Spinal microglial M1 polarization contributes paclitaxel-induced neuropathic pain by triggering cells necroptosis.

Paclitaxel (PTX) is a chemotherapeutic agent that is widely used for the treatment of several types of tumors. However, PTX-induced peripheral neuropathy (PIPN) is an adverse effect generally induced by long-term PTX use that significantly impairs the quality of life. Necroptosis has been implicated in various neurodegenerative disorders. Necroptosis of dorsal root ganglion neurons triggers the pathogenesis of PIPN. Therefore, the present study aims to investigate the role of spinal neuronal necroptosis in PIPN. It also explores the potential role of microglial polarization in necroptosis. We established rat models of PIPN via quartic PTX administration on alternate days (accumulated dose: 8 mg/kg). PTX induced obvious neuronal necroptosis and upregulated the expression of receptor-interacting protein kinase (RIP3) and mixed lineage kinase domain-like protein (MLKL) in the spinal dorsal horn. These effects were inhibited with a necroptosis pathway inhibitor, necrostatin-1 (Nec-1). The effect of microglial polarization on the regulation of spinal necroptosis was elucidated by administering minocycline to inhibit PTX-induced M1 polarization of spinal microglia caused by PTX. We observed a significant inhibitory effect of minocycline on PTX-induced necroptosis in spinal cord cells, based on the downregulation of RIP3 and MLKL expression, and suppression of tumor necrosis factor-α and IL-ß synthesis. Additionally, minocycline improved hyperalgesia symptoms in PIPN rats. Overall, this study suggests that PTX-induced polarization of spinal microglia leads to RIP3/MLKL-regulated necroptosis, resulting in PIPN. These findings suggest a potential target for the prevention and treatment of neuropathic pain.

Research on sweat metabolomics of athlete's fatigue induced by high intensity interval training.

Objective: Sweat is an important specimen of human metabolism, which can simply and non-invasively monitor the metabolic state of the body, and its metabolites can be used as biomarkers for disease diagnosis, while the changes of sweat metabolites before and after exercise-induced fatigue are still unclear. Methods: In this experiment, high-performance chemical isotope labeling liquid chromatography-mass spectrometry (LC-MS) was used to metabolomic 28 sweat samples before and after exercise-induced fatigue of 14 long-distance runners, also IsoMS PRO and SPSS22.0 software were used to analyze the metabolite changes and differential metabolic pathways. Results: A total of 446 metabolites with high confidence were identified, and the sweat metabolome group before and after high-intensity interval exercise-induced fatigue was obvious, among which the upregulated differential metabolites mainly included hypoxanthine, pyruvate, several amino acids, etc., while the downregulated differential metabolites mainly included amino acid derivatives, vitamin B6, theophylline, etc. Conclusion: The change of hypoxanthine concentration in sweat can be used as a good biomarker for the diagnosis of exercise-induced fatigue, while the change of pyruvate content in sweat can be used as a discriminant index for the energy metabolism mode of the body before and after exercise. The main metabolic pathways involved in differential metabolites produced before and after HIIT exercise-induced fatigue are purine metabolism and amino acid metabolism.

Synthesis and bioactivity of new Finasteride conjugate.

Finasteride is a synthetic 4-azasteroid compound that acts by inhibiting type II 5α-reductase, the enzyme that converts the androgen testosterone to 5α-dihydrotestosterone. It was approved by the US FDA for the treatment of benign prostatic hyperplasia and male pattern baldness. Here the acylation product of Finasteride C-18 amide N-polimod was synthesized by employing acylation reaction with polimod amide as a pivotal intermediate. The structure of the key intermediate and target molecule was confirmed by infrared spectrum, (1)H NMR and (13)C NMR spectra and mass spectrum, and the inhibition of the steroid 5α-reductase and the rats' benign prostatic hyperplasia by the new Finasteride conjugate and Finasteride was also determined. The inhibition of the Finasteride conjugate on 5α-reductase was stronger than that of Finasteride. Prostate hyperplasia of rats was reduced by Finasteride conjugate treatment similar to the Finasteride treatment. However, the Finasteride conjugate treated animals showed better viable condition than the Finasteride treated ones, suggesting the new compound may have improved toxicity profile than Finasteride.

Possible Involvement of F1F0-ATP synthase and Intracellular ATP in Keratinocyte Differentiation in normal skin and skin lesions.

The F1F0-ATP synthase, an enzyme complex, is mainly located on the mitochondrial inner membrane or sometimes cytomembrane to generate or hydrolyze ATP, play a role in cell proliferation. This study focused on the role of F1F0-ATP synthase in keratinocyte differentiation, and its relationship with intracellular and extracellular ATP (InATP and ExATP). The F1F0-ATP synthase ß subunit (ATP5B) expression in various skin tissues and confluence-dependent HaCaT differentiation models was detected. ATP5B expression increased with keratinocyte and HaCaT cell differentiation in normal skin, some epidermis hyper-proliferative diseases, squamous cell carcinoma, and the HaCaT cell differentiation model. The impact of InATP and ExATP content on HaCaT differentiation was reflected by the expression of the differentiation marker involucrin. Inhibition of F1F0-ATP synthase blocked HaCaT cell differentiation, which was associated with a decrease of InATP content, but not with changes of ExATP. Our results revealed that F1F0-ATP synthase expression is associated with the process of keratinocyte differentiation which may possibly be related to InATP synthesis.

Changes in plasma concentrations of osteoprotegerin before and after levothyroxine replacement therapy in hypothyroid patients.

CONTEXT: Recent study has shown that overt hypothyroidism (oHT) is associated with increased plasma osteoprotegerin (OPG) levels. OBJECTIVE: Our objective was to examine the plasma OPG level alteration before and after levothyroxine (L-T4) treatment in oHT and subclinical hypothyroidism (sHT). PATIENTS: The study subjects included oHT and sHT patients and healthy individuals (20 subjects in each group). METHODS: All patients were given L-T4 therapy to maintain a euthyroid state. Plasma OPG concentration was measured in duplicate by a sandwich ELISA. RESULTS: Plasma OPG levels in oHT and sHT before treatment were significantly higher than levels in controls (P < 0.01). After normalization of thyroid function, OPG levels in both groups decreased markedly (P < 0.01). The absolute changes in OPG showed a significant positive correlation with the changes in TSH (P < 0.05) and negative correlation with the changes in endothelium-dependent arterial dilation (P < 0.01) in hypothyroid patients during the course of treatment. CONCLUSION: OPG may be involved in the development of vascular dysfunction in hypothyroid patients.

Apolipoprotein e4 allele and the risk of CAD death in type 2 diabetes mellitus with ischaemia electrocardiographic change.

The presence of apolipoprotein (Apo) e4 allele is reported to be associated with the increased risk of coronary artery disease (CAD), as well as the impairment of endothelium-dependent arterial dilation in type 2 diabetes mellitus. Therefore, we hypothesized that Apo e4 allele increases the death risk from coronary artery disease in type 2 diabetes with ischaemia electrocardiographic change. From January 1993 to December 1999, 46 type 2 diabetic patients with e4/4 or e4/3, 96 with e3/3 and 45 with e2/2 or e3/2 genotypes were recruited. All subjects were unrelated elderly type 2 diabetic patients with ischaemia electrocardiographic change, aged 60-87 years, and their cardiac function were all the class I stage at their time of enrollment. A follow-up study of 3-10 years was undergone. The results are as follows: At baseline, serum total cholesterol and low-density lipoprotein (LDL) cholesterol concentrations were higher in subjects with e4/3 or e4/4 than in subjects with e2/2 or e3/2 (p<0.05). Lipoprotein(a) concentration was lower in subjects with e2/2 or e3/2 than in subjects with e3/3 and e4/3 or e4/4 (p < 0.05). During the 3-10 years follow-up period, a total of 55 patients who died from CAD were recorded in this sample. Compared with patients with e3/3 (p = 0.024) and patients with e2/2 or e2/3 genotypes (p = 0.002), the mortality rate of CAD in patients with e4/3 or e4/4 genotypes was the highest (47.8%). Stepwise discriminant analysis revealed that in the diabetic population studied Apo e4 allele was independently and significantly associated with CAD death (B = 0.65). However, the strength of the association decreased (B = 0.44) when total cholesterol, LDL-cholesterol and lipoprotein(a) were included in the model. Therefore, we concluded that Apo e4 allele increases the risk of CAD death in elderly type 2 diabetes mellitus with ischaemia electrocardiographic change.