Neuroprotection of Triptolide against Amyloid-Beta1-42-induced toxicity via the Akt/mTOR/p70S6K-mediated Autophagy Pathway

Bushenhuoluo Decoction improves polycystic ovary syndrome by regulating exosomal miR-30a-5p/ SOCS3/mTOR/NLRP3 signaling-mediated autophagy and pyroptosis

BACKGROUND

Polycystic ovary syndrome (PCOS) is a frequent and complicated endocrine disease that remains a major reason for infertility. Bushenhuoluo Decotion (BSHLD) has been validated to exhibit curative effects on PCOS. This study was aimed to explore the potential mechanism underlying the therapeutic action of BSHLD.

METHODS

PCOS rat model was induced by dehydroepiandrosterone (DHEA). Serum hormone and cytokines levels and ovarian pathological alterations were measured to assess ovarian function. Exosomes (Exos) were identified by Transmission electron microscopy and Nanoparticle Tracking Analysis. RT-qPCR, Western blotting, immunohistochemical staining, and immunofluorescence staining were performed to detect molecule expressions. Proliferation and pyroptosis of granulosa cells (GCs) were evaluated by CCK-8 and flow cytometry, respectively. The binding relationship between miR-30a-5p and suppressor of cytokine signaling 3 (SOCS3) was verified by dual luciferase reporter and RIP assays.

RESULTS

BSHLD treatment improved serum hormone abnormality, insulin sensitivity, and ovarian morphologic changes of PCOS rats. Moreover, BSHLD treatment restrained the excessive autophagy and pyroptosis in ovarian tissues of PCOS rats. Moreover, BSHLD reduced the expression of miR-30a-5p in serum, serum-derived Exos, and ovarian tissues, thus inhibiting autophagy and NLRP3-mediated pyroptosis in GCs. Mechanistically, SOCS3 was proved as a target of miR-30a-5p and could activate mTOR/P70S6K pathway to repress autophagy. The inhibitory effect of miR-30a-5p deficiency on autophagy and pyroptosis of GCs was attenuated by rapamycin.

CONCLUSION

Collectively, BSHLD suppressed autophagy and pyroptosis to improve POCS by regulating exosomal miR-30a-5p/SOCS3/mTOR signaling.

Triptolide activates the Nrf2 signaling pathway and inhibits the NF-κB signaling pathway to improve Alzheimer disease

Alzheimer disease (AD) is a common neurodegenerative disease with pathological features of accumulated amyloid plaques, neurofibrillary tangles, and the significant inflammatory environment. These features modify the living microenvironment for nerve cells, causing the damage, dysfunction, and death. Progressive neuronal loss directly leads to cognitive decline in AD patients and is closely related to brain inflammation. Therefore, impairing inflammation via signaling pathways may facilitate either the prevention or delay of the degenerative process. Triptolide has been evidenced to possess potent anti-inflammatory effect. In this review, we elaborate on two signaling pathways (the NF-κB and Nrf2 signaling pathways) that are involved in the anti-inflammatory effect of triptolide.

The impact of aging and oxidative stress in metabolic and nervous system disorders: programmed cell death and molecular signal transduction crosstalk

Life expectancy is increasing throughout the world and coincides with a rise in non-communicable diseases (NCDs), especially for metabolic disease that includes diabetes mellitus (DM) and neurodegenerative disorders. The debilitating effects of metabolic disorders influence the entire body and significantly affect the nervous system impacting greater than one billion people with disability in the peripheral nervous system as well as with cognitive loss, now the seventh leading cause of death worldwide. Metabolic disorders, such as DM, and neurologic disease remain a significant challenge for the treatment and care of individuals since present therapies may limit symptoms but do not halt overall disease progression. These clinical challenges to address the interplay between metabolic and neurodegenerative disorders warrant innovative strategies that can focus upon the underlying mechanisms of aging-related disorders, oxidative stress, cell senescence, and cell death. Programmed cell death pathways that involve autophagy, apoptosis, ferroptosis, and pyroptosis can play a critical role in metabolic and neurodegenerative disorders and oversee processes that include insulin resistance, β-cell function, mitochondrial integrity, reactive oxygen species release, and inflammatory cell activation. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), AMP activated protein kinase (AMPK), and Wnt1 inducible signaling pathway protein 1 (WISP1) are novel targets that can oversee programmed cell death pathways tied to β-nicotinamide adenine dinucleotide (NAD+), nicotinamide, apolipoprotein E (APOE), severe acute respiratory syndrome (SARS-CoV-2) exposure with coronavirus disease 2019 (COVID-19), and trophic factors, such as erythropoietin (EPO). The pathways of programmed cell death, SIRT1, AMPK, and WISP1 offer exciting prospects for maintaining metabolic homeostasis and nervous system function that can be compromised during aging-related disorders and lead to cognitive impairment, but these pathways have dual roles in determining the ultimate fate of cells and organ systems that warrant thoughtful insight into complex autofeedback mechanisms.

Cognitive Impairment in Multiple Sclerosis

Almost three million individuals suffer from multiple sclerosis (MS) throughout the world, a demyelinating disease in the nervous system with increased prevalence over the last five decades, and is now being recognized as one significant etiology of cognitive loss and dementia. Presently, disease modifying therapies can limit the rate of relapse and potentially reduce brain volume loss in patients with MS, but unfortunately cannot prevent disease progression or the onset of cognitive disability. Innovative strategies are therefore required to address areas of inflammation, immune cell activation, and cell survival that involve novel pathways of programmed cell death, mammalian forkhead transcription factors (FoxOs), the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), and associated pathways with the apolipoprotein E (APOE-ε4) gene and severe acute respiratory syndrome coronavirus (SARS-CoV-2). These pathways are intertwined at multiple levels and can involve metabolic oversight with cellular metabolism dependent upon nicotinamide adenine dinucleotide (NAD+). Insight into the mechanisms of these pathways can provide new avenues of discovery for the therapeutic treatment of dementia and loss in cognition that occurs during MS.

Amyloid β-based therapy for Alzheimer's disease: challenges, successes and future

Amyloid β protein (Aβ) is the main component of neuritic plaques in Alzheimer's disease (AD), and its accumulation has been considered as the molecular driver of Alzheimer's pathogenesis and progression. Aβ has been the prime target for the development of AD therapy. However, the repeated failures of Aβ-targeted clinical trials have cast considerable doubt on the amyloid cascade hypothesis and whether the development of Alzheimer's drug has followed the correct course. However, the recent successes of Aβ targeted trials have assuaged those doubts. In this review, we discussed the evolution of the amyloid cascade hypothesis over the last 30 years and summarized its application in Alzheimer's diagnosis and modification. In particular, we extensively discussed the pitfalls, promises and important unanswered questions regarding the current anti-Aβ therapy, as well as strategies for further study and development of more feasible Aβ-targeted approaches in the optimization of AD prevention and treatment.

Cellular Metabolism: A Fundamental Component of Degeneration in the Nervous System

It is estimated that, at minimum, 500 million individuals suffer from cellular metabolic dysfunction, such as diabetes mellitus (DM), throughout the world. Even more concerning is the knowledge that metabolic disease is intimately tied to neurodegenerative disorders, affecting both the central and peripheral nervous systems as well as leading to dementia, the seventh leading cause of death. New and innovative therapeutic strategies that address cellular metabolism, apoptosis, autophagy, and pyroptosis, the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), growth factor signaling with erythropoietin (EPO), and risk factors such as the apolipoprotein E (APOE-ε4) gene and coronavirus disease 2019 (COVID-19) can offer valuable insights for the clinical care and treatment of neurodegenerative disorders impacted by cellular metabolic disease. Critical insight into and modulation of these complex pathways are required since mTOR signaling pathways, such as AMPK activation, can improve memory retention in Alzheimer's disease (AD) and DM, promote healthy aging, facilitate clearance of β-amyloid (Aß) and tau in the brain, and control inflammation, but also may lead to cognitive loss and long-COVID syndrome through mechanisms that can include oxidative stress, mitochondrial dysfunction, cytokine release, and APOE-ε4 if pathways such as autophagy and other mechanisms of programmed cell death are left unchecked.