Current Protein and Peptide Science - Volume 23, Issue 6, 2022

MicroRNAs (MiRNAs) are endogenous non-coding small RNA molecules that regulate gene expression in plants, animals and some viruses. Both normal and pathological liver processes are regulated by miRNAs. Recent research indicated that miRNAs have been implicated in liver diseases caused by viral hepatitis (Hepatitis B and Hepatitis C), metabolic problems, alcohol and drug abuse. Because altered miRNA expression is linked to liver metabolic dysregulation, liver damage, liver fibrosis, and tumour growth, miRNAs are promising therapeutic targets for the detection and treatment of liver diseases. In this review, we summarise the current knowledge about the role of microRNAs in acute and chronic liver diseases, including hepatocellular carcinoma. We cover the miRNA-based therapy for liver disorders as well as the use of miRNAs as biomarkers for early diagnosis, prognosis and assessment of liver diseases. The investigation of miRNAs in liver diseases will provide a better understanding of the pathogeneses, identification of biomarkers and therapeutic targets for liver diseases in the future.

Myelin Oligodendrocyte Glycoprotein-antibody disease (MOGAD) is an immune-mediated disorder that mainly targets the central nervous system of the patient. The pattern of inflammation caused by MOGAD mainly targets the brain stem, spinal cord, and optic nerve, and the symptoms vary from person to person. Its clinical features often overlap with Multiple Sclerosis (MS) and Neuromyelitis Optica Spectrum Disorder (NMOSD) which makes the accurate diagnosis of this rare neurodegenerative disease quite difficult. Hence, this review was attempted not only to understand MOGAD but also to comprehend the differences between MOGAD and MS with the help of a brief overview of the similarities and contrasting features. Here we highlight the mechanism and importance of MOG in myelination and demyelination. Glycosylation has a serious impact on the myelination of neurons as N-glycan helps in the proper folding of MOG. On transforming into an autoantigen, MOG can activate the classical complement pathway by triggering the activation of proteins associated with the complement cascade. Patients with persistently positive antibodies to MOG are at risk for recurrent episodes of MOGAD. In the current scenario, there is an urgent need to develop therapeutic interventions that induce remyelination. Remyelination in terms of MOG glycosylation is hypothesized as a possible strategy to treat patients diagnosed with MOGAD. On the whole, the article aims to provide a clear insight into the disease and the structural aspects associated with it.

With the development of tissue engineering research, biological scaffolds have been widely studied and applied in the field of regenerative medicine. Self-assembling nanopeptide hydrogels have good biocompatibility, and their seed cells can be used for their biological activities and have no toxic side effects. The products can be absorbed and degraded by the organism and have great advantages in tissue engineering and regenerative medicine. Studies have shown that the self-assembled nano peptide hydrogel and adipose-derived mesenchymal stem cells (ADMSCs) mixed solution are "biological ink". 3D related biological printing technology can be used to print related tissue models and induce ADMSCs to differentiate into blood vessels. It is further illustrated that the use of self-assembled nano peptide hydrogel scaffolds to load stem cells has a good application prospect in stem cell transplantation and 3D biological printing.

Aim: Laccases and peroxidases have attracted great interest for industrial and environmental applications. These enzymes have a broad substrate range and a robust oxidizing ability. Moreover, using mediators or co-oxidants makes it possible to increase their catalytic activity and extend their substrate scope to more resistant chemical structures. Background: Fungal laccases and ligninolytic peroxidases, mainly lignin and manganese peroxidases, are the privileged oxidoreductases for bioremediation processes. Nonetheless, an increasing diversity of laccases and peroxidase-type enzymes has been proposed for environmental technologies. Objective: This article aims to provide an overview of these enzymes and compare their applicability in the degradation of organic pollutants. Methods: Fundamental properties of the proteins are covered and applications towards polycyclic aromatic hydrocarbons (PAHs) and pesticides are specially focused. Results: Laccases are multicopper oxidases initially studied for applications in the pulp and paper industry but able to oxidize a variety of environmentally concerning compounds. Relying on O2, laccases do not require peroxides nor auxiliary agents, like Mn²⁺, although suitable redox mediators are needed to attack the more recalcitrant pollutants (e.g., PAHs). True and pseudo-peroxidases use a stronger oxidant (H2O2) and the redox chemistry at the heme site generates high potential species that allow the oxidation of dyes and some pesticides. Conclusion: Lately, research efforts have been directed to enzyme discovery, testing with micropollutants, and improving biocatalysts’ stability by immobilization and protein engineering. Further understanding of the effects of natural media components and solvents on the enzymes might lead to competitive enzymatic treatments of highly toxic media.

Background: Hypopharyngeal squamous cell carcinoma (HSCC) is a common malignant cancer characterized by high metastasis and infiltration. The development of new approaches for the early diagnosis and identification of new therapeutic targets is essential. TIPE2 is well known as a tumor suppressor and related to a favorable prognosis of HSCC. However, its underlying mechanism remains unclear. Methods and Materials: TIPE2 expression was determined by immunohistochemistry and RT-qPCR. A TIPE2 overexpression stable cell line was generated by lentivirus infection. TIPE2 and other related protein levels were detected by western blotting. The cell cycle and apoptosis were performed by flow cytometric analysis. Cell proliferation was measured with a Cell Counting Kit-8 (CCK-8) assay, and the activity of caspase-3 and caspase-7 was assessed by Caspase-Glo® 3/7 Assay. All data were analyzed with SPSS 25 and GraphPad Prism 8.0. Results: TIPE2 expression was significantly down-regulated in HSCC. Low TIPE2 expression may be associated with poor prognosis in HSCC. TIPE2 overexpression markedly inhibited tumor cell migration. Moreover, TIPE2 decreased cell proliferation but promoted apoptosis. TIPE2 suppressed tumor growth by activating Epithelial-Mesenchymal Transition (EMT) and the extrinsic apoptosis pathway. Conclusion: TIPE2 inhibited tumor progression by suppressing cell migration but promoting apoptosis. TIPE2 can be a new therapeutic target in HSCC.