Systemic administration of dorsomorphin relieves inflammatory nociception in the mouse formalin test.

Inflammatory pain is the most important clinical symptom of inflammatory diseases. Despite intensive research into inflammatory pain mechanisms, the majority of analgesics available are based on mechanistic classes of compounds that have been known for many years, as a result, inflammatory pain control remains a challenge for drug design in the context of clinically unmet needs in terms of safety and efficacy. A growing literature supports that pro-inflammatory cytokine signaling plays a crucial role in the development of inflammatory pain. Modulation of the pro-inflammatory cytokine may hold the key to improved pain management. Previous studies have reported that dorsomorphin played key roles in inflammation. But the role of dorsomorphin in the formalin-induced inflammatory nociception in mice has never been reported. Here, we report a new function of dorsomorphin which can inhibit formalin-induced inflammatory nociception in mice. The antinociceptive effect of dorsomorphin mainly depended on inhibiting the p38 MAPK/c-fos signaling and regulating inflammatory mediators.

Micropeptides Identified from Human Genomes.

Advanced analytic techniques, such as ribosome profiling and mass spectrometry, as well as improved bioinformatics technology, have promoted the field of genome annotation forward and have identified thousands of likely coding short open reading frames (sORFs) in the human genome. The discovery of sORFs and their products allows us to realize that the complexity of the human genome is far greater than previously assumed. Here, we provide a review of human micropeptides encoded by various transcripts such as mitochondrial rRNAs, long noncoding RNAs, circular RNAs, upstream of mRNAs, and so on.

Protective effect of MOTS-c on acute lung injury induced by lipopolysaccharide in mice.

MOTS-c (mitochondrial open-reading-frame of the twelve S rRNA-c), a mitochondrial-derived 16-amino acid peptide, targets the methionine-folate cycle, increases 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) levels, and eventually activates AMP-activated protein kinase (AMPK). AMPK activation can attenuate neutrophil pro-inflammatory activity and attenuates lipoteichoic acid (LTA) and lipopolysaccharide (LPS) induced acute lung injury (ALI) in mice. However, to our knowledge, the role of MOTS-c in LPS-induced ALI remains unclear. Hence, we investigated the potential effectiveness and underlying mechanism of MOTS-c against LPS-induced ALI in mice. The intraperitoneal administration of MOTS-c (5 mg/kg, i.p., bid, 6 days) before intratracheal LPS instillation attenuated body weight loss and pulmonary edema, inhibited neutrophilic tissue infiltration in lung tissue, downregulated the expression of cytokine-induced neutrophil chemoattractant-1 (CINC-1) and intercellular cell adhesion molecule-1 (ICAM-1) in lung tissues, decreased the levels of TNF-α, IL-1ß, and IL-6, and increased the expression of IL-10 and SOD in serum, lung tissue, and bronchoalvelolar lavage fluid (BALF). Moreover, MOTS-c treatment significantly promoted p-AMPKα and SIRT1 expression and suppressed LPS-induced ERK, JNK, p38, p65, and STAT3 activation in the mouse lung tissues. Collectively, these findings suggest that MOTS-c plays important roles in protecting the lungs from the inflammatory effects of LPS-induced ALI. The effects of MOTS-c are probably orchestrated by activating AMPK and SIRT1, inhibiting ERK, JNK, p65, and STAT3 signaling pathways. Thus, MOTS-c appears to be a novel and promising candidate for the treatment of ALI.