AMPK activation attenuates central sensitization in a recurrent nitroglycerin-induced chronic migraine mouse model by promoting microglial M2-type polarization.

BACKGROUND: Energy metabolism disorders and neurogenic inflammation play important roles in the central sensitization to chronic migraine (CM). AMP-activated protein kinase (AMPK) is an intracellular energy sensor, and its activation regulates inflammation and reduces neuropathic pain. However, studies on the involvement of AMPK in the regulation of CM are currently lacking. Therefore, this study aimed to explore the mechanism underlying the involvement of AMPK in the central sensitization to CM. METHODS: Mice with recurrent nitroglycerin (NTG)-induced CM were used to detect the expression of AMPK protein in the trigeminal nucleus caudalis (TNC). Following intraperitoneal injection of the AMPK activator 5-aminoimidazole-4-carboxyamide ribonucleoside (AICAR) and inhibitor compound C, the mechanical pain threshold, activity level, and pain-like behaviors in the mice were measured. The expression of calcitonin gene-related peptide (CGRP) and cytokines, M1/M2 microglia, and NF-κB pathway activation were detected after the intervention. RESULTS: Repeated NTG injections resulted in a gradual decrease in AMPK protein expression, and the negative regulation of AMPK by increased ubiquitin-like plant homeodomain and RING finger domain 1 (UHRF1) expression may counteract AMPK activation by increasing ADP/ATP. AICAR can reduce the hyperalgesia and pain-like behaviors of CM mice, improve the activity of mice, reduce the expression of CGRP, IL-1ß, IL-6, and TNF-α in the TNC region, and increase the expression of IL-4 and IL-10. Moreover, AMPK in TNC was mainly located in microglia. AICAR could reduce the expression of inducible NO synthase (iNOS) in M1 microglia and increase the expression of Arginase 1 (Arg1) in M2 microglia by inhibiting the activation of NF-κB pathway. CONCLUSIONS: AMPK was involved in the central sensitization of CM, and the activation of AMPK reduced neuroinflammation in NTG-induced CM mice. AMPK may provide new insights into interventions for energy metabolism disorders and neurogenic inflammation in migraine.

Therapeutic effect of notoginseng saponins before and after fermentation on blood deficiency rats.

Notoginseng saponins (NS) are the active ingredients in Panax notoginseng (Burk.) F.H. Chen (PN). NS can be transformed depending on how the extract is processed. Fermentation has been shown to produce secondary ginsenosides with increased bioavailability. However, the therapeutic effect of fermented NS (FNS) requires further study. The present study compared the compositions and activities of FNS and NS in blood deficiency rats, which resembles the symptoms of anemia in modern medicine, induced by acetylphenylhydrazine and cyclophosphamide. A total of 32 rats were randomly divided into control, model, FNS and NS groups. A blood deficiency model was established and then treatment was orally administered for 21 days. The results of component analysis indicated that some saponins transformed during the fermentation process resulting in a decrease of notoginsenoside R1, and ginsenosides Rg1, Rb1 and Re, and an increase in ginsenosides Rd, Rh2, compound K, protopanaxadiol and protopanaxatriol. The animal results showed that both FNS and NS increased the number of white blood cells (WBCs), red blood cells, hemoglobin, platelets and reticulocytes, and the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), erythropoietin (EPO) and thrombopoietin (TPO), decreased the G0/G1 phase and increased G2/M phase, and decreased the apoptosis rate of bone marrow (BM) cells, which suggested a contribution to the recovery of hematopoietic function of the BM cells. FNS and NS increased the protein expression levels of the cytokines IL-4, IL-10, IL-12, IL-13, TGF-ß, IL-6, IFN-γ and TNF-α, and the mRNA expression levels of transcription factors GATA binding protein 3 and T-box expressed in T cell (T-bet). FNS and NS treatment also increased the number of CD4+ T cells, and decreased the enlargement of the rat spleen and thymus atrophy, which indicated a protective effect on the organs of the immune system. The results of the present study demonstrated that compared with NS, FNS showed an improved ability to increase the levels of WBCs, lymphocytes, GM-CSF, EPO, TPO, aspartate aminotransferase, IL-10, IL-12, IL-13 and TNF-α, and the mRNA expression levels of T-bet, and decrease alanine aminotransferase levels. The differences seen for FNS treatment could arise from their improved bioavailability compared with NS, due to the larger proportion of hydrophobic ginsenosides produced during fermentation.

METTL3 regulates TFRC ubiquitination and ferroptosis through stabilizing NEDD4L mRNA to impact stroke.

BACKGROUND: Stroke is a major medical problem, and novel therapeutic targets are urgently needed. This study investigates the protective role and potential mechanisms of the N6-methyladenosine (m6A) RNA methyltransferase METTL3 against cerebral injury resulting from insufficient cerebral blood flow. METHODS: In this study, we constructed mouse MCAO models and HT-22 cell OGD/R models to mimic ischemic stroke-induced brain injury and neuronal damage. We generated NEDD4L knockout and METTL3 overexpression models and validated therapeutic effects using infarct volume, brain edema, and neurologic scoring. We performed qRT-PCR, western blotting, and co-immunoprecipitation to assess the influence of NEDD4L on ferroptosis markers and TFRC expression. We verified the effect of NEDD4L on TFRC ubiquitination by detecting half-life and ubiquitination. Finally, we validated the impact of METTL3 on NEDD4L mRNA stability and MCAO outcomes in both in vitro and in vivo experimental models. RESULT: We find NEDD4L expression is downregulated in MCAO models. Overexpressing METTL3 inhibits the iron carrier protein TFRC by upregulating the E3 ubiquitin ligase NEDD4L, thereby alleviating oxidative damage and ferroptosis to protect the brain from ischemic injury. Mechanistic studies show METTL3 can methylate and stabilize NEDD4L mRNA, enhancing NEDD4L expression. As a downstream effector, NEDD4L ubiquitinates and degrades TFRC, reducing iron accumulation and neuronal ferroptosis. CONCLUSION: In summary, we uncover the METTL3-NEDD4L-TFRC axis is critical for inhibiting post-ischemic brain injury. Enhancing this pathway may serve as an effective strategy for stroke therapy. This study lays the theoretical foundation for developing m6A-related therapies against ischemic brain damage.

Relationship between individual differences in pain empathy and task- and resting-state EEG.

Pain empathy is a complex form of psychological inference that enables us to understand how others feel in the context of pain. Since pain empathy may be grounded in our own pain experiences, it exhibits huge inter-individual variability. However, the neural mechanisms behind the individual differences in pain empathy and its association with pain perception are still poorly understood. In this study, we aimed to characterize brain mechanisms associated with individual differences in pain empathy in adult participants (n = 24). The 32-channel electroencephalography (EEG) was recorded at rest and during a pain empathy task, and participants viewed static visual stimuli of the limbs submitted to painful and nonpainful stimulation to solicit empathy. The pain sensitivity of each participant was measured using a series of direct current stimulations. In our results, the N2 of Fz and the LPP of P3 and P4 were affected by painful pictures. We found that both delta and alpha bands in the frontal and parietal cortex were involved in the regulation of pain empathy. For the delta band, a close relationship was found between average power, either in the resting or task state, and individual differences in pain empathy. It suggested that the spectral power in Fz's delta band may reflect subjective pain empathy across individuals. For the alpha band, the functional connectivity between Fz and P3 under painful picture stimulation was correlated to individuals' pain sensitivity. It indicated that the alpha band may reflect individual differences in pain sensitivity and be involved in pain empathy processing. Our results suggested the distinct role of the delta and alpha bands of EEG signals in pain empathy processing and may deepen our understanding of the neural mechanisms underpinning pain empathy.

Effect of central corneal curvature on corneal material stiffness parameter acquired by dynamic corneal responses.

The stress-strain index (SSI) is a measure of corneal material stiffness, which is obtained using the Corvis ST algorithm based on dynamic corneal response parameters. The reduced SSI corresponds to the longer axial length (AL). In a previous study, we found SSI increases as the corneal curvature flattens, whereas a flatter corneal curvature indicates a longer AL (emmetropia or myopia). Therefore, in this cross-sectional study, we aimed to address these contradictory findings. First, we characterized the features of SSI, curvature radius of the anterior corneal surface (CR), and AL and analyzed their correlation with advanced myopia. Next, we compared the relationship between AL and SSI after adjusting for the effect of CR. We found a significant positive correlation between SSI and CR, which contradicts the developmental law of axial myopia. Furthermore, after accounting for the effect of CR, we observed a stronger correlation between SSI and AL than that in the unadjusted model. In conclusion, CR is an independent influencing factor for SSI in addition to AL, which masked the decrease in SSI caused by prolonged AL in axial myopia.

Fiber liquid-pressure sensor with high sensitivity and a wide measurement range using photopolymer.

This paper presents a novel fiber liquid-pressure sensor that uses photopolymer glue to generate Fabry-Perot (F-P) interference, resulting in high sensitivity and a wide measurement range. The sensor comprises a single-mode fiber and photopolymer glue; the latter adheres to the fiber's end face and is decomposed by a 405-nm laser to create an air channel with a diameter of 5.9 µm and a length of 50 µm. When the air channel is placed underwater, a 17.5-µm air cavity forms between the fiber core and the air-liquid boundary due to the pressure balance, creating an F-P interferometer. Based on experimental results, the sensor has an average pressure sensitivity of 5.68 nm/kPa over 0.49-2.94 kPa. The sensitivity can be maintained at this level across different pressure measurement ranges (up to about 500 kPa) by using a 980-nm laser's radiation pressure to reset the air-liquid boundary. Besides its high sensitivity and wide measurement range, the sensor's straightforward structure, durability, affordability, compactness, and simple construction make it an appealing choice for liquid pressure measurement applications in various fields.

Effect of corneal stiffness decrease on axial length elongation in myopia determined based on a mathematical estimation model.

Purpose: To investigate the relationship between the corneal material stiffness parameter stress-strain index (SSI) and axial length (AL) elongation with varying severities of myopia, based on a mathematical estimation model. Methods: This single-center, cross-sectional study included data from healthy subjects and patients preparing for refractive surgery in the Qingdao Eye Hospital of Shandong First Medical University. Data were collected from July 2021 to April 2022. First, we performed and tested an estimated AL model ( A L M o r g a n ) based on the mathematical equation proposed by Morgan. Second, we proposed an axial increment model ( Δ A L ) corresponding to spherical equivalent error (SER) based on A L e m m e t r o p i a ( A L M o r g a n at SER = 0) and subject's real AL. Finally, we evaluated the variations of Δ A L with SSI changes based on the mathematical estimation model. Results: We found that AL was closely associated with A L M o r g a n (r = 0.91, t = 33.8, p < 0.001) with good consistency and SER was negatively associated with Δ A L (r = -0.89, t = -30.7, p < 0.001). The association of SSI with AL, A L e m m e t r o p i a , and Δ A L can be summarized using the following equations: A L = 27.7 - 2.04 × S S I , A L e m m e t r o p i a = 23.2 + 0.561 × S S I , and Δ A L = 4.52 - 2.6 × S S I . In adjusted models, SSI was negatively associated with AL (Model 1: ß = -2.01, p < 0.001) and Δ A L (Model 3: ß = -2.49, p < 0.001) but positively associated with A L e m m e t r o p i a (Model 2: ß = 0.48, p < 0.05). In addition, SSI was negatively associated with Δ A L among subjects with AL ≥ 26 mm (ß = -1.36, p = 0.02). Conclusion: AL increased with decreasing SSI in myopia.

Analysis of m6A modulator-mediated methylation modification patterns and the tumor microenvironment in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the most common histological subtype of lung cancer. In the development and progression of LUAD, epigenetic aberration plays a crucial role. However, the function of RNA N6-methyladenosine (m6A) modifications in the LUAD progression is unknown. The m6A regulator modification patterns in 955 LUAD samples were analyzed comprehensively. Patterns were systematically correlated with the tumor microenvironment (TME) cell-infiltration characteristics. Using principal component analysis algorithms, the m6Ascore was generated to quantify m6A modification patterns in individual tumors. Then, their values for predicting prognoses and therapeutic response in LUAD patients were assessed. Three distinct m6A modification patterns in LUAD were identified. Among them, the prognosis of m6Acluster C was the best, while the prognosis of m6Acluster A was the worst. Interestingly, the characterization of TME cell infiltration and biological behavior differed among the three patterns. To evaluate m6A modification patterns within individual tumors, an m6Ascore signature was constructed. The results showed that the high m6Ascore group was associated with a better prognosis; tumor somatic mutations and tumor microenvironment differed significantly between the high- and low- m6Ascore groups. Furthermore, in the cohort with anti-CTLA-4 treatment alone, patients with a high m6Ascore had higher ICI scores, which indicated significant therapeutic advantage and clinical benefits.

Hemostatic Effect of 20(S)-Panaxadiol by Induced Platelet Aggregation Depending on Calcium Signaling Pathway.

Panax notoginseng (Burk.) F.H. Chen is the most traditional hemostatic herb in China. Our previous research found that 20(S)-protopanaxadiol showed the hemostatic effect. And 20(S)-panaxadiol (PD) has a similar structure to 20(S)-protopanaxadiol with a dammarane skeleton. So, this article mainly studies the hemostatic effect of PD. The mouse tail amputation and liver scratch models were used to detect the hemostatic effect of PD. Blood routine and plasma coagulation parameters were measured by using a blood analyzer. The platelet aggregometer analyzed the platelet aggregation rate and adenosine triphosphate (ATP) concentration. Moreover, the intracellular calcium concentration ([Ca2+] i ), P-selectin (CD62P), PAC-1 (GP IIb/IIIa receptor marker), and cyclic adenosine monophosphate (cAMP) of platelets were also detected. The results showed that PD obviously shortened the bleeding time of the model mouse, affected the RBC and PLT parameters of rats, reduced APTT and TT, elevated FIB concentration, and promoted human/rat-washed platelet aggregation in vitro. PD promoted the release of ATP and [Ca2+] i and slightly increased the expression of CD62P and PAC-1 of platelets without 1 mM Ca2+. After adding 1 mM Ca2+, PD obviously increased ATP releasing and CD62P and GP IIb/IIIa expression rate and decreased the cAMP level of platelets. These parameter changes of PD-caused platelet were inhibited by vorapaxar. Besides, PD increased the phosphorylation of phosphoinositide 3-kinase/protein kinase B/glycogen synthase kinase 3ß (PI3K/Akt/GSK3ß) of human platelets. PD is an important hemostatic ingredient in Panax notoginseng, which induced platelet aggregation by affecting the calcium signaling and activating the PI3K/Akt/GSK3ß signaling pathway.

Nomogram Prediction for Postoperative Mortality of Orthotopic Liver Transplantation.

OBJECTIVES: The purpose of this study was to assess and predict risk factors for death within 30 days after orthotopic liver transplant and to develop a nomogram to predict mortality after liver transplant. MATERIALS AND METHODS: We retrospectively studied 185 patients who underwent orthotopic livertransplant at Sichuan Provincial People's Hospital from January 1, 2010, to December 31, 2018. Multivariable logistic regression analyses were used to identify independent risk factors. A nomogram model was developed to predict mortality after liver transplant. The performance of the prediction model was assessed and validated by receiver operating characteristic curve and bootstrap methods (1000 replications). RESULTS: Multivariable logistic regression analyses revealed that tracheal extubation time, postoperative infection, and intraperitoneal hemorrhage posttransplant were independentrisk factors for mortality after liver transplant. The receiver operating characteristic curve of the nomogram prediction model was 0.896 (96% CI, 0.803-0.989), and the mean absolute error of internal validation by bootstrap (1000 replications) was 0.019 (n = 184). These results showed that the nomogram model had an excellent prediction accuracy. CONCLUSIONS: A nomogram model can provide clinicians with an individualized risk assessment of perioperative mortality in liver transplant recipients.

Manual Removal versus Spontaneous Delivery of the Placenta at Cesarean Section: A Meta-Analysis of Randomized Controlled Trials.

PURPOSE: Several randomized clinical trials (RCTs) investigated the effects of the manual placental removal on hemorrhage or other hemorrhage-related complications compared with the spontaneous placental removal during cesarean section (CS), while the results remained controversial and were inconsistent. The purpose of this meta-analysis was to quantify the pooled effects of the methods of placental removal on hemorrhage during CS. PATIENTS AND METHODS: A systematic literature search was conducted using PubMed, EMBASE, Web of Science, and Google Scholar. Heterogeneity was tested by I 2 statistics and Q-statistic. The random-effects model or fixed-effects model were used to calculate the pooled effect for the included studies according to heterogeneity. And the term of standardized mean difference (SMD) with 95% confidence intervals (CI) was pooled and estimated the effects across all studies. RESULTS: A total of nine RCTs were included in this meta-analysis. Compared with spontaneous group, manual placental removal increased the amount of hemorrhage (SMD = 0.53, 95% CI [0.12, 0.94]; Z = 2.54, P = 0.011) and increased the risk of endometritis (OR = 1.84, 95% CI [1.31, 2.58]; Z = 3.52, P < 0.0001). In contrast, there was no significant difference concerning the operating time (SMD = -0.30, 95% CI [-0.85, 0.24]; Z = 1.09, P = 0.276), the length of hospital stays (SMD = 0.11, 95% CI [-0.08, 0.30]; Z = 1.11, P = 0.265), and blood transfusion requirement (OR = 1.36, 95% CI [0.91, 2.04]; Z = 1.52, P = 0.129), respectively. CONCLUSION: Comparing with spontaneous placental removal, manual placental removal appeared to be less positive effect during CS. Because of the limitations of this meta-analysis, more high-quality RCTs are needed to confirm our findings.

FBXO10 prevents chronic unpredictable stress-induced behavioral despair and cognitive impairment through promoting RAGE degradation.

AIMS: Depression is one of the leading causes of disability worldwide. The receptor for advanced glycosylation end products (RAGE) is closely related to chronic stress and is a target of F-box protein O10 (FBXO10) which promotes the degradation of RAGE by ubiquitination. Here, we explored the role of FBXO10 and RAGE in chronic unpredictable stress (CUS)-induced behavioral despair, cognitive impairment, neuroinflammation, and the polarization microglia. METHODS: Male C57BL/6 mice with or without infusion of viral in the medial prefrontal cortex (PFC) were subjected to CUS. Then the mice were exposed to forced swim test, sucrose consumption test, novelty-suppressed feeding test, and temporal object recognition task to assess the behavioral despair and cognitive impairment. Inflammatory cytokines and the neurotrophic factor brain-derived neurotrophic factor (BDNF) levels in PFC were assessed by enzyme-linked immunosorbent assay. Immunofluorescence and immunohistochemistry staining were performed to observe the activation and phenotypic transformation of microglia in PFC. LPS-induced cell model was constructed to explore the effect of FBXO10/RAGE axis in the polarization of microglia in vitro. RESULTS: FBXO10 promoted RAGE degradation by ubiquitination in BV2 cells. FBXO10 protein levels were reduced whereas RAGE protein levels were enhanced in CUS mice. FBXO10 overexpression or RAGE knockdown inhibited proinflammatory cytokine release, promoted BDNF expression, mitigated the depressive-like and cognitive impairment behaviors, and affected the polarization of microglia induced by CUS exposure. FBXO10/RAGE axis promoted the polarization of microglia from the M1 to the M2 phenotype in vitro. Moreover, p38 MAPK and NF-κΒ were identified to be the downstream effect factors for FBXO10/RAGE axis. CONCLUSIONS: FBXO10 administration prevents CUS-induced behavioral despair, cognitive impairment, neuroinflammation, and the polarization of microglia through decreasing the accumulation of RAGE, p38 MAPK, and NF-κΒ, suggesting potential therapeutic strategies for the prevention and treatment of depression.

A randomised trial: effects of different anesthesia methods on early perioperative pain sensitivity and cellular immune function in patients undergoing radical mastectomy.

BACKGROUND: This study sought to investigate the effects of transversus thoracic muscle plane-pectoral nerves (TTP-PECS) block combined with propofol anesthesia on early perioperative pain sensitivity and cellular immune function in patients undergoing radical mastectomy. METHODS: A total of 115 patients who underwent radical mastectomy for breast cancer at our hospital from January 2019 to January 2021 were selected as the study subjects. The patients were allocated to the control group (n=57) or observation group (n=58) using a random number method. The control group was given simple general anesthesia, and the observation group was given TTP-PECS block combined with propofol anesthesia. The recovery time, pain [visual analogue scoring (VAS)] scores, and incidences of adverse reactions were compared between the 2 groups. Hemodynamic indicators [i.e., heart rate (HR), mean arterial pressure (MAP)], stress indicators [i.e., blood glucose (GLU), epinephrine (E), cortisol (Cor)], and the cellular immune function ofthe2 groups before anesthesia (T0), at the end of operation (T1), 1day after operation (T2) and 3days after operation (T3) were recorded. RESULTS: The spontaneous respiration recovery time, time to full wakefulness and the extubation time of the observation group were shorter than those of the control group (P<0.05). The observation group had lower VAS scores than the control group at 2, 8, 12, and 24 h after operation (P<0.05). The levels of MAP, HR, GLU, E and Cor in the observation group at T1, T2, and T3 were lower than those in the control group (P<0.05). Compared to the control group, the observation group had increased cluster of differentiation (CD)3+, CD4+, and CD4+/CD8+ cells (P<0.05), but there were no significant differences in CD8+ and natural killer (NK) cells between the 2 groups (P>0.05). The incidence of adverse reactions in the observation group was lower than that in the control group (8.62% vs. 24.56%) (P<0.05). CONCLUSIONS: TTP-PECS block combined with propofol anesthesia can relieve pain, shorten the recovery time, stabilize the hemodynamic level, and alleviate the stress responses of patients undergoing radical mastectomy with a slight suppression of cellular immune function and high safety. TRIAL REGISTRATION: Chinese Clinical Trial Registration Center ChiCTR2100048438.