scavenge free radicals and reduce proinflammatory cytokine levels in the brain. These plant-derived compounds offer a natural and potentially safe alternative to conventional drugs for managing neuroinflammation in PD and other neurodegenerative diseases. However, further research is necessary to elucidate their underlying mechanisms of action and clinical effectiveness. So, this review delves into the pathophysiology of PD and its intricate relationship with proinflammatory cytokines, and explores how their insidious contributions fuel the disease's initiation and progression via cytokine-dependent signaling pathways. Additionally, we tried to give an account of PD management using existing drugs along with their limitations. Furthermore, our aim is to provide a thorough overview of the diverse groups of phytochemicals, their plentiful sources, and the current understanding of their anti-neuroinflammatory properties. Through this exploration, we posit the innovative idea that consuming nutrient-rich phytochemicals could be an effective approach to preventing and treating PD.

Quality assessment of Rheum species cultivated in Japan by focusing on M2 polarization of microglia

In traditional Japanese medicine, Rhei Rhizoma is used as a purgative, blood stasis-resolving and antipsychotic drug. The latter two properties are possibly related to anti-inflammatory effects. Microglia regulate inflammation in the central nervous system. M1 microglia induce inflammation, while M2 microglia inhibit inflammation and show neurotrophic effects. This study investigated the effects from water extracts of roots of cultivated Rheum species in Nagano Prefecture, Japan (strain C, a related strain to a Japanese cultivar, 'Shinshu-Daio'; and strain 29, a Chinese strain) and 3 kinds of Rhei Rhizoma available in the Japanese market, and also examined their constituents on the polarization of cultured microglia. All extracts significantly decreased M1 microglia, and strains C and 29 significantly increased M2 microglia. Furthermore, the extracts of both strains significantly increased the M2/M1 ratio. Among the constituents of Rhei Rhizoma, ( +)-catechin (2), resveratrol 4'-O-β-D-(6″-O-galloyl) glucopyranoside (5), isolindleyin (8), and physcion (15) significantly increased the M2/M1 ratio. The contents of the constituents in water extract of each strain were quantified using HPLC. The extracts of strains C and 29 contained relatively large amounts of 2 and 5; and 2, 8, and 15, respectively. This study showed the water extracts of roots of cultivated Rheum strains in Japan had the effects of M2 polarization of microglia, suggesting that these strains become the candidate to develop anti-inflammatory Rhei Rhizoma. Moreover, the suitable chemical composition to possess anti-inflammatory activity in the brain was clarified for the future development of new type of Rhei Rhizoma.

Keratin8 Deficiency Aggravates Retinal Ganglion Cell Damage Under Acute Ocular Hypertension

Purpose

Keratin 8/18 (KRT8/18), paired members of the intermediate filament family, have shown vital functions in regulating physiological activities more than supporting the mechanic strength for cells and organelles. However, the KRT8/18 presence in retinal ganglion cells (RGCs) and functions on neuroprotection in a mouse model of acute ocular hypertension (AOH) are unknown and worthy of exploration.

Methods

We identified the existence of KRT8/18 in normal human and mouse retinas and primary RGCs. KRT8/18 levels were detected after AOH modeling. The adeno-associated virus (AAV) system was intravitreally used for selective KRT8 knockdown in RGCs. The histological changes, the loss and dysfunction of RGCs, and the gliosis in retinas were detected. The markers of cell apoptosis and MAPK pathways were investigated.

Results

KRT8/18 existed in all retinal layers and was highly expressed in RGCs, and they increased after AOH induction. The KRT8 knockdown in RGCs caused no histopathological changes and RGC loss in retinas without AOH modeling. However, after the KRT8 deficiency, AOH significantly promoted the loss of whole retina and inner retina thickness, the reduction, apoptosis, and dysfunction of RGCs, and the glial activation. Besides, downregulated Bcl-2 and upregulated cleaved-Caspase 3 were found in the AOH retinas with KRT8 knockdown, which may be caused by the increased phosphorylation level of MAPK pathways (JNK, p38, and ERK).

Conclusions

The KRT8 deficiency promoted RGC apoptosis and neurodegeneration by abnormal activation of MAPK pathways in AOH retinas. Targeting KRT8 may serve as a novel treatment for saving RCGs from glaucomatous injuries.

(-)-Epicatechin gallate prevents inflammatory response in hypoxia-activated microglia and cerebral edema by inhibiting NF-κB signaling

High-altitude cerebral edema (HACE), a potentially lethal disease, is associated with a time-dependent exposure to altitude-related hypobaric hypoxia (HH) and has reportedly been associated with microglia hyperactivation. Catechins are substances with good antioxidant properties, among which (-)-epigallocatechin gallate (EGCG) may play a neuroprotective role through the inhibition of microglia overactivation; however, the function of its analog- (-)-epicatechin gallate (ECG)-requires further elucidation. The aim of the present study was to investigate whether ECG prevented HACE by inhibiting HH-activated microglia. Primary microglia exposed to lipopolysaccharide (LPS)/ATP were co-treated with EGCG, ECG, and (-)-epigallocatechin, and ECG and EGCG exerted significant anti-inflammatory and neuroprotective effects. ECG inhibited the NF-κB pathway to prevent the activation of microglia induced by 1% O₂. In addition, ECG ameliorated the increase in brain water content and aquaporin 4 expression induced by HH in mice. ECG also reduced the number of Iba1⁺ microglia in the brain, the release of proinflammatory factors, and the recruitment of microglia to blood vessels in HH-exposed mice. The outcomes of the present study revealed that ECG alleviated hypoxic hyperactivated microglia, reduced the neuroinflammation and blood-brain barrier permeability, and prevented HACE by inhibiting NF-κB signaling.

Metabolism of Paeoniae Radix Rubra and its 14 constituents in mice

Objective: Paeoniae Radix Rubra (PRR) is a commonly used traditional Chinese medicine with the effects of clearing away heat, cooling the blood, and relieving blood stasis. To 1) elucidate the metabolites and metabolic pathways of PRR and its 14 main constituents in mice and 2) reveal the possible origins of the known effective forms of PRR and their isomers, the metabolism of PRR in mice was systematically studied for the first time.

Methods: PRR and its 14 constituents were administered to mice by gavage once a day for seven consecutive days, respectively. All urine and feces were collected during the 7 days of dosing, and blood was collected at 1 h after the last dose. Metabolites were detected and identified using high performance liquid chromatography with diode array detector and combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry (HPLC-DAD-ESI-IT-TOF-MSⁿ).

Results: In total, 23, 16, 24, 17, 18, 30, 27, 17, 22, 17, 33, 3, 8, 24, and 31 metabolites of paeoniflorin, albiflorin, oxypaeoniflorin, benzoylpaeoniflorin, hydroxybenzoylpaeoniflorin, benzoyloxypaeoniflorin, galloylpaeoniflorin, lactiflorin, epicatechin gallate, catechin gallate, catechin, ellagic acid, 3,3′-di-O-methylellagic acid, methylgallate, and PRR were respectively identified in mice; after eliminating identical metabolites, a total of 195 metabolites remained, including 8, 11, 25, 17, 18, 30, 27, 17, 21, 17, 1, 2, 8, 20, and 20 newly identified metabolites, respectively. The metabolic reactions of PRR and its 14 main constituents in mice were primarily methylation, hydrogenation, hydrolysis, hydroxylation, glucuronidation, and sulfation.

Conclusion: We elucidated the metabolites and metabolic pathways of PRR and its 14 constituents (e.g., paeoniflorin, catechin, ellagic acid, and gallic acid) in mice and revealed the possible origins of the 10 known effective forms of PRR and their isomers. The findings are of great significance to studying the mechanism of action and quality control of PRR.

Quercus acuta Thunb. Suppresses LPS-Induced Neuroinflammation in BV2 Microglial Cells via Regulating MAPK/NF-κB and Nrf2/HO-1 Pathway

Microglial activation-mediated neuroinflammation is associated with the pathogenesis of neurodegenerative disorders. Therefore, the management of microglial cell activation and their inflammatory response is an important therapeutic approach for preventing neurodegenerative diseases. Quercus acuta Thunb. (QA) (Fagaceae) is a tree found in Korea, China, and Japan. The current study investigated the anti-neuroinflammatory effects of QA and its mechanism of action in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Pretreatment with a methanol extract of dried QA stems (QAE) inhibited the production of nitric oxide and proinflammatory cytokines and decreased the expression of inducible nitric oxide synthase, cyclooxygenase-2 in LPS-stimulated BV2 microglial cells. Furthermore, it inhibited the phosphorylation and degradation of inhibitory κBα and decreased the nuclear translocation and phosphorylation of nuclear factor-κB (NF-κB). Moreover, QAE inhibited the phosphorylation of extracellular signal-regulated kinase, p38 and c-Jun N-terminal kinase, which is known as mitogen-activated protein kinase (MAPK). Additionally, QAE treatment increased heme oxygenase-1 (HO-1) expression by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling, thereby ameliorating LPS-induced intracellular hydrogen peroxide production. Finally, it was found that catechin and taxifolin, two phytochemicals of QAE, also reduced the expression of inflammatory mediators. These findings suggest that QA is beneficial for preventing microglia-mediated neuroinflammatory response through the inhibition of NF-κB, MAPK and the activation of Nrf2/HO-1 signaling pathways.

Neuronutraceuticals Combating Neuroinflammaging: Molecular Insights and Translational Challenges—A Systematic Review

Neuropathologies, such as neuroinflammaging, have arisen as a serious concern for preserving the quality of life due to the global increase in neurodegenerative illnesses. Nowadays, neuronutraceuticals have gained remarkable attention. It is necessary to investigate the bioavailability, off-target effects, and mechanism of action of neuronutraceuticals. To comprehend the comprehensive impact on brain health, well-designed randomized controlled trials testing combinations of neuronutraceuticals are also necessary. Although there is a translational gap between basic and clinical research, the present knowledge of the molecular perspectives of neuroinflammaging and neuronutraceuticals may be able to slow down brain aging and to enhance cognitive performance. The present review also highlights the key emergent issues, such as regulatory and scientific concerns of neuronutraceuticals, including bioavailability, formulation, blood–brain permeability, safety, and efficacy.

Oxidative stress in the pathophysiology of type 2 diabetes and related complications: Current therapeutics strategies and future perspectives

Type 2 diabetes (T2DM) is a persistent metabolic disorder rising rapidly worldwide. It is characterized by pancreatic insulin resistance and β-cell dysfunction. Hyperglycemia induced reactive oxygen species (ROS) production and oxidative stress are correlated with the pathogenesis and progression of this metabolic disease. To counteract the harmful effects of ROS, endogenous antioxidants of the body or exogenous antioxidants neutralise it and maintain bodily homeostasis. Under hyperglycemic conditions, the imbalance between the cellular antioxidant system and ROS production results in oxidative stress, which subsequently results in the development of diabetes. These ROS are produced in the endoplasmic reticulum, phagocytic cells and peroxisomes, with the mitochondrial electron transport chain (ETC) playing a pivotal role. The exacerbated ROS production can directly cause structural and functional modifications in proteins, lipids and nucleic acids. It also modulates several intracellular signaling pathways that lead to insulin resistance and impairment of β-cell function. In addition, the hyperglycemia-induced ROS production contributes to micro- and macro-vascular diabetic complications. Various in-vivo and in-vitro studies have demonstrated the anti-oxidative effects of natural products and their derived bioactive compounds. However, there is conflicting clinical evidence on the beneficial effects of these antioxidant therapies in diabetes prevention. This review article focused on the multifaceted role of oxidative stress caused by ROS overproduction in diabetes and related complications and possible antioxidative therapeutic strategies targeting ROS in this disease.

Mechanistic insight into the role of metformin in Alzheimer's disease

Alzheimer's disease (AD), a type of dementia, is characterized by progressive memory decline and cognition impairment. Despite the considerable body of evidence regarding AD pathophysiology, current therapies merely slow down the disease progression, and a comprehensive therapeutic approach is unavailable. Accordingly, finding an efficient multifunctional remedy is necessary to blunt the increasing rate of AD incidence in the upcoming years. AD shares pathophysiological similarities (e.g., impairment of cognitive functions, insulin sensitivity, and brain glucose metabolism) with noninsulin-dependent diabetes mellitus (NIDDM), which offers the utilization of metformin, a biguanide hypoglycemic agent, as an alternative therapeutic approach in AD therapy. Emerging evidence has revealed the impact of metformin in patients suffering from AD. It has been described that metformin employs multiple mechanisms to improve cognition and memory impairment in pre-clinical AD models, including reduction of hippocampal amyloid-beta (Aβ) plaque and neurofibrillary tangles (NFTs) load, suppression of inflammation, amelioration of mitochondrial dysfunction and oxidative stress, restriction of apoptotic neuronal death, and induction of neurogenesis. This review discusses the pre-clinical evidence, which may shed light on the role of metformin in AD and provide a more comprehensive mechanistic insight for future studies in this area of research.

Flavonoids modulate AMPK/PGC-1α and interconnected pathways toward potential neuroprotective activities

As progressive, chronic, incurable and common reasons for disability and death, neurodegenerative diseases (NDDs) are significant threats to human health. Besides, the increasing prevalence of neuronal gradual degeneration and death during NDDs has made them a global concern. Since yet, no effective treatment has been developed to combat multiple dysregulated pathways/mediators and related complications in NDDs. Therefore, there is an urgent need to create influential and multi-target factors to combat neuronal damages. Accordingly, the plant kingdom has drawn a bright future. Among natural entities, flavonoids are considered a rich source of drug discovery and development with potential biological and medicinal activities. Growing studies have reported multiple dysregulated pathways in NDDs, which among those mediator AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) play critical roles. In this line, critical role of flavonoids in the upregulation of AMPK/PGC-1α pathway seems to pave the road in the treatment of Alzheimer's disease (AD), Parkinson's disease (PD), aging, central nervous system (brain/spinal cord) damages, stroke, and other NDDs. In the present study, the regulatory role of flavonoids in managing various NDDs has been shown to pass through AMPK/PGC-1α signaling pathway.

Flavonoids as potential phytotherapeutics to combat cytokine storm in SARS-CoV-2

Emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, COVID-19, has become the global panic since December 2019, which urges the global healthcare professionals to identify novel therapeutics to counteract this pandemic. So far, there is no approved treatment available to control this public health issue; however, a few antiviral agents and repurposed drugs support the patients under medical supervision by compromising their adverse effects, especially in emergency conditions. Only a few vaccines have been approved to date. In this context, several plant natural products-based research studies are evidenced to play a crucial role in immunomodulation that can prevent the chances of infection as well as combat the cytokine release storm (CRS) generated during COVID-19 infection. In this present review, we have focused on flavonoids, especially epicatechin, epigallocatechin gallate, hesperidin, naringenin, quercetin, rutin, luteolin, baicalin, diosmin, ge nistein, biochanin A, and silymarin, which can counteract the virus-mediated elevated levels of inflammatory cytokines leading to multiple organ failure. In addition, a comprehensive discussion on available in silico, in vitro, and in vivo findings with critical analysis has also been evaluated, which might pave the way for further development of phytotherapeutics to identify the potential lead candidatetoward effective and safe management of the SARS-CoV-2 disease.

Neuroprotective effects of Levisticum officinale on LPS-induced spatial learning and memory impairments through neurotrophic, anti-inflammatory, and antioxidant properties

Levisticum officinale (Apiaceae) has been identified as a medicinal plant in traditional medicine, with the anti-inflammatory, antioxidant, and anticholinesterase activities. The present study aims to evaluate the effects of Levisticum officinale extract (LOE) on lipopolysaccharide (LPS)-induced learning and memory deficits and to examine its potential mechanisms. LOE was administered to adult male Wistar rats at doses of 100, 200, and 400 mg kg-1 for a week. Later, LPS was intraperitoneally injected at a dose of 1 mg kg-1 to induce neuroinflammation, and treatment with LOE continued for 3 more weeks. Behavioral, biochemical, and molecular analyses were performed at the end of the experiment. Moreover, quantitative immunohistochemical assessments of the expression of Ki-67 (intracellular proliferation marker) in the hippocampus were performed. The results revealed that LPS injection caused spatial memory impairment in the rats. Daily LOE treatment at applied doses for 4 weeks attenuated spatial learning and memory deficits in LPS-injected rats. Furthermore, LPS significantly increased the mRNA expression level of interleukin-6 in the hippocampus, which was accompanied by decreased brain-derived neurotrophic factor (BDNF) mRNA expression levels. Moreover, LPS increased the levels of malondialdehyde, reduced the antioxidant enzyme activities of catalase and superoxide dismutase in the hippocampus, and impaired neurogenesis. However, pre-treatment with LOE at a dose of 100 mg kg-1 significantly reversed the LPS-induced changes, and improved neurogenesis. In conclusion, the beneficial effect of LOE on the improvement of learning and memory could be attributed to its anti-inflammatory and antioxidant activities, along with its ability to increase BDNF expression and neurogenesis in the hippocampus.

Neuroinflammation Mechanisms and Phytotherapeutic Intervention: A Systematic Review

Neuroinflammation is indicated in the pathogenesis of several acute and chronic neurological disorders. Acute lesions in the brain parenchyma induce intense and highly complex neuroinflammatory reactions with similar mechanisms among various disease prototypes. Microglial cells in the CNS sense tissue damage and initiate inflammatory responses. The cellular and humoral constituents of the neuroinflammatory reaction to brain injury contribute significantly to secondary brain damage and neurodegeneration. Inflammatory cascades such as proinflammatory cytokines from invading leukocytes and direct cell-mediated cytotoxicity between lymphocytes and neurons are known to cause "collateral damage" in models of acute brain injury. In addition to degeneration and neuronal cell loss, there are secondary inflammatory mechanisms that modulate neuronal activity and affect neuroinflammation which can even be detected at the behavioral level. Hence, several of health conditions result from these pathogenetic conditions which are underlined by progressive neuronal function loss due to chronic inflammation and oxidative stress. In the first part of this Review, we discuss critical neuroinflammatory mediators and their pathways in detail. In the second part, we review the phytochemicals which are considered as potential therapeutic molecules for treating neurodegenerative diseases with an inflammatory component.

Anti-Inflammatory Activity of Oligomeric Proanthocyanidins Via Inhibition of NF-κB and MAPK in LPS-Stimulated MAC-T Cells

Oligomeric proanthocyanidins (OPCs), classified as condensed tannins, have significant antioxidation, anti-inflammation and anti-cancer effects. This study was performed to investigate the anti-inflammatory effects of OPCs and the mechanism underlying these effects in lipopolysaccharide (LPS)-stimulated bovine mammary epithelial cells (MAC-T). Real-time PCR and ELISA assays indicated that OPC treatment at 1, 3 and 5 μg/ml significantly reduced the mRNA and protein, respectively, of oxidant indicators cyclooxygenase-2 (COX-2) (p < 0.05) and inducible nitric oxide synthase (iNOS) (p < 0.01) as well as inflammation cytokines interleukin (IL)-6 (p < 0.01), IL-1β (p < 0.01) and tumor necrosis factor-α (TNF-α) (p < 0.05) in LPS-induced MAC-T cells. Moreover, OPCs downregulated LPSinduced phosphorylation of p65 and inhibitor of nuclear factor kappa B (NF-κB) (IκB) in the NF-κB signaling pathway (p < 0.01), and they inhibited p65 translocation from the cytoplasm to the nucleus as revealed by immunofluorescence test and western blot. Additionally, OPCs decreased phosphorylation of p38, extracellular signal regulated kinase and c-jun NH₂-terminal kinase in the MAPK signaling pathway (p < 0.01). In conclusion, the anti-inflammatory and antioxidant activities of OPCs involve NF-κB and MAPK signaling pathways, thus inhibiting expression of pro-inflammatory factors and oxidation indicators. These findings provide novel experimental evidence for the further practical application of OPCs in prevention and treatment of bovine mastitis.

Spatholobi Caulis dispensing granule reduces deep vein thrombus burden through antiinflammation via SIRT1 and Nrf2

BACKGROUND

Deep vein thrombosis (DVT) is a kind of blood stasis syndrome. Spatholobi Caulis (SC) has been widely used for the treatment of blood stasis syndrome in China, but the underlying mechanism remains poorly understood.

PURPOSE

The aim of present study was to investigate the anti-DVT mechanism of Spatholobi Caulis dispensing granule (SCDG).

STUDY DESIGN/METHODS

A rat model of inferior vena cava (IVC) stenosis-induced DVT and a cell model of oxygen-glucose deprivation (OGD) were performed. Rats were orally administered with SCDG solution once daily for seven consecutive days. IVC stenosis-induced DVT was operated on the sixth day. Thrombi were harvested and weighed on the seventh day. Pathological changes were observed by hematoxylin-eosin (HE) staining. Tumor necrosis factor (TNF)-α and interleukin (IL)-1β of serum were analyzed by enzyme-linked immunosorbent assay. C-reactive protein (CRP) was measured with turbidimetric immunoassay. Protein expressions in thrombosed IVCs and/or OGD-stimulated EA. hy926 cells were evaluated by western blot and/or immunofluorescence analyses.

RESULTS

SCDG dramatically decreased thrombus weight. SCDG decreased tissue factor (TF) protein expression, inflammatory cells influxes in thrombosed vein wall and serum levels of inflammatory cytokines and CRP. Further, SCDG up-regulated Sirtuin 1 (SIRT1) protein expression and down-regulated acetylated-NF-κB p65 (Ace-p65) protein expression. Moreover, SCDG up-regulated nuclear factor-erythroid 2 related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) protein expressions, and down-regulated phosphorylated-NF-κB p65 (p-p65) protein expression. In the OGD cell model, SCDG medicated serum decreased the protein expression of TF. SCDG medicated serum enhanced SIRT1 protein expression and reduced Ace-p65 nuclear protein expression. SCDG medicated serum promoted protein expressions of nuclear Nrf2 and total HO-1, and inhibited translocation of p65. Furthermore, inhibiting SIRT1 and Nrf2 reversed the protective effect of SCDG medicated serum on OGD-induced EA. hy926 cells.

CONCLUSION

SCDG may prevent DVT through antiinflammation via SIRT1 and Nrf2.

Effect of dietary inclusion of almond fruit on sexual behavior, arginase activity, pro-inflammatory, and oxidative stress markers in diabetic male rats

This study was designed to examine the effect of almond-included diets on sexual behavior, arginase activity, and pro-inflammatory markers in diabetic male rats. Forty-two male rats were divided into seven groups (n = 6). Diabetes was triggered via a single dose intraperitoneal injection of streptozotocin (50 mg/kg). Diabetes was confirmed 72 hr after STZ induction, and animals with blood glucose ≥ 250 mg/dl were considered diabetic and used for the experiment. The effects of almond-supplemented diets on glucose level, sexual function, NF-κB and TNF-α levels, arginase and purinergic enzyme activities, and levels of oxidative stress markers were assessed. A significant decrease in sexual activities with a simultaneous increase in pro-inflammatory markers, arginase and purinergic enzyme activities as well as TBARS and ROS levels was observed in diabetic rats. Interestingly, treatment with supplemented diets ameliorated the effects. Conclusively, intake of almonds could prevent the risk of erectile dysfunction in diabetic subjects. PRACTICAL APPLICATIONS: Intake of diets rich in fruits, nuts, and vegetables has been reported to reduce the risk of metabolic syndrome. Here, we investigate the effect of dietary inclusion of almond fruit on sexual behavior, arginase activity, oxidative stress, and pro-inflammatory markers in diabetic male rats. Interestingly, data generated from this work reveal that the supplemented diets enhanced sexual activities, and reduced oxidative stress and pro-inflammatory markers in diabetic male rats. Thus, consumption of almond (drupe and seed) could prevent/reduce the erectile dysfunction in individual with diabetes.

Identifying potential active components of walnut leaf that action diabetes mellitus through integration of UHPLC-Q-Orbitrap HRMS and network pharmacology analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Walnut leaf (WL) is a hypoglycemic herbal medication with blood glucose-lowering activity that can affect diabetes mellitus (DM). However, the active components of WL and the mechanisms by which these compounds affect DM are unclear.

AIM OF STUDY

This study aimed to determine these effective ingredients and elucidate the potential mechanisms by which they affect DM via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) coupled with network pharmacology analysis.

MATERIALS AND METHODS

First, UHPLC-Q-Orbitrap HRMS was utilized to identify components of WL. Second, the putative targets of the components were identified and predicted based on chemical similarity and online databases. Third, the key candidate targets and potential active components were identified through topological analysis of a component-disease target interaction network. Finally, interactions between active components and therapeutic targets were confirmed by molecular docking analysis.

RESULTS

One hundred and thirty components were identified in WL, among which 38 were considered potentially bioactive, as they showed hypoglycemic effects. Among these 38, 8 key active components possessed high similarities and shared 4 targets with approved drugs. These findings were confirmed by molecular docking analysis.

CONCLUSION

The approach combining UHPLC-Q-Orbitrap HRMS with network pharmacology analysis is a rapid and effective tool to identify potentially bioactive constituents in medicinal plants and prescriptions.

Spirogyra neglecta Aqueous Extract Attenuates LPS-Induced Renal Inflammation

Spirogyra neglecta (SN), commonly named "Tao" in Thai, is a genus of filamentous green macroalgae. SN contains polyphenols such as isoquercetin, catechin, hydroquinone and kaempferol. These constituents exhibit beneficial effects including anti-oxidant, anti-gastric ulcer, anti-hyperglycaemia and anti-hyperlipidaemia in both in vitro and in vivo models. Whether SN extract (SNE) has an anti-inflammatory effect in vivo remains unclear. This study examined the effect of SNE on renal function and renal organic transport in lipopolysaccharide (LPS)-induced renal inflammation in rats. Rats were randomised and divided into normal saline (NS), NS supplemented with 1000 mg/kg body weight (BW) of SNE (NS + SNE), intraperitoneally injected with 12 mg/kg BW of LPS and LPS treated with 1000 mg/kg BW of SNE (LPS + SNE). Biochemical parameters in serum and urine, lipid peroxidation concentration, kidney function and renal organic anion and cation transports were determined. LPS-injected rats developed renal injury and inflammation by increasing urine microalbumin, total malondialdehyde (MDA) and inflammatory cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β protein expression, respectively. In addition, uptake of renal organic anion, [³H]-oestrone sulphate (ES), was reduced in LPS-injected rats together with increased expression of organic anion transporter 3 (Oat3). However, the renal injury and inflammation, as well as impaired Oat3 function and protein expression, were restored in LPS + SNE rats. Accordingly, SNE could be developed as nutraceutical product to prevent inflammation-induced nephrotoxicity.

Pharmacological evidence of Vitex thyrsiflora, Entandrophragma cylindricum, and Anonidium mannii used for the management of inflammation in Cameroon

Background Inflammation is the most common health problem faced in life relating to a vast number of diseases. The present study evaluated the pharmacological effect of three plants (Vitex thyrsiflora, Entandrophragma cylindricum, and Anonidium mannii) commonly used in the Cameroon pharmacopeia for the management of inflammatory response. Methods The pharmacological effect was characterized by the antioxidant capacity, anti-inflammatory, analgesic, and antipyretic properties of the ethanol extracts of the three plants. Antioxidant capacity was determined using total phenolic content, total flavonoid content, hydrogen peroxide, ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging assays. Anti-inflammatory activity was evaluated in vitro by protein denaturation and hypotonic-induced hemolysis methods and in vivo by carrageenan paw edema method. Analgesic and antipyretic activities were studied in vivo using acetic acid-induced writhing and brewer's yeast-induced hyperpyrexia models. Results All selected extracts showed high phenolic (15.93-64.45 mgCAE/g) and flavonoid (336.03-1053.48 mgCAE/g) contents and high ferric reducing power (288.75-364.91 mgCAE/g). These extracts exhibited good DPPH (IC50 = 0.30-1.65 μg/mL), ABTS (IC50 = 0.52-1.90 μg/mL), and H2O2 (IC50 = 1.40-3.55 μg/mL) radical scavenging activities. All extracts inhibited protein denaturation (6.79-82.27%) and protected the erythrocyte membrane from lysis induced by hypotonic solution (18.90-88.00%). The extracts significantly reduced dose-dependent paw edema (p < 0.05), fever, and abdominal writhing (p < 0.001) especially at 400 mg/kg. Conclusions All extracts exhibited interesting antioxidant properties, as well as significant anti-inflammatory, analgesic, and antipyretic effects.

Catechins reduce inflammation in lipopolysaccharide-stimulated dental pulp cells by inhibiting activation of the NF-κB pathway

AIM

To ascertain the anti-inflammation mechanism of catechins in lipopolysaccharide-treated human dental pulp cells (HDPCs).

METHODS

Expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 was measured using quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assays. The anti-inflammatory mechanism was explored by examining activation of nuclear factor-kappa B (NF-κB) signaling using qPCR, Western blotting, and immunofluorescence staining.

RESULTS

Human dental pulp cells proliferation was not affected by treatment with epigallocatechin (ECG) or epigallocatechin 3-gallate (EGCG). mRNA expression of the pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 was decreased significantly in ECG- and EGCG-treated HDPCs. Subsequently, the effects of ECG and EGCG upon activation of NF-κB signaling were evaluated by Western blotting and immunofluorescence staining. Expression of p-p65 protein in HDPCs treated with ECG, EGCG, or an NF-κB inhibitor (Bay 11-7082) was lower than that in HDPCs treated with lipopolysaccharide, data that were consistent with the location of p65 protein according to immunofluorescence staining.

CONCLUSIONS

Catechin could reduce lipopolysaccharide-stimulated inflammation in HDPCs by inhibiting activation of the NF-κB pathway.

Technological Potential of Avocado Oil: Prospective Study Based on Patent Documents

BACKGROUND

Avocado (Persea Americana, Mill.), belonging to the Lauraceae family, is considered a tropical fruit originating in Central America, with Mexico being the largest producer in the world. The fruit stands out for its economic potential and high nutritional value and its oil has good commercial value, however, its production is still incipient, being mainly used by the pharmaceutical and cosmetic industries. Despite producing a significant amount of oil, the avocado seed is still considered a by-product of fruit processing.

METHODS

Thus, the objective of this work was to evaluate the technological potential of the oil obtained from the avocado and avocado seed through the research and analysis of patent documents available worldwide, in order to identify the main countries that have the technology researched as well as, the main areas of application. We revised all the patents related to acquisition, application and the use of avocado oil. For this, a search was carried out for the database of the Derwent Innovation Index (DII), which compiles the collection of documents published around the world.

RESULTS

A total of 144 patent documents were identified, which were evaluated for the country of origin of thepublisher, the type of thepublisher, inventors, rate of publication over time and areas of application. There has been an increase in the number of patents producded as of 2011, which proves it to be a current and interesting technology. The main countries were the United States and the European Union.

CONCLUSION

The documents identified referred to different processes applied to obtain oil, as well as the application for the development of new food, cosmetic and veterinary products. In this way, although incipient, the researched technology proved to be a promising area of research to be explored by universities and companies in view of the characteristics and potential of the product.

Green tea catechins inhibit microglial activation which prevents the development of neurological disorders

The over-activated microglial cells induce neuroinflammation which has the main role in neurological disorders. The over-activated microglia can disturb neuronal function by releasing inflammatory mediators leading to neuronal dysfunctions and death. Thus, inhibition of over-activated microglia may be an effective therapeutic approach for modulating neuroinflammation. Experimental studies have indicated anti-neuroinflammatory effects of flavonoids such as green tea catechins. The current research was aimed to review the effect of green tea catechins in inhibiting microglial cells, inflammatory cascades, and subsequent neurological diseases.

Curcumin Regulates Anti-Inflammatory Responses by JAK/STAT/SOCS Signaling Pathway in BV-2 Microglial Cells

Microglia play important physiological roles in central nervous system (CNS) homeostasis and in the pathogenesis of inflammatory brain diseases. Inflammation stimulates microglia to secrete cytokines and chemokines that guide immune cells to sites of injury/inflammation. Neuroinflammation is also strongly implicated in the pathogenesis of a number of neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease, for which nutritional intervention could represent a benefit due to a lack of clinically efficacious drugs. To this end, the anti-inflammatory mechanisms of several phytochemicals, including curcumin, have been extensively studied. The present experiments show that the administration of curcumin is able to increase the production of the anti-inflammatory cytokines, IL-4 and IL-10, in murine BV-2 microglial cells treated with lipopolysaccharide (LPS). Consistent with these data, curcumin stimulation upregulates the expression of Suppressors of cytokine signaling (SOCS)-1, whereas phosphorylation of the JAK2 and STAT3 was reduced. Taken together, these results provide evidence that curcumin is able to regulate neuroinflammatory reactions by eliciting anti-inflammatory responses in microglia through JAK/STAT/SOCS signaling pathway modulation.

Catechin ameliorates depressive symptoms in Sprague Dawley rats subjected to chronic unpredictable mild stress by decreasing oxidative stress

Catechin is an active ingredient of green tea. It is reported to inhibit corticosteroid-induced anxiety and depression-like symptoms. Considering the complex nature of depression, effects of catechin need to be studied in a clinically relevant depression model. The present study was designed to explore the antidepressant effect of catechin in Sprague Dawley rats subjected to chronic unpredictable mild stress (CUMS). Animals were subjected to CUMS and treated with (+)-catechin (50 mg/kg) or escitalopram (10 mg/kg) orally; a CUMS control and a vehicle control that was not exposed to CUMS were also established. Various stressors were applied daily in an unpredictable manner for 8 weeks achieve CUMS. Sucrose preference test were performed after 4 and 8 weeks and forced swim tests (FSTs) were conducted at weeks 4, 6 and 8. At the end of week 8, animals were sacrificed and the brain homogenate was studied for antioxidant parameters. Compared with the vehicle control, animals of the CUMS control group showed a significant decrease in sucrose intake. Catechin and escitalopram treatment significantly improved the sucrose intake compared with the CUMS control. A similar trend was observed in the FSTs, where catechin and escitalopram treatment significantly reduced the immobility time, and antioxidant parameters, including catalase, glutathione and superoxide dismutase levels were recovered in treated animals compared with the CUMS control. Thus, it was concluded that catechin reverses CUMS-induced depression in rats by ameliorating oxidative stress, which may help to develop a novel treatment for major depressive disorder.

Synergistically dual-functional nano eye-drops for simultaneous anti-inflammatory and anti-oxidative treatment of dry eye disease

We have developed a rapid and straightforward topical treatment method for dry eye disease (DED) using poly(catechin) capped-gold nanoparticles (Au@Poly-CH NPs) carrying amfenac [AF; a nonsteroidal anti-inflammatory drug (NSAID)] through effective attenuation of ocular surface tissue damage in dry eyes. A dual-targeted strategy based on ocular therapeutics was adopted to simultaneously block the cyclooxygenase enzymes-induced inflammation and reactive oxygen species (ROS)-induced oxidative stress, the primary two causes of DED. The self-assembled core-shell Au@Poly-CH NPs synthesized via a simple reaction between tetrachloroaurate(iii) and catechin possess a poly(catechin) shell (∼20 nm) on the surface of each Au NP (∼60 nm). The anti-oxidant and anti-inflammatory properties of AF/Au@Poly-CH NPs were evaluated by DCFH-DA and prostaglandin E2/VEGF assays, respectively. Our results demonstrate that Au@Poly-CH NPs not only act as an anti-oxidant to suppress ROS-mediated processes, but also serve as a drug carrier of AF for a synergistic effect on anti-inflammation. In vivo biocompatibility studies show good tolerability of AF/Au@Poly-CH NPs for potential use in the treatment of ocular surface pathologies. The dual-targeted therapeutic effects of AF/Au@Poly-CH NPs lead to rapid recovery from DED in a rabbit model. Au@Poly-CH NPs loaded with NSAIDs is a promising multifunctional nanocomposite for treating various inflammation- and oxidative stress-related diseases.

Constituents ofTalisia nervosawith Potential Utility against Metabolic Syndrome

This study is focused on the isolation and characterization of bioactive secondary metabolites from the ethanolic extract of stems of the Panamanian plant Talisia nervosa Radlk, through a series of target-based cellular assays related to the metabolic syndrome (MetS): a combination of type 2 Diabetes Mellitus (T2DM), hypercholesterolemia, inflammation, and obesity. Bioassay guided fractionation allowed the isolation of four known compounds: (-)-catechin (1), methyl gallate (2), ethyl gallate (3), and ß-D-glucopyranose,1,4,6-tris(3,4,5-trihydroxybenzoate) (4). This is the first report of (-)-catechin (1) and ß-D-glucopyranose,1,4,6-tris (3,4,5-trihydroxybenzoate) (4) from T. nervosa. Among the isolates, 1 activated PPARγ, but had no effect on PPARα. Compounds 2 -4 activated PPARα, PPARγ and LXR. Interestingly, 2 was stronger than 3 towards all three targets. Methyl gallate (2) showed the most potent effect toward both PPARα and PPARγ with an increase of 3.0 and 13-fold, respectively, while 4 was most potent in activating LXR with a fold induction of 5.3 at concentrations of 100 μg/mL. The nitric oxide (NO) production was reduced by compounds 2 and 3 with IC50values of 7.0 and 7.5 μg/mL, respectively. ß-D-glucopyranose,1,4,6-tris (3,4,5-trihydroxybenzoate) 4) did not cause a significant increase in adipogenesis despite its strong PPARγ agonistic action (8 6-fold increase) and may represent a good candidate for the treatment of MetS without the undesirable side effect of weight gain.

The Novel Neuroprotective Compound KMS99220 Has an Early Anti-neuroinflammatory Effect via AMPK and HO-1, Independent of Nrf2

We have previously reported a novel synthetic compound KMS99220 that prevented degeneration of the nigral dopaminergic neurons and the associated motor deficits, suggesting a neuroprotective therapeutic utility for Parkinson's disease. Microglia are closely associated with neuroinflammation, which plays a key role in the pathogenesis of neurodegenerative diseases. In this study, we investigated the effects of KMS99220 on the signaling involving AMP-activated protein kinase (AMPK) and heme oxygenase-1 (HO-1), the enzymes thought to regulate inflammation. KMS99220 was shown to elevate the enzyme activity of purified AMPK, and phosphorylation of cellular AMPK in BV2 microglia. It increased the level of HO-1, and this was attenuated by AMPK inhibitors. KMS99220 lowered phosphorylation of IκB, nuclear translocation of NFκB, induction of inducible nitric oxide synthase, and generation of nitric oxide in BV2 cells that had been challenged with lipopolysaccharide. This anti-inflammatory response involved HO-1, because both its pharmacological inhibition and knockdown of its expression abolished the response. The AMPK inhibitors also reversed the anti-inflammatory effects of KMS99220. The induction of HO-1 by KMS99220 occurred within 1 h, and this appeared not to involve the transcription factor Nrf2, because Nrf2 knockdown did not affect the compound's HO-1 inducing- and anti-inflammatory effects in this time window. These findings indicated that KMS99220 leads to AMPK-induced HO-1 expression in microglia, which in turn plays an important role in early anti-inflammatory signaling. Together with its neuroprotective property, KMS99220 may serve as a feasible therapeutic agent against neuroinflammation and neurodegeneration.

Dihydromyricetin Inhibits Lead-Induced Cognitive Impairments and Inflammation by the Adenosine 5'-Monophosphate-Activated Protein Kinase Pathway in Mice

Dihydromyricetin (DHM), a natural flavonoid derived from the medicinal and edible plant Ampelopsis grossedentata, exhibits antioxidant, antiapoptosis, antitumor, and anti-inflammatory bioactivities. This study evaluated the effects of DHM on Pb-induced neurotoxicity and explored the underlying mechanisms. DHM significantly ameliorated behavioral impairments of Pb-induced mice. It decreased the levels of lipid peroxidation and protein carbonyl and increased the activities of superoxide dismutase and catalase in the brains. DHM suppressed Pb-induced apoptosis, as indicated by the decreased levels of Bax and cleaved caspase-3. DHM also decreased inflammatory cytokines in the brains of Pb-treated mice. DHM decreased amyloid-beta (Aβ) level and nuclear factor-κB nuclear translocation. Moreover, DHM induced the adenosine 5'-monophosphate-activated protein kinase (AMPK) phosphorylation and inhibited the activation of p38, Toll-like receptor 4, myeloid differentiation factor 88, and glycogen synthase kinase-3. Collectively, this is the first report indicating that DHM could improve Pb-induced cognitive functional impairment by preventing oxidative stress, apoptosis, and inflammation and that the protective effect was mediated partly through the AMPK pathway.

Tubeimoside I Protects Dopaminergic Neurons Against Inflammation-Mediated Damage in Lipopolysaccharide (LPS)-Evoked Model of Parkinson's Disease in Rats

Parkinson's disease (PD), a frequent degenerative disease in the elderly, is characterized by dopaminergic neurodegeneration in the substantia nigra pars compacta (SNpc). Neuroinflammation caused by over-activated microglia plays a crucial role in the pathogenesis of PD. Tubeimoside I (TBMS1) has a broad anti-inflammatory effect in peripheral tissues, but the effect on neuroinflammation has not been reported. Therefore, we explored whether TBMS1 could protect dopaminergic neurons by inhibiting the activation of microglia in lipopolysaccharide (LPS)-induced PD rat model. In addition, then, the effect and mechanism of TBMS1 on neuroinflammation were assessed in LPS-exposed murine microglial BV-2 cells. The results in vivo showed that TBMS1 suppressed microglial activation and dopaminergic neurons' reduction in LPS-injected PD rat model. In vitro study found that TBMS1 could inhibit LPS-induced inflammatory responses in BV-2 cells, and this effect was mediated by suppressing the phosphorylation of protein kinase B (AKT), nuclear factor-kappa B (NF-κB p65), p38 and extracellular regulated protein kinases (ERK1/2). Taken together, these results demonstrated for the first time that TBMS1 played a role in protecting dopaminergic neurons by inhibiting neuroinflammation mediated by microglia.

Dehydrodiconiferyl Alcohol Inhibits Osteoclast Differentiation and Ovariectomy-Induced Bone Loss through Acting as an Estrogen Receptor Agonist

Estrogen deficiency after menopause increases bone loss by activating RANKL-induced osteoclast differentiation. Dehydrodiconiferyl alcohol (DHCA), a lignan originally isolated from Cucurbita moschata, has been thought to be a phytoestrogen based on its structure. In this study, we tested whether DHCA could affect RANKL-induced osteoclastogenesis in vitro and ovariectomy-induced bone loss in vivo. In RAW264.7 cells, DHCA inhibited RANKL-induced differentiation of osteoclasts. Consistently, expression of the six osteoclastogenic genes induced by RANKL was down-regulated. DHCA was also shown to suppress the NF-κB and p38 MAPK signaling pathways by activating AMPK. Data from transient transfection assays suggested that DHCA might activate the estrogen receptor signaling pathway. Effects of DHCA on RANKL-induced osteoclastogenesis were reduced when cells were treated with specific siRNA to ERα, but not to ERβ. Interestingly, DHCA was predicted from molecular docking simulation to bind to both ERα and ERβ. Indeed, data from an estrogen receptor competition assay revealed that DHCA acted as an agonist on both estrogen receptors. In the ovariectomized (Ovx) mouse model, DHCA prevented Ovx-induced bone loss by inhibiting osteoclastogenesis. Taken together, our results suggest that DHCA may be developed as an efficient therapeutic for osteoporosis by regulating osteoclastogenesis through its estrogenic effects.

Against NF-κB/thymic stromal lymphopoietin signaling pathway, catechin alleviates the inflammation in allergic rhinitis

BACKGROUND

The prevalence of allergic rhinitis has risen sharply. Previous work has demonstrated the anti-inflammatory effect of catechin, including in models of allergic disease. However, the molecular mechanisms underlying this therapeutic effect remain unclear. Thymic stromal lymphopoietin(TSLP), as a molecule from epithelial cell, has been identified that plays a significant role in the development of allergic disease, and the production of TSLP is related to activation of the NF-κB signaling pathway. For that, we try to research the treatment of catechin for allergic rhinitis and found out possible mechanism under this effect, which was based on TSLP factor.

MATERIALS AND METHODS

Here, the anti-inflammatory effects of catechin were studied in an ovalbumin-induced allergic rhinitis murine model and a vitro experiments using poly(I:C)-stimulated human nasal epithelial cells(HNEpCs). The pharmacological effects of catechin in allergic rhinitis mice were assessed by observing the allergic symptoms, performing hematoxylin and eosin staining and Giemsa staining of the nasal tissues. Additionally, the TSLP expression in epithelial cells was tested by enzyme-linked immunosorbent assays, immunohistochemistry, and western blots. The serum levels of interleukin-5, interleukin-13, and ovalbumin-specific immunoglobulin-E were detected by enzyme-linked immunosorbent assays, and the balance between T helper type 1 and T helper type 2 cells was assessed by flow cytometry. The expression levels of phospho-NF-κBp65, IκBα, and NF-κBp65 proteins were further investigated by western blots or immunofluorescence.

RESULTS

Our results reveal that catechin, in doses of 75, 150, or 300 mg/kg, remitted the allergic symptoms in mice with allergic rhinitis, like sneezing and nasal rubbing. Catechin could reduce the levels of interleukin-5, interleukin-13, and ovalbumin-specific immunoglobulin-E in the serum and restored the T helper type 2/T helper type 1 cell balance and also had anti-thymic stromal lymphopoietin effects. Moreover, as an upstream regulator of TSLP, the NF-κB signal pathway was also suppressed after catechin treatment, which was demonstrated by the observed decrease in phospho-NF-κBp65 and NF-κBp65 levels and the reduction of IκBα degradation and NF-κBp65 nuclear translocation.

CONCLUSIONS

Catechin effectively reduced the inflammation in allergic rhinitis. The underlying mechanism is that catechin inhibited the expression of TSLP in epithelial cells by influencing NF-κB/TSLP pathway.

The Critical Role of IL-10 in the Antineuroinflammatory and Antioxidative Effects of Rheum tanguticum on Activated Microglia

Rheum tanguticum Maxim. ex Balf. (Rt), a traditional Tibetan medicine, is known to exert various bioactivities, including anti-inflammatory and antioxidative activities. The present study was conducted to investigate anti-inflammatory and antioxidative effects of Rt on activated microglia. Rt (10 μg/ml) significantly inhibited the mean protein level of interleukin-1β (IL-1β) in the organotypic hippocampal slice cultures following treatment with chromogranin A (CGA, 10 nM) and pancreastatin (10 nM), endogenous microglial activators present in senile plaques. Rt also significantly inhibited the expression and production of inflammatory and oxidative molecules, including IL-1β, tumor necrosis factor-α, and nitric oxide, by cultured microglia after treatment with CGA. These effects of Rt are considered to be mediated by the secretion of interleukin-10 (IL-10) from microglia, because neutralizing antibodies against IL-10 significantly canceled these effects. To explore the causative components of Rt responsible for inducing the secretion of IL-10, the effects of seven components of Rt on the IL-10 expression in microglia were examined. Among them, aloe-emodin (10 μM) and (+)-catechin (30 μM) were able to induce the secretion of IL-10 from cultured microglia. Therefore, aloe-emodin and (+)-catechin are deemed responsible for the antineuroinflammatory and antioxidative effects of Rt through the secretion of IL-10 from microglia. Accordingly, Rt is considered potentially useful for the treatment of AD.

Inhibitory Effects of Betulinic Acid on LPS-Induced Neuroinflammation Involve M2 Microglial Polarization via CaMKKβ-Dependent AMPK Activation

In response to the microenvironment, microglia may polarize into either an M1 pro-inflammatory phenotype, exacerbating neurotoxicity, or an M2 anti-inflammatory phenotype, conferring neuroprotection. Betulinic acid (BA) is a naturally pentacyclic triterpenoid with considerable anti-inflammatory properties. Here, we aim to investigate the potential effects of BA on microglial phenotype polarization and to reveal the underlying mechanisms of action. First, we confirmed that BA promoted M2 polarization and inhibited M1 polarization in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Then, we demonstrated that the effect of BA on microglial polarization was dependent on AMP-activated protein kinase (AMPK) activation, as evidenced by the fact that both AMPK inhibitor compound C and AMPK siRNA abolished the M2 polarization promoted by BA. Moreover, we found that calmodulin-dependent protein kinase kinase β (CaMKKβ), but not liver kinase B1, was the upstream kinase required for BA-mediated AMPK activation and microglial M2 polarization, via the use of both the CaMKKβ inhibitor STO-609 and CaMKKβ siRNA. Finally, BA enhanced AMPK phosphorylation and promoted M2 microglial polarization in the cerebral cortex of LPS-injected mice brains, which was attenuated by pre-administration of the AMPK inhibitor. This study demonstrated that BA promoted M2 polarization of microglia, thus conferring anti-neuroinflammatory effects via CaMKKβ-dependent AMPK activation.

Effects of quercetin on heart nitric oxide metabolism in l-NAME treated rats

This study investigated the effects of a quercetin-supplemented diet on the biochemical changes installed in the heart of NO-deficient rats in terms of oxidants production and NO bioavailability determinants. Sprague-Dawley rats were subjected to N^ω-nitro-l-arginine methyl ester (l-NAME) treatment (360 mg/L l-NAME in the drinking water, 4 d) with or without supplementation with quercetin (4 g/kg diet). l-NAME administration led to increased blood pressure (BP) (30%), decreased nitric oxide synthase (NOS) activity (50%), and increases in NADPH oxidase (NOX)-dependent superoxide anion production (60%) and p47^phox protein level (65%). The co-administration of quercetin prevented the increase in BP and the activation of NOX but did not modify the decrease in NOS activity caused by l-NAME. In addition, quercetin affected oxidative stress parameters as glutathione oxidation, and the activities of oxidant detoxifying enzymes superoxide dismutase, glutathione peroxidase, and catalase. Thus, quercetin administration counteracts l-NAME effects on NO bioavailability determinants in vivo, essentially through controlling NOX-mediated superoxide anion production.

Petasites japonicus bakkenolide B inhibits lipopolysaccharide‑induced pro‑inflammatory cytokines via AMPK/Nrf2 induction in microglia

Abnormal neuroinflammatory responses have diverse roles in neuronal death, oxidative stress and neurodegenerative diseases, such as Alzheimer's and Parkinson's disease. Microglia regulate these responses via molecular signaling cascades that involve inflammatory cytokines and complement proteins. Bakkenolide B from Petasites japonicus exhibits significant anti‑inflammatory and anti‑allergic bioactivities. The present study investigated the anti‑neuroinflammatory effects and underlying molecular mechanisms of bakkenolide B on the lipopolysaccharide (LPS)‑mediated neuroinflammatory response in microglia. The results indicated that bakkenolide B pretreatment significantly reduced microglial production of interleukin (IL)‑1β, IL‑6, IL‑12, and tumor necrosis factor (TNF)‑α. Furthermore, this effect was associated with reduced production of reactive oxygen species. The role of bakkenolide B was then evaluated in the upregulation of nuclear factor erythroid 2‑related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathways. The results suggested that bakkenolide B significantly upregulated Nrf2/ARE pathway‑related downstream factors, such as NADPH dehydrogenase quinone‑1 (NQO‑1) and heme oxygenase‑1 (HO‑1). Silencing of Nrf2, HO‑1 and NQO‑1 diminished the anti‑neuroinflammatory properties of bakkenolide B. AMP‑activated protein kinase (AMPK) activates the Nrf2/ARE signaling pathway, and the results of the present study demonstrated that bakkenolide B increased AMPK phosphorylation in microglia. In addition, an AMPK inhibitor abolished the bakkenolide B‑induced increase in nuclear Nrf2, NQO‑1 and HO‑1 protein expression. Finally, an AMPK inhibitor diminished the bakkenolide B‑mediated inhibition of LPS‑stimulated TNF‑α production. Taken together, the present results demonstrate that bakkenolide B may be an effective and therapeutically relevant AMPK/Nrf2 pathway activator for suppressing abnormal neuro-inflammation in neurodegenerative diseases.

Baicalein Preventive Treatment Confers Optimal Cardioprotection by PTEN/Akt/NO Activation

Baicalein is a flavonoid with excellent oxidant scavenging capability. It has been reported to protect against a variety of oxidative injuries including ischemia/reperfusion (I/R). However, the optimal treatment strategy for I/R injury and the protective mechanisms are not fully understood. In this study we employed an established chick cardiomyocyte model of I/R and investigated the effects of three baicalein treatment strategies on reactive oxygen species (ROS) scavenging, nitric oxide (NO) production and cell viability. The molecular signaling pathways were also explored. Compared to the I/R control (cell death 52.2[Formula: see text][Formula: see text][Formula: see text]2.0%), baicalein preventive treatment (25[Formula: see text][Formula: see text]M, pretreated for 72[Formula: see text]h and continued through I/R) conferred the best protection (19.5[Formula: see text][Formula: see text][Formula: see text]3.9%, [Formula: see text]), followed by I/R treatment (treated during I/R) and reperfusion treatment (treated at reperfusion only). Preventive and I/R treatments almost completely abolished ROS generation during both ischemic and reperfusion phases, and increased NO production and Akt phosphorylation. Reperfusion treatment reduced the ROS burst in the early reperfusion phase only, and had no effect on NO production and Akt activation. Further, the phosphorylation of phosphatase and tensin homolog (PTEN), a phosphatase negatively regulating Akt activation, was significantly increased by baicalein preventive treatment and slightly by the I/R treatment. PTEN protein expression was reduced in the same trend accordingly. Baicalein reperfusion treatment had no effects on PTEN phosphorylation and expression. Our results indicate that baicalein preventive treatment confers optimal cardioprotection against I/R injury, and this protection involves effective oxidant scavenging and the activation of PTEN/Akt/NO pathway.

AMPK activation: Role in the signaling pathways of neuroinflammation and neurodegeneration

Adenosine monophosphate-activated protein kinase (AMPK) is an evolutionarily conserved sensor of cellular energy status and has been reported to be involved in chronic inflammatory disorders. AMPK is expressed in immune cells, such as dendritic cells, macrophages, lymphocytes and neutrophils, and is an important regulator of inflammatory responses through the regulation of complex signaling networks in part by inhibiting downstream cascade pathways, such as nuclear factor kB, which is a key regulator of innate immunity and inflammation, as well as acting as a negative regulator of toll-like receptors. Recent data suggest that AMPK dysregulation may participate in neurodegenerative diseases, such as multiple sclerosis, Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and neuropathies. However, there are conflicting reports on the benefits or detrimental effects of AMPK in distinct pathological conditions. This paper offers a review of the recent literature on the pharmacological modulation of the AMPK system as a potential molecular target in the management of neurodegenerative diseases.

Polyphenols Beyond Barriers: A Glimpse into the Brain

BACKGROUND

Ageing can be simply defined as the process of becoming older, which is genetically determined but also environmentally modulated. With the continuous increase of life expectancy, quality of life during ageing has become one of the biggest challenges of developed countries. The quest for a healthy ageing has led to the extensive study of plant polyphenols with the aim to prevent age-associated deterioration and diseases, including neurodegenerative diseases. The world of polyphenols has fascinated researchers over the past decades, and in vitro, cell-based, animal and human studies have attempted to unravel the mechanisms behind dietary polyphenols neuroprotection.

METHODS

In this review, we compiled some of the extensive and ever-growing research in the field, highlighting some of the most recent trends in the area.

RESULTS

The main findings regarding polypolyphenols neuroprotective potential performed using in vitro, cellular and animal studies, as well as human trials are covered in this review. Concepts like bioavailability, polyphenols biotransformation, transport of dietary polyphenols across barriers, including the blood-brain barrier, are here explored.

CONCLUSION

The diversity and holistic properties of polypolyphenol present them as an attractive alternative for the treatment of multifactorial diseases, where a multitude of cellular pathways are disrupted. The underlying mechanisms of polypolyphenols for nutrition or therapeutic applications must be further consolidated, however there is strong evidence of their beneficial impact on brain function during ageing. Nevertheless, only the tip of the iceberg of nutritional and pharmacological potential of dietary polyphenols is hitherto understood and further research needs to be done to fill the gaps in pursuing a healthy ageing.

Anti-Inflammatory Effect of Ethanolic Extract of Sargassum serratifolium in Lipopolysaccharide-Stimulated BV2 Microglial Cells

Sargassum serratifolium was found to contain high concentrations of meroterpenoids, having strong antioxidant, anti-inflammatory, and neuroprotective activities. This study aims to investigate the anti-inflammatory mechanisms of an ethanolic extract of S. serratifolium (ESS) using lipopolysaccharide (LPS)-stimulated BV2 microglial cells and to identify the anti-inflammatory components in ESS. The level of proinflammatory cytokines was measured by enzyme-linked immunosorbent assay. The expression of inflammation-related proteins and mRNA was evaluated by Western blot and reverse transcription-polymerase chain reaction analysis, respectively. Anti-inflammatory activities of isolated components from ESS were analyzed in LPS-stimulated BV2 cells. ESS inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 and the expression of inducible NO synthase and cyclooxygenase-2. ESS also decreased the release of proinflammatory cytokines in a dose-dependent manner. LPS-induced nuclear factor-kappa B (κB) transcriptional activity and translocation into the nucleus were remarkably suppressed by ESS through the prevention of inhibitor κB-α degradation. The main anti-inflammatory components in ESS were identified as sargahydroquinoic acid, sargachromenol, and sargaquinoic acid based on the inhibition of NO production using LPS-stimulated BV2 cells. Furthermore, treatment with ESS significantly reduced levels of tumor necrosis factor-α and interleukin-1β stimulated with LPS in mouse hippocampus. Our results indicate that ESS can be used as a functional food or therapeutic agent for the treatment of neuroinflammatory diseases.

Anti-inflammatory, free radical scavenging and alpha-glucosidase inhibitory activities of Hamelia patens and its chemical constituents

Context Hamelia patens Jacq. (Rubiaceae) is traditionally used to treat wounds, inflammation and diabetes. However, there is still a lack of scientific evidence to support these applications. Objective The objective of this study is to evaluate the anti-inflammatory, antioxidant and antidiabetic activities of Hamelia patens, and identify its bioactive compounds. Materials and methods Four extracts were obtained by maceration and liquid-liquid extraction: HEX, DCM-EtOAc, MeOH-EtOAc and MeOH-Aq. The anti-inflammatory effect was evaluated orally on rat paw carrageenan-induced oedema over 6 h (50, 200 and 500 mg/kg), and topically in mouse ear oedema induced by 12-tetradecanoylphorbol-13-acetate (TPA) after 4 h (0.5 and 1 mg/ear). We also evaluated myeloperoxidase levels in ear tissue, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and in vitro α-glucosidase inhibition. The chemical compounds were separated by column chromatography and identified by spectroscopic analysis. Results We found that the oral administration of the HEX extract at 500 and 200 mg/kg significantly decreased the carrageenan-induced inflammation after 1 and 3 h, respectively. The MeOH-EtOAc extract significantly inhibited myeloperoxidase activity (83.5%), followed by the DCM-EtOAc extract (76%), β-sitosterol/stigmasterol (72.7%) and the HEX extract (55%), which significantly decreased oedema induced by TPA at both doses, giving a similar effect to indomethacin. We also found that the MeOH-EtOAc, MeOH-Aq and DCM-EtOAc extracts showed good DPPH scavenging activity (IC50 values of 18.6, 93.9 and 158.2 μg/mL, respectively). The HEX extract showed the lowest α-glucosidase inhibition (an IC50 value of 26.07 μg/mL), followed by the MeOH-EtOAc extract (an IC50 value of 30.18 μg/mL), β-sitosterol/stigmasterol (IC50 34.6 μg/mL) and compound A ((6E,10E,14E,18E)-2,6,10,14,18,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, an IC50 value of 114.6 μg/mL), which were isolated for the first time from Hamelia patens. Discussion and conclusion Hamelia patens possesses anti-inflammatory, antioxidant and α-glucosidase inhibitory activities, which support its traditional use. These effects can be attributed to the identified compounds.

Dietary phytochemicals and neuro-inflammaging: from mechanistic insights to translational challenges

An extensive literature describes the positive impact of dietary phytochemicals on overall health and longevity. Dietary phytochemicals include a large group of non-nutrients compounds from a wide range of plant-derived foods and chemical classes. Over the last decade, remarkable progress has been made to realize that oxidative and nitrosative stress (O&NS) and chronic, low-grade inflammation are major risk factors underlying brain aging. Accumulated data strongly suggest that phytochemicals from fruits, vegetables, herbs, and spices may exert relevant negative immunoregulatory, and/or anti-O&NS activities in the context of brain aging. Despite the translational gap between basic and clinical research, the current understanding of the molecular interactions between phytochemicals and immune-inflammatory and O&NS (IO&NS) pathways could help in designing effective nutritional strategies to delay brain aging and improve cognitive function. This review attempts to summarise recent evidence indicating that specific phytochemicals may act as positive modulators of IO&NS pathways by attenuating pro-inflammatory pathways associated with the age-related redox imbalance that occurs in brain aging. We will also discuss the need to initiate long-term nutrition intervention studies in healthy subjects. Hence, we will highlight crucial aspects that require further study to determine effective physiological concentrations and explore the real impact of dietary phytochemicals in preserving brain health before the onset of symptoms leading to cognitive decline and inflammatory neurodegeneration.