Mitoapocynin Attenuates Organic Dust Exposure-Induced Neuroinflammation and Sensory-Motor Deficits in a Mouse Model

Decoding mechanisms and protein markers in lung-brain axis

BACKGROUND

The lung-brain axis represents a complex bidirectional communication network that is pivotal in the crosstalk between respiratory and neurological functions. This review summarizes the current understanding of the mechanisms and protein markers that mediate the effects of lung diseases on brain health.

MAIN FINDINGS

In this review, we explore the mechanisms linking lung injury to neurocognitive impairments, focusing on neural pathways, immune regulation and inflammatory responses, microorganism pathways, and hypoxemia. Specifically, we highlight the role of the vagus nerve in modulating the central nervous system response to pulmonary stimuli; Additionally, the regulatory function of the immune system is underscored, with evidence suggesting that lung-derived immune mediators can traverse the blood-brain barrier, induce neuroinflammation and cognitive decline; Furthermore, we discuss the potential of lung microbiota to influence brain diseases through microbial translocation and immune activation; Finally, the impact of hypoxemia is examined, with findings indicating that it can exacerbate cerebral injury via oxidative stress and impaired perfusion. Moreover, we analyze how pulmonary conditions, such as pneumonia, ALI/ARDS, and asthma, contribute to neurological dysfunction. Prolonged mechanical ventilation can also contribute to cognitive impairment. Conversely, brain diseases (e.g., stroke, traumatic brain injury) can lead to acute respiratory complications. In addition, protein markers such as TLR4, ACE2, A-SAA, HMGB1, and TREM2 are crucial to the lung-brain axis and correlate with disease severity. We also discuss emerging therapeutic strategies targeting this axis, including immunomodulation and microbiome engineering. Overall, understanding the lung-brain interplay is crucial for developing integrated treatment strategies and improving patient outcomes. Further research is needed to elucidate the molecular mechanisms and foster interdisciplinary collaboration.

Life-threatening risk factors contribute to the development of diseases with the highest mortality through the induction of regulated necrotic cell death

Chronic diseases affecting the cardiovascular system, diabetes mellitus, neurodegenerative diseases, and various other organ-specific conditions, involve different underlying pathological processes. However, they share common risk factors that contribute to the development and progression of these diseases, including air pollution, hypertension, obesity, high cholesterol levels, smoking and alcoholism. In this review, we aim to explore the connection between four types of diseases with different etiologies and various risk factors. We highlight that the presence of risk factors induces regulated necrotic cell death, leading to the release of damage-associated molecular patterns (DAMPs), ultimately resulting in sterile inflammation. Therefore, DAMP-mediated inflammation may be the link explaining how risk factors can lead to the development and maintenance of chronic diseases. To explore these processes, we summarize the main cell death pathways activated by the most common life-threatening risk factors, the types of released DAMPs and how these events are associated with the pathophysiology of diseases with the highest mortality. Various risk factors, such as smoking, air pollution, alcoholism, hypertension, obesity, and high cholesterol levels induce regulated necrosis. Subsequently, the release of DAMPs leads to chronic inflammation, which increases the risk of many diseases, including those with the highest mortality rates.

Neuroinflammaging: A Tight Line Between Normal Aging and Age-Related Neurodegenerative Disorders

Aging in the healthy brain is characterized by a low-grade, chronic, and sterile inflammatory process known as neuroinflammaging. This condition, mainly consisting in an up-regulation of the inflammatory response at the brain level, contributes to the pathogenesis of age-related neurodegenerative disorders. Development of this proinflammatory state involves the interaction between genetic and environmental factors, able to induce age-related epigenetic modifications. Indeed, the exposure to environmental compounds, drugs, and infections, can contribute to epigenetic modifications of DNA methylome, histone fold proteins, and nucleosome positioning, leading to epigenetic modulation of neuroinflammatory responses. Furthermore, some epigenetic modifiers, which combine and interact during the life course, can contribute to modeling of epigenome dynamics to sustain, or dampen the neuroinflammatory phenotype. The aim of this review is to summarize current knowledge about neuroinflammaging with a particular focus on epigenetic mechanisms underlying the onset and progression of neuroinflammatory cascades in the central nervous system; furthermore, we describe some diagnostic biomarkers that may contribute to increase diagnostic accuracy and help tailor therapeutic strategies in patients with neurodegenerative diseases.

Fluoxetine protects against inflammation and promotes autophagy in mice model of post-traumatic stress disorder

Post-traumatic stress disorder is a major public health problem due to its frequency, chronicity, and disability that impact daily life. Studies have evidenced that the activation/inhibition of autophagy and excessive activation of microglia have a relationship with PTSD. For this purpose, C57BL/6 mice were employed to establish the post-traumatic stress disorder pathology mice model by conditioned fear and single prolonged stress (CF + SPS). Fluoxetine and PLX3397 were administered. PTSD-like behaviors were alleviated following fluoxetine treatment, evidenced via open field and conditioned fear test. Autophagy-associated proteins were upregulated, and inflammation factors were reduced after fluoxetine treatment. Microglia depletion mice showed a lower inflammatory level. In conclusion, fluoxetine can promote autophagy and inhibit neuroinflammation in mice model of PTSD, providing a theoretical basis for fluoxetine in treating PTSD.