Anti-Inflammatory and Neuroprotective Effects of Morin in an MPTP-Induced Parkinson’s Disease Model

Bioactive components in prunella vulgaris for treating Hashimoto's disease via regulation of innate immune response in human thyrocytes

Background

Hashimoto's thyroiditis (HT) is a thyroid autoimmune disease characterized by lymphocytic infiltration and thyroid destruction. Prunella vulgaris (PV) is a traditional Chinese herbal medicine with documented clinical efficacy in treating HT. We previously reported an immunoregulatory effect of PV in thyrocytes; however, the bioactive components of PV remained unclear. This study aimed to elucidate key components of PV for treating HT and their acting mechanisms.

Methods

Network pharmacology was used to predict key PV components for HT. The predicted components were tested to determine whether they could exert an immunoregulatory effect of PV in human thyrocytes. Limited proteolysis-mass spectrometry (Lip-MS) was used to explore interacting proteins with PV components in human thyrocytes. Microscale thermophoresis binding assay was used to evaluate the affinity of PV components with the target protein.

Results

Eleven PV components with 192 component targets and 3415 HT-related genes were gathered from public databases. With network pharmacology, a 'component-target-disease' network was established wherein four flavonoids including quercetin, luteolin, kaempferol, morin, and a phytosterol, β-sitosterol were predicted as key components in PV for HT. In stimulated primary human thyrocytes or Nthy-ori-31 cells, key components inhibited gene expressions of inflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interferon-β (IFN-β), cellular apoptosis, and activation of nuclear factor κB (NF-κB) and interferon regulatory factor 3 (IRF-3). Heat shock protein 90 alpha, class A, member 1 (HSP90AA1), was identified to interact with flavonoids in PV by Lip-MS. Morin had the highest affinity with HSP90AA1 (KD = 122.74 μM), followed by kaempferol (KD = 168.53 μM), luteolin (KD = 293.94 μM), and quercetin (KD = 356.86 μM).

Conclusion

Quercetin, luteolin, kaempferol, morin, and β-sitosterol reproduced an anti-inflammatory and anti-apoptosis effect of PV in stimulated human thyrocytes, which potentially contributed to the treatment efficacy of PV in HT.

Experimental Parkinson models and green chemistry approach

Parkinson's is the most common neurodegenerative disease after Alzheimer's. Motor findings in Parkinson's occur as a result of the degeneration of dopaminergic neurons starting in the substantia nigra pars compacta and ending in the putamen and caudate nucleus. Loss of neurons and the formation of inclusions called Lewy bodies in existing neurons are characteristic histopathological findings of Parkinson's. The disease primarily impairs the functional capacity of the person with cardinal findings such as tremor, bradykinesia, etc., as a result of the loss of dopaminergic neurons in the substantia nigra. Experimental animal models of Parkinson's have been used extensively in recent years to investigate the pathology of this disease. These models are generally based on systemic or local(intracerebral) administration of neurotoxins, which can replicate many features of Parkinson's mammals. The development of transgenic models in recent years has allowed us to learn more about the modeling of Parkinson's. Applying animal modeling, which shows the most human-like effects in studies, is extremely important. It has been demonstrated that oxidative stress increases in many neurodegenerative diseases such as Parkinson's and various age-related degenerative diseases in humans and that neurons are sensitive to it. In cases where oxidative stress increases and antioxidant systems are inadequate, natural molecules such as flavonoids and polyphenols can be used as a new antioxidant treatment to reduce neuronal reactive oxygen species and improve the neurodegenerative process. Therefore, in this article, we examined experimental animal modeling in Parkinson's disease and the effect of green chemistry approaches on Parkinson's disease.

Alcohol-exacerbates post-traumatic stress psychiatric behavior and its neuropathological sequalae in experimental mice: preventive effects of morin

Posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) are very prevalent and co-occurring. It is unclear how alcohol exacerbates PTSD predicaments owing to less characterized pathophysiological mechanisms. Also, studies on pharmacological agents that can effectively reverse PTSD-AUD comorbidity have, to date, been scarce. Hence, we designed a methodological approach to investigate the pathophysiological mechanisms and pharmacological outcomes of morin, a neuroprotective flavonoid in mice. After 7 days of PTSD following single-prolonged stress (SPS) induction in mice, the PTSD mice were exposed to intermittent binge ethanol administration using ethanol (2g/kg, oral gavage) every other day, alongside daily morin (50 and 100mg/kg) or fluoxetine (10mg/kg) from days 8-21. The consequences of PTSD-AUD behavior, hypothalamic-pituitary-adrenal-axis (HPA-axis) dysfunction, neurochemistry, oxidative/nitrergic stress, and inflammation were evaluated in the prefrontal-cortex (PFC), striatum, and hippocampus of mice. The exacerbated anxiety-like behavior, and spatial/non-spatial memory deficits, with general depressive phenotypes and social stress susceptibility by SPS-ethanol interaction, were alleviated by morin and fluoxetine, evidenced by reduced corticosterone release and adrenal hypertrophy. SPS-ethanol exacerbates dopamine, serotonin, and glutamic acid decarboxylase alterations, and monoamine oxidase-B and acetylcholinesterase hyperactivities in the striatum, PFC, and hippocampus, respectively, which were prevented by morin. Compared to SPS-ethanol aggravation, morin prevented TNF-α, and IL-6 release, malondialdehyde and nitrite levels, with improved antioxidant (glutathione, superoxide-dismutase, catalase) levels in the hippocampus, PFC, and striatum. Overall, these findings suggest that AUD exacerbated PTSD might be primarily connected, among other mechanisms, with aggravated HPA-axis dysfunction, upregulated neurochemical degradative enzymes, enhancement of oxidative/nitrergic stress and neuroinflammation, stereo-selectively in the mice brains, which morin abated via the preventive mechanisms.

Intranasal Administration of Umbilical Cord Mesenchymal Stem Cell Exosomes Alleviates Parkinson's Disease

Parkinson's disease (PD) is a common and complex neurodegenerative disease. This disease is typically characterized by the formation of Lewy bodies in multiple brain regions and dopaminergic neuronal loss in the substantia nigra pars compacta, resulting in non-motor symptoms (e.g., olfactory deficits) and motor dysfunction in the late stages. There is yet no effective cure for Parkinson's disease. Considering the neuroprotective effects of exosomes, we investigated whether intranasal administration of umbilical cord mesenchymal stem cell exosomes could improve behavioral functions in PD mice. First, exosomes were endocytosed by the cells in vitro and in vivo, indicating that exosomes can cross the blood-brain barrier. Second, we found that both motor and non-motor functions of the PD models were effectively improved during intranasal exosomes treatment. Finally, the activity of olfactory bulb neurons was improved and the loss of dopaminergic neurons in the substantia nigra pars compacta was reversed. Moreover, exosomes attenuated microglia and astrocyte activation, leading to a low level of inflammation in the brain. In conclusion, our study provided a new reference for the clinical application of exosomes in the treatment of PD.

Effectiveness of Flavonoid-Rich Diet in Alleviating Symptoms of Neurodegenerative Diseases

Over the past decades, there has been a significant increase in the burden of neurological diseases, including neurodegenerative disorders, on a global scale. This is linked to a widespread demographic trend in which developed societies are aging, leading to an increased proportion of elderly individuals and, concurrently, an increase in the number of those afflicted, posing one of the main public health challenges for the coming decades. The complex pathomechanisms of neurodegenerative diseases and resulting varied symptoms, which differ depending on the disease, environment, and lifestyle of the patients, make searching for therapies for this group of disorders a formidable challenge. Currently, most neurodegenerative diseases are considered incurable. An important aspect in the fight against and prevention of neurodegenerative diseases may be broadly understood lifestyle choices, and more specifically, what we will focus on in this review, a diet. One proposal that may help in the fight against the spread of neurodegenerative diseases is a diet rich in flavonoids. Flavonoids are compounds widely found in products considered healthy, such as fruits, vegetables, and herbs. Many studies indicated not only the neuroprotective effects of these compounds but also their ability to reverse changes occurring during the progression of diseases such as Alzheimer's, Parkinson's and amyotrophic lateral sclerosis. Here, we present the main groups of flavonoids, discussing their characteristics and mechanisms of action. The most widely described mechanisms point to neuroprotective functions due to strong antioxidant and anti-inflammatory effects, accompanied with their ability to penetrate the blood-brain barrier, as well as the ability to inhibit the formation of protein aggregates. The latter feature, together with promoting removal of the aggregates is especially important in neurodegenerative diseases. We discuss a therapeutic potential of selected flavonoids in the fight against neurodegenerative diseases, based on in vitro studies, and their impact when included in the diet of animals (laboratory research) and humans (population studies). Thus, this review summarizes flavonoids' actions and impacts on neurodegenerative diseases. Therapeutic use of these compounds in the future is potentially possible but depends on overcoming key challenges such as low bioavailability, determining the therapeutic dose, and defining what a flavonoid-rich diet is and determining its potential negative effects. This review also suggests further research directions to address these challenges.

Characteristics of anticancer activity of CBP/p300 inhibitors - Features of their classes, intracellular targets and future perspectives of their application in cancer treatment

Due to the contribution of highly homologous acetyltransferases CBP and p300 to transcription elevation of oncogenes and other cancer promoting factors, these enzymes emerge as possible epigenetic targets of anticancer therapy. Extensive efforts in search for small molecule inhibitors led to development of compounds targeting histone acetyltransferase catalytic domain or chromatin-interacting bromodomain of CBP/p300, as well as dual BET and CBP/p300 inhibitors. The promising anticancer efficacy in in vitro and mice models led CCS1477 and NEO2734 to clinical trials. However, none of the described inhibitors is perfectly specific to CBP/p300 since they share similarity of a key functional domains with other enzymes, which are critically associated with cancer progression and their antagonists demonstrate remarkable clinical efficacy in cancer therapy. Therefore, we revise the possible and clinically relevant off-targets of CBP/p300 inhibitors that can be blocked simultaneously with CBP/p300 thereby improving the anticancer potential of CBP/p300 inhibitors and pharmacokinetic predicting data such as absorption, distribution, metabolism, excretion (ADME) and toxicity.

Aptamers for the Delivery of Plant-Based Compounds: A Review

Natural compounds have a high potential for the treatment of various conditions, including infections, inflammatory diseases, and cancer. However, they usually present poor pharmacokinetics, low specificity, and even toxicity, which limits their use. Therefore, targeted drug delivery systems, typically composed of a carrier and a targeting ligand, can enhance natural product selectivity and effectiveness. Notably, aptamers-short RNA or single-stranded DNA molecules-have gained attention as promising ligands in targeted drug delivery since they are simple to synthesize and modify, and they present high tissue permeability, stability, and a wide array of available targets. The combination of natural products, namely plant-based compounds, with a drug delivery system utilizing aptamers as targeting agents represents an emerging strategy that has the potential to broaden its applications. This review discusses the potential of aptamers as targeting agents in the delivery of natural compounds, as well as new trends and developments in their utilization in the field of medicine.

Total Glucosides of White Paeony Capsule ameliorates Parkinson's disease-like behavior in MPTP-induced mice model by regulating LRRK2/alpha-synuclein signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The Total Glucosides of White Paeony Capsule (TGPC), one of the traditional Chinese patent medicines, has been used for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) in clinical practice. Besides, the components of TGPC are extracted from Radix Paeoniae Alba (RPA) and have displayed neuroprotective properties.

AIM OF THE STUDY

The present study was designed to evaluate the anti-PD-like effects of TGPC on a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mice model and explore its potential molecular mechanisms.

MATERIALS AND METHODS

Behavioral tests, hematoxylin and eosin (HE) staining, Nissl staining, immunohistochemistry (IHC), western blotting (WB) and Enzyme-Linked Immunosorbent Assay (ELISA) were performed in this study.

RESULTS

It was observed that TGPC treatment (150, 300 mg/kg) significantly reversed MPTPinduced PD-like behaviors, such as reduced locomotive activity in the open field test, prolonged time to turn downward on the ball (T-turn) and to climb down the whole pole (T-descend) in the pole test, decreased movement scores in the traction test and extended the latency to fall in the hanging wire test. In addition, TGPC improved neurodegeneration, inhibited the excessive activation of microglia and suppressed the overproduction of proinflammatory cytokines induced by MPTP, partially by restoring leucine-rich repeat kinase 2 (LRRK2) activity and inhibiting alpha-synuclein (α-syn) mediated neuroinflammation signaling.

CONCLUSION

Taken together, TGPC exhibited neuroprotective effects on MPTP-induced mice model of PD, which was associated with the prevention of neuroinflammation and neurodegeneration modulated by LRRK2/α-syn pathway.

Amelioration of Astrocyte-Mediated Neuroinflammation by EI-16004 Confers Neuroprotection in an MPTP-induced Parkinson's Disease Model

Parkinson's disease (PD) is a neurodegenerative disorder that results in motor impairment due to dopaminergic neuronal loss. The pathology of PD is closely associated with neuroinflammation, which can be characterized by astrocyte activation. Thus, targeting the inflammatory response in astrocytes might provide a novel therapeutic approach. We conducted a luciferase assay on an in-house chemical library to identify compounds with anti-inflammatory effects capable of reducing MPP+-induced NF-κB activity in astrocytes. Among the compounds identified, EI-16004, a novel 3-benzyl-N-phenyl-1H-pyrazole-5-carboxamides, exhibited a significant anti-inflammatory effect by significantly reducing MPP+-induced astrocyte activation. Biochemical analysis and docking simulation indicated that EI-16004 inhibited the MPP+-induced phosphorylation of p65 by attenuating ERK phosphorylation, and EI-16004 reduced pro-inflammatory cytokine and chemokine levels in astrocytes. In vivo studies on the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model in male C57BL/6 mice showed that EI-16004 ameliorated motor impairment and protected against dopaminergic neuronal loss, and EI-16004 effectively mitigated the MPTP-induced astrocyte activation in striatum (STR) and substantia nigra (SN). These results indicate EI-16004 is a potential neuroprotective agent for the prevention and treatment of astrocyte-mediated neuroinflammatory conditions in PD.

Therapeutic targeting of Ras/Raf/MAPK pathway by natural products: A systematic and mechanistic approach for neurodegeneration

BACKGROUND

Multiple dysregulated pathways are behind the pathogenesis of neurodegenerative diseases (NDDs); however, the crucial targets are still unknown. Oxidative stress, apoptosis, autophagy, and inflammation are the most dominant pathways that strongly influence neurodegeneration. In this way, targeting the Ras/Raf/mitogen-activated protein kinases (MAPKs) pathway appears to be a developing strategy for combating NDDs like Parkinson's disease, Alzheimer's disease, stroke, aging, and other NDDs. Accordingly, plant secondary metabolites have shown promising potentials for the simultaneous modulation of the Ras/Raf/MAPKs pathway and play an essential role in NDDs. MAPKs include p38 MAPK, extracellular signal-regulated kinase 1/2 (ERK 1/2), and c-Jun N-terminal kinase (JNK), which are important molecular players in neurodegeneration. Ras/Raf, which is located the upstream of MAPK pathway influences the initiation and progression of neurodegeneration and is regulated by natural products.

PURPOSE

Thus, the present study aimed to investigate the neuroprotective roles of plant- and marine-derived secondary metabolites against several NDDs through the modulation of the Ras/Raf/MAPK signaling pathway.

STUDY DESIGN AND METHODS

A systematic and comprehensive review was performed to highlight the modulatory roles of natural products on the Ras/Raf/MAPK signaling pathway in NDDs, according to the PRISMA guideline, using scholarly electronic databases, including PubMed, Scopus, and Web of Sciences. Associated reference lists were also searched for the literature review.

RESULTS

From a total of 1495 results, finally 107 articles were included in the present study. The results show that several natural compounds such as alkaloid, phenolic, terpenoids, and nanoformulation were shown to have modulatory effects on the Ras/Raf/MAPKs pathway.

CONCLUSION

Natural products are promising multi-targeted agents with on NDDs through Ras/Raf/MAPKs pathway. Nevertheless, additional and complementary studies are necessary to check its efficacy and potential side effects.

Regulatory Roles of Flavonoids in Caspase-11 Non-Canonical Inflammasome-Mediated Inflammatory Responses and Diseases

Inflammasomes are multiprotein complexes that activate inflammatory responses by inducing pyroptosis and secretion of pro-inflammatory cytokines. Along with many previous studies on inflammatory responses and diseases induced by canonical inflammasomes, an increasing number of studies have demonstrated that non-canonical inflammasomes, such as mouse caspase-11 and human caspase-4 inflammasomes, are emerging key players in inflammatory responses and various diseases. Flavonoids are natural bioactive compounds found in plants, fruits, vegetables, and teas and have pharmacological properties in a wide range of human diseases. Many studies have successfully demonstrated that flavonoids play an anti-inflammatory role and ameliorate many inflammatory diseases by inhibiting canonical inflammasomes. Others have demonstrated the anti-inflammatory roles of flavonoids in inflammatory responses and various diseases, with a new mechanism by which flavonoids inhibit non-canonical inflammasomes. This review discusses recent studies that have investigated the anti-inflammatory roles and pharmacological properties of flavonoids in inflammatory responses and diseases induced by non-canonical inflammasomes and further provides insight into developing flavonoid-based therapeutics as potential nutraceuticals against human inflammatory diseases.