Inhibition of activated astrocyte ameliorates lipopolysaccharide- induced depressive-like behaviors

Background and Purpose:
Increasing evidence suggests systemic inflammation-caused skeletal muscle atrophy as a major clinical feature of cachexia Triptolide obtained from Tripterygium wilfordii Hook F possesses potent anti-inflammatory and immunosuppressive effects The present study aims to evaluate the protective effects and molecular mechanisms of triptolide on inflammation-induced skeletal muscle atrophy

Experimental Approach:
The effects of triptolide on skeletal muscle atrophy were investigated in LPS-treated C2C12 myotubes and C57BL/6 mice Protein expressions and mRNA levels were analysed by western blot and qPCR, respectively Skeletal muscle mass, volume and strength were measured by histological analysis, micro-CT and grip strength, respectively Locomotor activity was measured using the open field test

KEY RESULTS:
Triptolide (10–100 fM) up-regulated protein synthesis signals (IGF-1/p-IGF-1R/IRS-1/p-Akt/p-mTOR) and down-regulated protein degradation signal atrogin-1 in C2C12 myotubes In LPS (100 ng·ml−1)-treated C2C12 myotubes, triptolide up-regulated MyHC, IGF-1, p-IGF-1R, IRS-1 and p-Akt Triptolide also down-regulated ubiquitin-proteasome molecules (n-FoxO3a/atrogin-1/MuRF1), proteasome activity, autophagy-lysosomal molecules (LC3-II/LC3-I and Bnip3) and inflammatory mediators (NF-κB, Cox-2, NLRP3, IL-1β and TNF-α) However, AG1024, an IGF-1R inhibitor, suppressed triptolide-mediated effects on MyHC, myotube diameter, MuRF1 and p62 in LPS-treated C2C12 myotubes In LPS (1 mg·kg−1, ip)-challenged mice, triptolide (5 and 20 μg·kg−1·day−1, ip) decreased plasma TNF-α levels and it increased skeletal muscle volume, cross-sectional area of myofibers, weights of the gastrocnemius and tibialis anterior muscles, forelimb grip strength and locomotion

Conclusions and Implications:
These findings reveal that triptolide prevented LPS-induced inflammation and skeletal muscle atrophy and have implications for the discovery of novel agents for preventing muscle wasting

Triptolide prevents LPS-induced skeletal muscle atrophy via inhibiting NF-κB/TNF-α and regulating protein synthesis/degradation pathway.

Lipopolysaccharides (LPS) are proinflammation mediators that can induce the inflammatory model of the hippocampal neuron, and neuroinflammation participates in the pathophysiology of depression. Xiaoyao Pill is a classical Chinese medicine formula that has been used for the treatment of mental disorders such as depression in China since the Song dynasty. We established a hippocampal neuronal cell inflammation model by LPS and investigate the intervention effect and mechanism of Xiaoyao Pills. The expression levels of IL-6, TNF-α, IDO, 5-HT, brain-derived neurotrophic factor, and β-nerve growth factor were detected by enzyme-linked immunosorbent assay. mRNA levels of IL-6, TNF-α, 5-HT1A, IDO-1, brain-derived neurotrophic factor, nerve growth factor, tropomyosin receptor kinase B, tropomyosin receptor kinase A, and cAMP response element-binding protein were detected by reverse transcription-polymerase chain reaction. To further validate, protein expression was determined by western blot and immunofluorescence. Lipopolysaccharide-induced neuroinflammatory state resulted in the release of IL-6, TNF-α, and IDO and a decrease of BDNF, NGF, TrkB, TrkA, CREB, p-CREB, p-CREB/CREB, and SYP and inhibited hippocampal neurogenesis in the hippocampal neuron. Xiaoyao Pills significantly decreased the levels of IL-6, TNF-α, and IDO in cell supernatant and increased the expression of BDNF, NGF, TrkB, TrkA, CREB, p-CREB, p-CREB/CREB, and SYP as well as the average optical density of BrdU/NeuN double-labelled positive cells. Our study shows that lipopolysaccharides induce inflammation and nerve damage in hippocampal neurons, which are closely related to the pathological mechanism of depression. Xiaoyao Pills (XYW) play an important neuroprotective effect, which is related to its inhibition of neuronal inflammation and promoting the recovery of nerve injury. These results provide a pharmacologic basis for the treatment of depression of XYW in clinical application.

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Xiaoyao Pills Attenuate Inflammation and Nerve Injury Induced by Lipopolysaccharide in Hippocampal Neurons In Vitro.

Objective This study aimed at investigating the therapeutic effect and mechanism of pioglitazone metformin complex preparation (PM) in polycystic ovary syndrome (PCOS) comorbid psychological distress. Methods Seventy-five patients with PCOS comorbid psychological distress were randomly allocated into the PM, metformin, and placebo groups. The primary efficacy measure was the change from baseline to week 12 on the Symptom Checklist 90-R (SCL-90-R) scores. NLRP3 inflammasome, IL-1β, IL-6, TNF-α, and biochemical parameters were determined at baseline and at week 12. The participants were required to meet the criteria for PCOS (Rotterdam, NIH) and psychological distress (any factor scores of SCL - 90 - R > 2). Results The participants had significantly high scores on the SCL-90-R scales of anxiety and depression. PM significantly decreased anxiety and depression symptom severity (from 2.31 ± 0.75 to 1.65 ± 0.38, p < 0.001, and from 2.08 ± 0.74 to 1.61 ± 0.46, p = 0.010, at week 12, respectively). PM significantly decreased the expression of NRPL3 and caspase-1. Patients in the PM group experienced a significant reduction in IL-1β (from 98.42 ± 14.38 to 71.76 ± 13.66, p = 0.02), IL-6 (from 87.51 ± 8.74 to 71.98 ± 15.87, p = 0.02), and TNF-α (from 395.33 ± 88.55 to 281.98 ± 85.69, p = 0.04). PM was superior to metformin in reducing total testosterone (2.24 ± 0.74 versus 3.06 ± 0.83, p = 0.024, at week 12). Conclusions This study is the first to reveal that PM alleviates psychological distress via inhibiting NLRP3 inflammasome and improves several markers, including total testosterone.

/pdf/pioglitazone-metformin-complex-improves-polycystic-ovary-3luw552vfa.pdf

Pioglitazone Metformin Complex Improves Polycystic Ovary Syndrome Comorbid Psychological Distress via Inhibiting NLRP3 Inflammasome Activation: A Prospective Clinical Study.

The resilient phenotype elicited by ketamine against inflammatory stressors-induced depressive-like behavior is associated with NLRP3-driven signaling pathway.

Evidence suggests that inflammation and neurogenesis play an important role in major depressive disorder (MDD). Mahuang-Fuzi-Xixin decoction (MFX), as the traditional Chinese prescription, has been widely applied for asthma, migraine, and MDD in clinics. However, the effects of MFX on the potential mechanism in MDD are still unclear. Hence, the present study is aimed at exploring whether the antidepressive effect of MFX is connected to the anti-inflammatory and promoting neurogenesis. Besides, lipopolysaccharide (LPS) of Gram-negative bacteria can induce depressive-like behaviors. We demonstrated that administration of MFX corrected the depressive-like behaviors in LPS-induced mice and significantly decreased the expression of IL-1β in the hippocampus. LPS injection induced a significant increase in the levels of NLRP3, cleaved caspase-1 p20, and ASC in the hippocampus, as well as Trx-interacting protein (TXNIP), and MFX could reverse this change. What is more, treatment of MFX increased the level of doublecortin (DCX), brain-derived neurotrophic factor (BDNF), and tropomyosin-related kinase receptor B (TrkB) in the hippocampus which means that MFX could promote the neurogenesis. In conclusion, the study indicates that MFX relieves a depressive-like state in LPS-induced mice through the inhibition of the NLRP3 inflammasome and the enhancement of the neurogenesis pathway.

/pdf/mahuang-fuzi-xixin-decoction-reverses-depression-like-2wioi92riz.pdf

Mahuang-Fuzi-Xixin Decoction Reverses Depression-Like Behavior in LPS-Induced Mice by Regulating NLRP3 Inflammasome and Neurogenesis.

In vitro inhibitory effects of components from Salvia miltiorrhiza on catalytic activity of three human AA ω-hydroxylases

Epoxide hydrolases catalyze the hydrolysis of both exogenous and endogenous epoxides to the corresponding vicinal diols by adding water. Microsomal and soluble epoxide hydrolase are two main mammalian enzymes that have been intensely characterized. The purpose of this investigation was to develop and validate a proteomics assay allowing the simultaneous quantification of microsomal and soluble epoxide hydrolase in rats. Protein quantification was realized through targeted proteomics using liquid chromatography with tandem mass spectrometry for the determination of trypsin-specific surrogate peptides after digestion. Stable isotope-labeled peptides were used as the internal standards. The chromatography of the surrogate peptides was performed on an Agilent SB C18 column (100 mm × 4.6 mm, 1.8 µm) with gradient elution. Acetonitrile containing 0.1% formic acid and 0.1% formic acid aqueous solution were used as mobile phases. A multiple reaction monitoring method in a positive ionization mode was used for the simultaneous detection of the peptides. The method was validated concerning the specificity, linearity, within-day and between-day accuracy and precision, matrix effect, stability, and digestion efficiency. The developed assay was successfully used to quantify the protein levels of microsomal and soluble epoxide hydrolase in rat liver, kidney, and heart S9 samples.

Ying Chen

Papers

Mahuang-Fuzi-Xixin Decoction Reverses Depression-Like Behavior in LPS-Induced Mice by Regulating NLRP3 Inflammasome and Neurogenesis.

In vitro inhibitory effects of components from Salvia miltiorrhiza on catalytic activity of three human AA ω-hydroxylases

Absolute protein assay for the simultaneous quantification of two epoxide hydrolases in rats by mass spectrometry-based targeted proteomics.