Temporin-GHaR Peptide Alleviates LPS-Induced Cognitive Impairment and Microglial Activation by Modulating Endoplasmic Reticulum Stress.

Neuroinflammation is considered an important factor that leads to cognitive impairment. Microglia play a crucial role in neuroinflammation, which leads to cognitive impairment. This study aimed at determining whether temporin-GHaR peptide (GHaR) could improve cognitive function and at uncovering the underlying mechanisms. We found that GHaR treatment alleviated LPS-induced cognitive impairment and inhibited activation of microglia in LPS-induced mice. Furthermore, GHaR inhibited activation of endoplasmic reticulum stress (ERS) and the NF-κB signaling pathway in LPS-induced mice. In vitro, GHaR inhibited M1 polarization of BV2 cells and suppressed TNF-α and IL-6 secretion. Additionally, GHaR neuronal cell viability and apoptosis were induced by LPS-activated microglia-conditioned medium. Moreover, in LPS-induced BV2 cells, GHaR inhibited activation of ERS and the NF-κB signaling pathway. In summary, GHaR improved LPS-induced cognitive and attenuated inflammatory responses via microglial activation reversal. In conclusion, the neuroprotective effects of GHaR were mediated via the ERS signaling pathway.

The clinical significance of circulating glucose-regulated protein 78, Caspase-3, and C/EBP homologous protein levels in patients with heart failure.

Background and aims: The destruction of endoplasmic reticulum (ER) homeostasis leads to heart failure (HF), which further aggravates ER stress. Limited data are available on the levels of ER stress markers in HF patients in clinical practice. This study aimed to determine the clinical significance of the ER stress markers, glucose-regulated protein 78 (GRP78), Caspase-3, and C/EBP homologous protein (CHOP), in predicting HF and its severity. Materials and methods: A total of 62 patients with HF and 44 healthy controls were enrolled in the study, and all participants were followed-up for 2 years. Results: Serum GRP78, Caspase-3, and CHOP levels were significantly higher in patients with HF than those in healthy controls. The level of GRP78 increased with the severity of HF. GRP78 levels were negatively correlated with left ventricular ejection fraction, and positively correlated with N-terminal B-type natriuretic peptide, D-dimer, and lactic acid. Serum GRP78 and Caspase-3 levels showed moderate predictive values for HF patients. Conclusion: ER stress markers, GRP78 and Caspase-3, had a certain predictive value in HF and can be used as serum biomarkers for the diagnosis of HF. Additionally, GRP78 showed a certain predictive value in HF severity.

Irisin alleviates high glucose-induced hypertrophy in H9c2 cardiomyoblasts by inhibiting endoplasmic reticulum stress.

BACKGROUND: Endoplasmic reticulum stress (ERS) plays an important role in the process of myocardial hypertrophy in diabetic cardiomyopathy (DCM). Irisin, a novel cytokine, has been found to protect against cardiac diastolic dysfunction in DCM. We aimed to investigate the role of irisin in cardiac hypertrophy and to elucidate the underlying mechanisms. METHODS: H9c2 cells were induced with 33 mM glucose to construct a cardiac hypertrophy cell model, which was then treated with irisin in the presence or absence of the ERS inducer tunicamycin (TM). The cell surface area was measured by FITC-phalloidin staining. The atrial natriuretic peptide levels were detected by an enzyme-linked immunosorbent assay. Furthermore, the expression of the ERS-related proteins, P-PERK, PERK, IRE1α and GRP78, was detected by western blotting. RESULTS: Irisin significantly reduced myocardial hypertrophy and suppressed high glucose (HG)-induced oxidative stress. Meanwhile, the protective effect of irisin on cardiomyoblasts was reversed by the ERS inducer, TM. Additionally, we detected ERS-associated signaling pathway proteins and found that irisin significantly reduced the protein expression levels of GRP78 and p-PERK/PERK. CONCLUSION: These results suggest that irisin ameliorates HG-induced cardiac hypertrophy by inhibiting ERS.

Serum irisin levels in patients with myasthenia gravis.

OBJECTIVE: Myasthenia gravis (MG) is an autoimmune disorder whose main symptoms are muscle weakness and fatigue. Irisin is a novel skeletal muscle-derived myokine participating in several physiological and pathological processes. The initial objective of the project was to explore serum levels of irisin in patients with MG, as well as its correlation with disease severity. METHODS: We retrospectively evaluated serum levels of irisin in 77 MG patients and 57 healthy controls (HCs) by enzyme-linked immunosorbent assay. Further, clinical parameters were measured properly. RESULTS: Serum irisin levels were significantly elevated in MG patients compared with HCs (p < 0.001). Furthermore, serum irisin levels were associated with the myasthenia gravis activities of daily living score in ocular myasthenia gravis (OMG) patients (r = 0.476, p = 0.004), but there was no relationship to be considered of any relevant value in generalized myasthenia gravis (GMG) patients. Acetylcholine receptor antibody-positive MG patients had higher serum irisin levels compared with HCs. Thymoma, endotracheal intubation, or intensive care unit treatments subsequently were not found to have effect on serum levels of irisin, but tendencies of increase were observed in negative ones. CONCLUSIONS: Serum irisin levels were elevated in patients with MG, suggesting its possible involvement in MG. And irisin is expected to be a signal to evaluate the activities of daily living of OMG patients, while its effect needs further study.

Roles of IL-35-producing T and B cells in anti-acetylcholine receptor antibody-positive myasthenia gravis.

BACKGROUND: Interleukin 35 (IL-35) plays an anti-inflammatory in numerous autoimmune diseases. However, the potential roles of IL-35-producing T and B cells and serum IL-35 levels in the pathogenesis of myasthenia gravis (MG) and its association with disease activity in patients with MG remain unclear. METHODS: The percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells among peripheral blood mononuclear cells were determined in 37 patients with anti-acetylcholine receptor (AChR) antibody-positive MG and 35 healthy controls (HCs) by performing a flow cytometry analysis. Serum IL-35 levels in participants were determined using an enzyme-linked immunosorbent assay. Further, the correlations between IL35 levels and disease activity were analysed. RESULTS: The percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells were significantly lower in patients with anti-AChR antibody-positive MG than in HCs (p = 0.001 and p = 0.002, respectively). Furthermore, patients with thymoma and patients with generalized MG had lower percentages of IL-35-producing CD4 + CD25 + T cells and CD19 + B cells than those without thymoma and those with ocular MG (p = 0.001 and p = 0.003; p = 0.008 and p = 0.001, respectively). Interestingly, the suppression of IL-35 secretion correlated negatively with the activities of daily living scores of patients with MG (r = -0.4774, p = 0.0028) and the quantitative MG scores (r = -0.4656, p = 0.0037). The proportions of IL-35-producing T cells and B cells and serum levels of IL-35 increased after treatment. CONCLUSIONS: IL-35 may represent a potential biomarker for the clinical evaluation of MG.

Irisin levels in the serum and cerebrospinal fluid of patients with multiple sclerosis and the expression and distribution of irisin in experimental autoimmune encephalomyelitis.

Irisin is a novel hormone-like myokine that plays an important role in central nervous system (CNS) diseases, such as cerebral ischaemia and Alzheimer's disease. However, irisin is rarely investigated in multiple sclerosis (MS), a typical inflammatory demyelinating disease of the CNS, and in experimental autoimmune encephalomyelitis (EAE), a typical model of MS. We determined the levels of irisin in the serum and cerebrospinal fluid in patients with MS. The expression and histological distribution of irisin were determined in EAE. Serum irisin levels in patients with MS and in EAE mice were increased, and the levels of FNDC5/irisin mRNA were decreased in the spinal cord and brain regardless of the onset, peak or chronic phase of EAE. Immunofluorescence staining showed co-localization of irisin and neurones. The levels of irisin fluctuated with disease progression in MS and EAE. Irisin may be involved in the pathological process of MS/EAE.

Lower levels of irisin in patients with type 2 diabetes mellitus: A meta-analysis.

AIMS: This study aimed to provide evidence on the levels of circulating irisin in patients with type 2 diabetes mellitus (T2DM). METHODS: A meta-analysis was conducted to compare the irisin levels in patients with T2DM with the levels in control patients. PubMed, Embase, CENTRAL databases, and other sources were searched from inception through September 2020. Review manager software version 5.4 was used to calculate the pooled outcomes. Heterogeneity was measured using I2 statistics. RESULTS: Twenty-six studies involving 3667 participants met the inclusion criteria and were analyzed in this study. We found that irisin levels were significantly lower in patients with T2DM [Standard (Std.) Mean Difference, -1.02; 95% confidence interval (95% CI), -1.37 to -0.67; p < 0.00001]. Sensitivity analysis confirmed the robustness of this result (Std. Mean Difference, -0.56; 95% CI, -0.73 to -0.39; p < 0.00001). CONCLUSIONS: As compared to the control group and irrespective of differences in ethnicities, age groups, study designs, blood samples, sample sizes, language used for the study, or ELISA kits, lower levels of irisin were observed in patients with T2DM.

Irisin improves insulin resistance by inhibiting autophagy through the PI3K/Akt pathway in H9c2 cells.

As an important complication of diabetes mellitus, diabetic cardiomyopathy (DCM) is thought to arise as a result of insulin resistance (IR) in cardiomyocytes. Improving IR in cardiomyocytes may therefore be a way to treat DCM. A recently discovered myokine, irisin, has been shown to be significantly associated with increased insulin sensitivity both in clinical and pre-clinical studies of diabetes mellitus. Based on previously research, we hypothesized that irisin may be a potential candidate for increasing the insulin sensitivity of cardiomyocytes. The aim of the present study was to examine the ability of irisin to affect IR induced by treatment of rat cardiomyocyte H9c2 cells with palmitic acid (PA) and to explore its underlying mechanism. Differentiated H9c2 cells were treated with 500 µM PA, 200 ng/mL irisin, and 500 µM PA + 200 ng/mL irisin with or without 100 nM rapamycin (RAP) for 24 h. We found that coincubation with 200 ng/mL irisin for 24 h significantly increased insulin-stimulated glucose consumption compared to the 500 µM PA group alone. Additionally, coincubation with irisin significantly alleviated the degree of autophagy compared to the 500 µM PA group alone as evidenced by monodansylcadaverine (MDC) fluorescence, the LC3II/LC3I protein levels ratio, and the protein levels of Atg5 and Atg7. Coincubation with irisin increased the levels of PI3Kp110α, pAkt and Akt compared to the 500 µM PA group alone. All these effects of irisin were reversed by RAP. Our results indicate that irisin improves IR in H9c2 cells, possibly in part by inhibiting autophagy through activating the PI3K/Akt pathway.

Interleukin-27 levels in patients with myasthenia gravis.

Interleukin-27 (IL-27), which belongs to IL-12 family, influences the function of T cells (Tregs) through regulating the expression, and function of forkhead box P3 (FoxP3). In this study, we detected the IL-27 serum levels in 59 myasthenia gravis (MG) patients and 35 healthy controls (HCs). Among them, 32 MG patients received immunoglobulin intravenous (IVIG) injections (0.4 g/kg per day for 5 consecutive days). IL-27 levels were collected before and after the treatments and subjected to a comparative study. Finally, we assessed the correlations of IL-27 levels with the clinical characteristics of MG. As a result, serum IL-27 levels were significantly higher in MG patients than those in the HCs. Meanwhile, significant reduction was detected after the IVIG treatment. IL-27 levels positively correlated with both MG activities of daily living and quantitative MG score. IL-27 may participate in the pathogenesis of MG and can be used as an early marker for the diagnosis and prognosis of MG. In addition, IL-27 can be used as a target for MG treatment through the regulation of specific immune signaling and maintaining immune homeostasis.

Increased Cerebrospinal Fluid Uric Acid Levels in Guillain-Barré Syndrome.

Uric acid (UA) is a natural scavenger for peroxynitrite and can reflect antioxidant activity and oxidative stress in several neurological disorders. Changes in serum and cerebrospinal fluid (CSF) levels of UA have been reported in patients with multiple sclerosis and neuromyelitis optica spectrum disorders. The levels of UA in CSF are relatively poorly understood in patients with Guillain-Barré syndrome (GBS). It remains unclear whether UA can play an antioxidant role and reflect oxidative stress in GBS. The purpose of this study is to investigate CSF and serum UA levels in patients with GBS and their relationship with clinical characteristics. The CSF and serum UA levels were detected in 43 patients with GBS, including 14 acute inflammatory demyelinating polyneuropathy (AIDP), 6 acute motor axonal neuropathy (AMAN), 13 with acute motor and sensory axonal neuropathy (AMSAN), 7 Miller Fisher syndrome (MFS), and 3 unclassified, and 25 patients with non-inflammatory neurological disorders (NIND) as controls. Moreover, serum UA levels were also detected in 30 healthy controls. The levels of UA were measured using uricase-based methods with an automatic biochemical analyzer. CSF UA levels were significantly increased in patients with GBS (p = 0.011), particularly in patients with AIDP (p = 0.004) when compared with NIND. Among patients with GBS, CSF UA levels were higher in those with demyelination (p = 0.022), although the difference was not significant after multiple testing correction. CSF UA levels in GBS were positively correlated with serum UA levels (r = 0.455, p = 0.022) and CSF lactate (r = 0.499, p = 0.011). However, no significant correlations were found between CSF UA levels and GBS disability scores. There were no significant differences in serum UA levels among GBS, NIND, and healthy controls. These results suggest that CSF UA may be related to the pathogenesis of demyelination in patients with GBS and may be partially determined by serum UA and the impaired blood-nerve barrier.

Increased cerebrospinal fluid YKL-40 levels are associated with disease severity of neuromyelitis optica spectrum disorders.

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) is a severe immune-mediated inflammatory central nervous system (CNS) syndrome. YKL-40, as a new inflammatory marker, has been studied in many autoimmunity and CNS diseases. Our aim of this study was to investigate cerebrospinal fluid (CSF) and serum YKL-40 levels in patients with NMOSD and their association with disease severity. METHODS: We measured CSF and serum YKL-40 levels in 29 patients with NMOSD and 21 age- and sex-matched controls. We analyzed the associations between CSF YKL-40 levels and the clinical variables of NMOSD. RESULTS: Compared to controls, patients with NMOSD had significantly higher CSF YKL-40 levels. Moreover, CSF YKL-40 levels were positively correlated with the Expanded Disability Status Scale scores. CONCLUSIONS: YKL-40 could be a NMOSD severity biomarker and a potential target for NMOSD treatment.

Elevated resistin levels may regulate high mobility group box 1 expression in Guillain-Barré syndrome.

Interactions among cytokines have important roles in the inflammatory processes underlying Guillain-Barré syndrome (GBS). Resistin and high mobility group box 1 (HMGB1) are involved in many inflammatory processes. This study examined 51 GBS patients, and found that serum resistin levels were elevated in 51 patients with GBS and correlated with HMGB1 levels. In vitro, resistin induced the release of HMGB1, interleukin (IL)-1ß, and IL-6 in THP-1 macrophages. This process was dependent on activation of p38 mitogen-activated protein kinase and NF-κB signaling pathways. These results suggest that signaling between resistin and HMGB1 might be a potential therapeutic target in GBS.

Valproic acid, targets papillary thyroid cancer through inhibition of c-Met signalling pathway.

Tyrosine kinase receptors such as c-Met and its ligands are interesting therapeutic targets that have been reported to be involved in the progression of several types of cancers. Histone deacetylase inhibitor, valproic acid (VPA) is one such compound with promising anti-cancer properties. The current study was designed to evaluate the c-Met activity of VPA in thyroid carcinoma. A total 36 nu/nu mice with SW1736 cells-induced tumours were randomised into three treatment groups (5, 15, 30 mg/kg/day p.o. VPA; n = 9/group). Various cellular and enzymatic assays were performed to evaluate the dose-response relationship of VPA in c-Met inhibition. In vitro assays revealed that VPA (IC50, 5-26 nmol/l) shows c-Met phosphorylation and c-Met-dependent inhibition of cellproliferation. This causes inhibition of downstream signalling pathways in human thyroid cancer cell lines (SW1736, WRO). Additionally, VPA also showed anti-angiogenetic activity in HGF-stimulated endothelial cell. VPA showed significant reduction in tumour size in xenograft model (P = 0.023) with high levels of c-Met expression. The anticancer activity was found to be dose dependent and strongly correlated with c-Met expression. Thus, this novel finding paves way for investigation of new mechanism of action and its validation in clinical settings.

Anti-hepatocarcinoma activity of TT-1, an analog of melittin, combined with interferon-α via promoting the interaction of NKG2D and MICA.

Hepatocarcinoma is one of the malignant cancers with significant morbidity and mortality. Immunotherapy has emerged in clinical treatment, owing to the limitation and severe side effects of chemotherapy. In the immune system, natural killer (NK) cells are important effectors required to eliminate malignant tumor cells without the limitation of major histocompatibility complex (MHC) molecule issues. Hence, treatment which could stimulate NK cells is of great interest. Here, we investigated the efficacy of the combined therapy of TT-1 (a mutant of melittin) and interferon-α (IFN-α) on NK cells and human liver cancer HepG-2/Huh7 cells in vitro and in vivo, as well as the mechanism involved. The combination therapy significantly inhibited the growth of HepG-2/Huh7 cells in vivo, but this effect was impaired after depleting NK cells. TT-1 not only up-regulated MHC class I-related chain molecules A (MICA) expression, but also prevented the secretion of soluble MICA (sMICA). Both the mRNA and protein of a disintegrin and metallopeptidase 10 (ADAM 10) in HepG-2/Huh7 cells were decreased after TT-1 treatment. The combined therapy of TT-1 and IFN-α could suppress the growth of HepG-2/Huh7 xenografted tumor effectively via promoting the interaction of NK group 2, member D (NKG2D) and MICA, indicating that TT-1+IFN-α would be a potential approach in treating liver cancer.

Analysis of serum interleukin-27 and interleukin-35 concentrations in patients with Guillain-Barré syndrome.

BACKGROUNDS: Guillain-Barré syndrome (GBS) is a postinfectious immune-mediated peripheral neuropathy. Interleukin (IL)-27 and IL-35 have been recognized as novel members of IL-12 family. We evaluated the serum and cerebral spinal fluid (CFS) concentrations of IL-27 and IL-35 in GBS and analyze their correlations with clinical characteristics. METHODS: Serum samples from 50 patients with GBS including 9 acute inflammatory demyelinating polyradiculoneuropathy (AIDP), 33 acute motor axonal neuropathy (AMAN) and 8 unclassified and 35 age- and sex-matched healthy controls were collected. Thirty CSF samples from these patients and 25 patients with other noninflammatory neurological disorders (ONNDs) as disease controls were collected after lumbar puncture. Serum and CSF IL-27 and IL-35 concentrations were measured using human IL-27 or IL-35 ELISA. RESULTS: Serum IL-27 concentrations were elevated (p=0.002) whereas serum IL-35 concentrations were decreased (p=0.031) in patients with GBS comparing with healthy controls, particularly in patients exhibiting AMAN (p=0.012). Additionally, serum IL-35 concentrations were negatively correlated with disease severity and outcomes in patients with AMAN (r=-0.358, p=0.041; r=-0.416, p=0.016). CONCLUSIONS: IL-27 might be pathogenic, whereas IL-35 be protective in GBS. Additionally, serum IL-35 concentrations may be important biomarkers for the severity and outcomes of AMAN.

Distinctive characteristics of early-onset and late-onset neuromyelitis optica spectrum disorders.

OBJECTIVES: Little is known about patients with neuromyelitis optica spectrum disorders (NMOSD) as defined by onset age. This study aimed to analyze the different demographic, clinical, laboratory, and magnetic resonance imaging (MRI) characteristics in early-onset (≤50 years) NMOSD (EONMOSD) and late-onset (>50 years) NMOSD (LONMOSD). MATERIALS AND METHODS: We enrolled 142 patients with NMOSD from Tianjin Medical University General Hospital, Tianjin, China, and categorized them into two groups according to the age of onset: EONMOSD and LONMOSD. Demographic, clinical, laboratory, and MRI characteristics were collected and compared between the two groups. Serum aquaporin-4 (AQP4) antibody levels were determined by cell-based assay and fluorescence immunoprecipitation assays. RESULTS: Among the patients studied, 83 had early onset (≤50 years) and 59 had late onset (>50 years) of NMOSD. As compared with LONMOSD, EONMOSD patients had more severe visual disability according to functional scores in clinical parameters, significantly lower C3 and C4 serum levels, more frequent cervical lesions, and more lesions around the fourth ventricle, but fewer lesions in hemispheric white matter. LONMOSD patients suffered more motor and sensory disability than EONMOSD patients. CONCLUSIONS: In NMOSD, the clinical, laboratory, and MRI features differ according to age of onset, suggesting that differences in pathogenesis and treatment should be further investigated.

Olfactory dysfunction in patients with multiple sclerosis.

Association of changes in olfactory-related structures with olfactory function in patients with multiple sclerosis (MS) is not well understood. We used a T&T olfactometer test kit to evaluate olfactory function in 26 patients with MS and 26 age- and sex-matched healthy controls (HC). Then, Brain MRI were performed and olfactory-related structures were analyzed in these subjects. Olfactory detection and recognition threshold were significantly higher in the MS group, interestingly olfactory recognition threshold positively correlated with expanded disability status scale scores in these patients. Olfactory bulb (OB) volume reduced in patients with olfactory dysfunction (ODF). At the same time, reductions in gray matter (GM) volume were observed in the parahippocampal gyrus (PCG), amygdala, piriform cortex, and inferior frontal gyrus in patients with MS compared to HC. Atrophy of the PCG was more obvious in patients with ODF than patients without ODF and the PCG volume correlated with the olfactory recognition threshold, while no difference was found in fractional anisotropy values of tract-based spatial statistics analysis in the two groups. Olfactory function in patients with MS tends to become gradually more impaired with disability aggravation. Decreases in the volume of the OB and olfactory-related GM might provide valuable information about disease status in patients with MS with olfactory impairment.

Exclusive real-time monitoring during recurrent laryngeal nerve dissection in conventional monitored thyroidectomy.

During conventional intermittent intraoperative neuromonitoring (IONM) in thyroidectomy, recurrent laryngeal nerve (RLN) injury is detected by an electromyographic (EMG) loss of signal (LOS) after the nerve dissection. Exclusive continuous monitoring during the phase of RLN dissection may be helpful in detecting adverse EMG changes earlier. A total of 208 RLNs at risk were enrolled in this study. Standardized IONM procedures were followed. We continuously stimulated the RLN at the lower exposed end with a stimulator to exclusively monitor the real-time quantitative EMG change during RLN dissection. Once the amplitude decreased by more than 50% of the initial signal, the surgical maneuver was paused and the RLN was retested every minute for 10 minutes to determine amplitude recovery before restarting the dissection. The procedure was feasible in all patients. No LOS was encountered in this study. Nineteen RLNs had an amplitude reduction of more than 50%. Eighteen nerves showed gradual amplitude recovery (16 nerves had a traction injury and two nerves had a compression injury). After 10 minutes, the recovery was complete (i.e., >90%) in eight nerves, 70-90% in seven nerves, and 50-70% in three nerves. Among these 18 nerves, only one nerve developed temporary vocal palsy because it was exposed to unavoidable repeated nerve traction after restarting the dissection. Another nerve showed no gradual recovery from thermal injury, and developed temporary vocal palsy. The temporary and permanent palsy rates were 1% and 0%, respectively. During intermittent IONM, exclusive real-time monitoring of the RLN during dissection is an effective procedure to detect an adverse EMG change, and prevent severe RLN injuries that cause LOS.

Decreased serum IL-27 and IL-35 levels are associated with disease severity in neuromyelitis optica spectrum disorders.

The interleukin 12 (IL-12) family plays important roles in autoimmune diseases. To explore the roles of the IL-12 family members IL-27 and IL-35 in the pathogenesis of neuromyelitis optica spectrum disorders (NMOSD), we determined their serum and cerebral spinal fluid levels and assessed potential correlations with clinical characteristics. Serum IL-27 levels were negatively correlated with disease severity and spinal cord lesion length, while serum IL-35 levels were negatively correlated with disease severity and annual relapse rate. Thus, IL-27 and IL-35 may be important biomarkers of NMOSD severity and these molecules might represent potential therapeutic cytokines for treating NMOSD.