Microglia-derived TNF-α contributes to RVLM neuronal mitochondrial dysfunction via blocking the AMPK-Sirt3 pathway in stress-induced hypertension

Different expression of circulating microRNA profile in tibetan OSAHS with metabolic syndrome patients

Recent empirical investigations reinforce the understanding of a profound interconnection between metabolic functions and Obstructive Sleep Apnea-hypopnea Syndrome (OSAHS). This study identifies distinctive miRNA signatures in OSAHS with Metabolic Syndrome (Mets) patients from healthy subjects, that could serve as diagnostic biomarkers or describe differential molecular mechanisms with potential therapeutic implications. In this study, OSAHS with MetS patients showed significantly higher Apnea Hyponea Index(AHI), but lower oxygen desaturation index(ODI 4/h) and minimum pulse oxygen saturation(SpO2). A total of 33 differentially expressed miRNAs by Limma method, and 31 differentially expressed miRNAs by DEseq2 method were screened. In addition, GO enrichment analysis of target genes associated with differentially expressed miRNAs revealed significant enrichment in metabolic processes, suggesting that the differential expression of OSAHS-induced miRNAs may contribute to the progression of metabolic disorders through the regulation of metabolic pathways. Furthermore, KEGG pathway enrichment analysis revealed significant enrichment in the p53 signaling pathway and several other pathways. Notably, the Wnt signaling pathway, PI3K-Akt signaling pathway, cAMP signaling pathway, and AMPK signaling pathway are implicated in the metabolic processes of glucose dysregulation and lipid homeostasis, as well as the pathogenesis of hypertension associated with OSAHS. We identified IKBKB, PIK3R1, and MAP2K1 as the target genes most associated with Mets pathogenesis in OSAHS, regulated by miR-503-5p, miR-497-5p, and miR-497-5p, respectively. Additionally, the target genes of differentially expressed miRNAs between Tibetan OSAHS patients with MetS and healthy individuals are regulated by transcription factors such as NR2C1, STAT3, STAT5a, HIF1a, ETV4, NANOG, RELA, SP1, E2F1, NFKB1, AR, and MYC. In conlusion, we found differentially expressed miRNAs in Tibetan OSAHS patients with Metabolic Syndrome for the first time. Enrichment analysis results suggest that differentially expressed miRNAs may involved in the development of OSAHS-related metabolic disorders by regulating metabolic pathways. We also revealed that IKBKB, PIK3R1, and MAP2K1 are mostly associated with metabolic disorder in OSAHS, and miR-503-5p and miR-497-5p may regulate the development of MetS associated with OSAHS by modulating IKBKB, PIK3R1, and MAP2K1.

Airborne Staphylococcus aureus Exposure Induces Depression-like Behaviors in Mice via Abnormal Neural Oscillation and Mitochondrial Dysfunction

Airborne Staphylococcus aureus exists widely in the natural environment and is closely related to human health. Growing evidence indicates that environmental air pollution elevates the risk of depressive disorders. However, the potential role of airborne S. aureus in the development of depression remains unclear. This study aims to elucidate the neurotoxic effects and potential mechanisms associated with depression caused by airborne S. aureus. Mice were randomly divided into four groups, and the experimental groups with environmental S. aureus were at 4.89 × 102, 8.89 × 105, and 1.27 × 108 CFU/m3 during four consecutive weeks. Airborne S. aureus exposure contributed to depression-like behaviors in mice, especially in the high-concentration group. The electroencephalography signal analysis identified uncoupling of theta and gamma bands and a shift of the beta rhythm toward delta oscillation in the medial prefrontal cortex of mice. Neuropathological analysis showed uplifted neuroinflammation and elevated levels of oxidative stress in the brain. Neuroinflammation and oxidative stress resulted in mitochondrial dysfunction, which could lead to apoptosis. Together, this study provides a strong basis for understanding the adverse outcomes of airborne S. aureus on mental health disorders.

Understanding Headaches Attributed to Cranial and/or Cervical Vascular Disorders: Insights and Challenges for Neurologists

In recent decades, cranial and cervical vascular disorders have become major global health concerns, significantly impacting patients, families, and societies. Headache is a prevalent symptom of these vascular diseases and can often be the initial, primary, or sole manifestation. The intricate relationship between headaches and cranial/cervical vascular disorders poses a diagnostic and therapeutic challenge, with the underlying mechanisms remaining largely elusive. Understanding this association is crucial for the early diagnosis, prevention, and intervention of such conditions. This review aims to provide a comprehensive overview of the clinical features and potential pathogenesis of headaches attributed to cranial and cervical vascular disorders and provide a reference for disease management and a basis for potential pathological mechanisms.

Hippocampal cannabinoid type 2 receptor alleviates chronic neuropathic pain-induced cognitive impairment via microglial DUSP6 pathway in rats

Approximately 50% of patients with chronic neuropathic pain experience cognitive impairment, which negatively impacts their quality of life. The cannabinoid type 2 receptor (CB2R) may be involved in hippocampal cognitive processes. However, its role in chronic neuropathic pain-induced cognitive impairment remains elusive. Spared nerve injury (SNI) was used to induce chronic neuropathic pain in rats, while the novel-object recognition test and the Y-maze test were employed to assess cognitive function. Immunofluorescence, western blotting, and stereotaxic hippocampal microinjection were utilized to elucidate the potential mechanisms. We observed a reduction in mechanical pain threshold and cognitive impairment in SNI rats. This was accompanied by a tendency for hippocampal microglia to adopt pro-inflammatory functions. Notably, no changes were detected in CB2R expression. However, downregulation of the endogenous ligands AEA and 2-AG was evident. Hippocampal microinjection of a CB2R agonist mitigated cognitive impairment in SNI rats, which correlated with a tendency for microglia to adopt anti-inflammatory functions. Additionally, SNI-induced activation of the p-ERK/NFκB pathway in the hippocampus. Activation of CB2R reversed this process by upregulating DUSP6 expression in microglia. The effects elicited by CB2R activation could be inhibited through the downregulation of microglial DUSP6 via hippocampal adeno-associated virus (AAV) microinjection. Conversely, overexpression of hippocampal DUSP6 using AAV ameliorated the cognitive deficits observed in SNI rats, which remained unaffected by the administration of a CB2R antagonist. Our findings demonstrate that activation of hippocampal CB2R can mitigate chronic neuropathic pain-induced cognitive impairment through the modulation of the DUSP6/ERK/NFκB pathway.

BMP10 accelerated spinal astrocytic activation in neuropathic pain via ALK2/smad1/5/8 signaling

Background

Astrocytic activation in the spinal dorsal horn contributes to the central sensitization of neuropathic pain. Bone morphogenetic protein (BMP) 10, one of the BMPs highly expressed in the central nervous system, has been demonstrated to have an accelerated effect on astrocytic activation. This study aimed to investigate the functional effects of BMP10 on the activation of astrocytes in the spinal dorsal horn of animal model of neuropathic pain and to explore potential mechanisms involved in this process.

Methods

A neuropathic pain mice model was established using the spared nerve injury (SNI). Western blot analysis was performed to detect the expressional levels of BMP10, activin receptor-like receptor 2 (ALK2), Smad1/5/8, phosphorylated Smad1/5/8, and glial fibrillary acidic protein (GFAP). Immunofluorescence staining was used to detect BMP10, ALK2, and GFAP distribution and expression. The behavioral changes in mice were evaluated using paw withdrawal threshold (PWT), thermal withdrawal latency (TWL), and open field test (OFT). The BMP10 siRNA, Smad1 siRNA, BMP10 peptide, and ALK2-IN-2 (ALK2 inhibitor) were intrathecally administrated to mice. A model of lipopolysaccharide (LPS)-stimulated astrocytes was established to investigate the effect of Smad1. The transfection efficiency of siRNAs was detected by western blot and qRT-PCR analysis.

Results

BMP10 levels were increased in the L4-6 ipsilateral spinal dorsal horn of SNI mice and particularly elevated in astrocytes. Consistently, GFAP and phosphorylated Smad1/5/8 were upregulated in the L4-6 ipsilateral spinal dorsal horn after SNI, indicating the activation of astrocytes and Smad1/5/8 signaling. An intrathecal injection of BMP10 siRNA abrogated pain hypersensitivity and astrocytic activation in SNI mice. In addition, intrathecal administration of BMP10 peptide evoked pain hypersensitivity and astrocytic activation in normal mice, and this action was reversed by inhibiting the ALK2. Furthermore, targeting Smad1 in vitro with the help of siRNA inhibited the activation of astrocytes induced by LPS. Finally, targeting Smad1 abrogated BMP10-induced hypersensitivity and activation of astrocytes.

Conclusion

These findings indicate that the BMP10/ALK2/Smad1/5/8 axis plays a key role in pain hypersensitivity after peripheral nerve injury, which indicates its stimulative ability toward astrocytes.

Application of neutrophil to lymphocyte ratio in ankylosing spondylitis: Based on bibliometric and visualization analysis

Ankylosing spondylitis (AS) as a autoimmune disease involves inflammatory responses in the development of the disease, often causing changes in the neutrophil to lymphocyte ratio (NLR). In the past few decades, research on the relationship between NLR and AS has generally shown an upward trend. This study adopts the bibliometrics method to analyze the development trend, frontier, and hotspots of global research in this field in the past 2 decades. By searching for publications in the SCI-Expanded edition of the Web of Science Core Collection, the information of literature published between 2000 and 2023 is recorded. Based on the VOSviewer, CiteSpace and Excel, bibliometric analysis, and visualization analysis are conducted on the overall distribution of annual output, leading countries, active institutions, journals, authors, co-cited references, and keywords. Through retrieving and screening, a total of 1654 papers are obtained for analysis. In the past 2 decades, the number of publications related to this field has shown an increasing trend. The United States has the highest Hirsch index (H-index) and publication volume. The most productive institution is Harvard University, while the H-index of the University of Milan in Italy is far ahead. Frontiers in Immunology is the institution with the highest output. The H-index of the Annals of the Rheumatic holds the top position. This study has uncovered the main emphasis on NLR in AS research and has provided clarification regarding the value of NLR as a biomarker for immune inflammatory response in the diagnosis and prognosis of AS.

Indole-3 acetic acid induced cardiac hypertrophy in Wistar albino rats

Indole-3-acetic acid (IAA) is the most widely utilized plant growth regulator. Despite its extensive usage, IAA is often overlooked as an environmental pollutant. Due to its protein-binding nature, it also functions as a uremic toxin, contributing to its association with chronic kidney disease (CKD). While in vitro and epidemiological research have demonstrated this association, the precise impact of IAA on cardiovascular disease in animal models is unknown. The main objective of this study is to conduct a mechanistic analysis of the cardiotoxic effects caused by IAA using male Wistar albino rats as the experimental model. Three different concentrations of IAA (125, 250, 500 mg/kg) were administered for 28 days. The circulating IAA concentration mimicked previously observed levels in CKD patients. The administration of IAA led to a notable augmentation in heart size and heart-to-body weight ratio, indicating cardiac hypertrophy. Echocardiographic assessments supported these observations, revealing myocardial thickening. Biochemical and gene expression analyses further corroborated the cardiotoxic effects of IAA. Dyslipidemia, increased serum c-Troponin-I levels, decreased SOD and CAT levels, and elevated lipid peroxidation in cardiac tissue were identified. Moreover, increased expression of cardiac inflammatory biomarkers, including ANP, BNP, β-MHC, Col-III, TNF-α, and NF-κB, was also found in the IAA-treated animals. Histopathological analysis confirmed the cardiotoxic nature of IAA, providing additional evidence of its adverse effects on cardiovascular health. These results offer insights into the potential negative impact of IAA on cardiovascular function, and elucidating the underlying mechanisms of its cardiotoxicity.

Axonal protection by combination of ripasudil and brimonidine with upregulation of p-AMPK in TNF-induced optic nerve degeneration

PURPOSE

The ROCK inhibitor ripasudil hydrochloride hydrate was shown to have axonal protective effects in TNF-induced optic nerve degeneration. The α2-adrenoreceptor agonist brimonidine was also shown to exert axonal protection. The current study aimed to elucidate whether additive axonal protection was achieved by the simultaneous injection of ripasudil and brimonidine and examine the association with AMPK activation.

METHODS

Intravitreal administration was performed in the following groups: PBS, TNF, or TNF with ripasudil, with brimonidine, or with a combination of ripasudil and brimonidine. Axon numbers were counted to evaluate the effects against axon loss. Immunoblot analysis was performed to examine phosphorylated AMPK expression in optic nerves, and immunohistochemical analysis was performed to evaluate the expression levels of p-AMPK and neurofilament in the optic nerve.

RESULTS

Both ripasudil alone or brimonidine alone resulted in significant neuroprotection against TNF-induced axon loss. The combination of ripasudil and brimonidine showed additive protective effects. Combined ripasudil and brimonidine plus TNF significantly upregulated p-AMPK levels in the optic nerve compared with the TNF groups. Immunohistochemical analysis revealed that p-AMPK is present in axons and enhanced by combination therapy.

CONCLUSION

The combination of ripasudil and brimonidine may have additive protective effects compared with single-agent treatment alone. These protective effects may be at least partially associated with AMPK activation.