FTO (Fat-Mass and Obesity-Associated Protein) Participates in Hemorrhage-Induced Thalamic Pain by Stabilizing Toll-Like Receptor 4 Expression in Thalamic Neurons.

Background and Purpose: Hemorrhage-caused gene changes in the thalamus likely contribute to thalamic pain genesis. RNA N6-methyladenosine modification is an additional layer of gene regulation. Whether FTO (fat-mass and obesity-associated protein), an N6-methyladenosine demethylase, participates in hemorrhage-induced thalamic pain is unknown. Methods: Expression of Fto mRNA and protein was assessed in mouse thalamus after hemorrhage caused by microinjection of Coll IV (type IV collagenase) into unilateral thalamus. Effect of intraperitoneal administration of meclofenamic acid (a FTO inhibitor) or microinjection of adeno-associated virus 5 (AAV5) expressing Cre into the thalamus of Ftofl/fl mice on the Coll IV microinjection­induced TLR4 (Toll-like receptor 4) upregulation and nociceptive hypersensitivity was examined. Effect of thalamic microinjection of AAV5 expressing Fto (AAV5-Fto) on basal thalamic TLR4 expression and nociceptive thresholds was also analyzed. Additionally, level of N6-methyladenosine in Tlr4 mRNA and its binding to FTO or YTHDF2 (YTH N6-methyladenosine RNA binding protein 2) were observed. Results: FTO was detected in neuronal nuclei of thalamus. Level of FTO protein, but not mRNA, was time-dependently increased in the ipsilateral thalamus on days 1 to 14 after Coll IV microinjection. Intraperitoneal injection of meclofenamic acid or adeno-associated virus-5 expressing Cre microinjection into Ftofl/fl mouse thalamus attenuated the Coll IV microinjection­induced TLR4 upregulation and tissue damage in the ipsilateral thalamus and development and maintenance of nociceptive hypersensitivities on the contralateral side. Thalamic microinjection of AAV5-Fto increased TLR4 expression and elicited hypersensitivities to mechanical, heat and cold stimuli. Mechanistically, Coll IV microinjection produced an increase in FTO binding to Tlr4 mRNA, an FTO-dependent loss of N6-methyladenosine sites in Tlr4 mRNA and a reduction in the binding of YTHDF2 to Tlr4 mRNA in the ipsilateral thalamus. Conclusions: Our findings suggest that FTO participates in hemorrhage-induced thalamic pain by stabilizing TLR4 upregulation in thalamic neurons. FTO may be a potential target for the treatment of this disorder.

MG53 Protects against Sepsis-Induced Myocardial Dysfunction by Upregulating Peroxisome Proliferator-Activated Receptor-α.

BACKGROUND: The heart is one of the most commonly affected organs during sepsis. Mitsugumin-53 (MG53) has attracted attention in research due to its cardioprotective function. However, the role of MG53 in sepsis-induced myocardial dysfunction (SIMD) remains unknown. The purpose of this study was to explore the underlying mechanism of MG53 in SIMD and investigate its potential relationship with peroxisome proliferator-activated receptor-α (PPARα). METHODS: The cecal ligation and puncture (CLP) model was created to induce SIMD in rats. Protein levels of MG53 and PPARα, cardiac function, cardiomyocyte injury, myocardial oxidative stress and inflammatory indicators, and cardiomyocyte apoptosis were measured at 18 h after CLP. The effects of MG53 on PPARα in SIMD were investigated via preconditioning recombinant human MG53 (rhMG53) and PPARα antagonist GW6471. RESULTS: The expression of MG53 and PPARα sharply decreased in the myocardium at 18 h after CLP. Compared with the sham group, cardiac function was significantly depressed, which was associated with the destructed myocardium, upregulated oxidative stress indicators and proinflammatory cytokines, and excessive cardiomyocyte apoptosis in the CLP group. Supplementation with rhMG53 enhanced myocardial MG53, increased the survival rate with improved cardiac function, and reduced oxidative stress, inflammation, and myocardial apoptosis, which were associated with PPARα upregulation. Pretreatment with GW6471 abolished the abovementioned protective effects induced by MG53. CONCLUSIONS: Both MG53 and PPARα were downregulated after sepsis shock. MG53 supplement protects the heart against SIMD by upregulating PPARα expression. Our results provide a new treatment strategy for SIMD.

Neoadjuvant everolimus plus letrozole versus fluorouracil, epirubicin and cyclophosphamide for ER-positive, HER2-negative breast cancer: study protocol for a randomized pilot trial.

BACKGROUND: The response to neoadjuvant chemotherapy (NAC) varies by estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) statuses, with responses being lower in ER-positive, HER2-negative tumors as compared with ER-negative, HER2-positive or triple-negative tumors. Neoadjuvant endocrine therapy (NET) is an attractive alternative to NAC for ER-positive, HER2-negative cancer. However, a prior trial comparing NET with standard NAC in ER-positive tumor showed that the difference of response was not significant. Studies demonstrated that the mTOR inhibitor everolimus could sensitize breast tumors to endocrine therapy. A pilot open-label, randomized trial has been designed to evaluate the feasibility, efficacy and tolerability of neoadjuvant everolimus plus letrozole versus NAC in treating postmenopausal women with ER-positive, HER2-negative breast cancer. METHODS: Forty postmenopausal women with non-metastatic ER-positive, HER2-negative invasive breast cancer with a primary tumor > 2 cm or positive axillary lymph node(s) proved by biopsy will be randomly (1:1) enrolled from Sun Yat-Sen Memorial Hospital to receive neoadjuvant everolimus plus letrozole for 18 weeks or fluorouracil, epirubicin plus cyclophosphamide (FEC) for six cycles before surgery. Primary outcome is the feasibility of the trial. Secondary outcome measures include ultrasound response rate, pathological complete response rate, breast-conserving surgery rate, toxicities, and changes in the percentages of peripheral blood CD4+ T cells, CD8+ T cells, T helper cells, regulatory T cells, and NK cells. DISCUSSION: This is the first study to determine the feasibility, efficacy and tolerability of head-to-head neoadjuvant everolimus plus letrozole versus neoadjuvant FEC in treating postmenopausal women with ER-positive, HER2-negative breast cancer. The trial will provide evidence to assess the feasibility of a future multicenter, randomized controlled trial, and will provide valuable clinical data of the immunoregulatory effect of everolimus in breast cancer. TRIAL REGISTRATION: ClinicalTrials.gov registry, ID: NCT02742051 . Registered on 7 April 2016.

Curcumin exerts antinociceptive effects by inhibiting the activation of astrocytes in spinal dorsal horn and the intracellular extracellular signal-regulated kinase signaling pathway in rat model of chronic constriction injury.

BACKGROUND: Activation of glial cells and the extracellular signal-regulated kinase (ERK) signaling pathway play an important role in the development and maintenance of neuropathic pain. Curcumin can alleviate the symptom of inflammatory pain by inhibiting the production and release of interleukin and tumor necrosis factor. However, whether curcumin affects neuropathic pain induced by nerve injury and the possible mechanism involved are still unknown. This study investigated the effects of tolerable doses of curcumin on the activation of astrocytes and ERK signaling in the spinal dorsal horn in rat model of neuropathic pain. METHODS: Adult male Sprague-Dawley rats were randomly divided into three groups: a control (sham operated) group, and chronic constriction injury groups (to induce neuropathic pain) that were either untreated or treated with curcumin. Thermal and mechanical hyperalgesia thresholds were measured. The distribution and morphological changes of astrocytes were observed by immunofluorescence. Western blotting was used to detect changes in the expression of glial fibrillary acid protein (GFAP) and phosphorylated ERK. RESULTS: Injured rats showed obvious mechanical allodynia and thermal hyperalgesia. The number of GFAP-positive astrocytes, and the fluorescence intensity of GFAP were significantly increased in the spinal dorsal horn of injured compared with control rats. The soma of astrocytes also appeared hypertrophied in injured animals. Expression of GFAP and phosphorylated ERK was also significantly increased in the spinal dorsal horn of injured compared with control rats. Curcumin reduced the injury-induced thermal and mechanical hyperalgesia, the increase in the fluorescence intensity of GFAP and the hypertrophy of astrocytic soma, activation of GFAP and phosphorylation of ERK in the spinal dorsal horn. CONCLUSIONS: Curcumin can markedly alleviate nerve injury-induced neuropathic pain in rats. The analgesic effect of curcumin may be attributed to its inhibition of astrocyte hypertrophy in the spinal dorsal horn and phosphorylation of the ERK signaling pathway.