Mitigating cognitive impairment in aging mice: Exploring the therapeutic potential of ischelium.

To deeply explore the intervention effects of ischelium on the cognitive memory decline in naturally aging mice and its potential mechanisms, we randomly divided mice into four groups: young control group (C), elderly group (M), ischelium low-dose group (L), and ischelium high-dose group (H). The experiment lasted for 12 weeks. We employed the Y-maze test, open field test, and conditioned fear test to evaluate the memory functions of each group. Through HE staining and electron microscopy, we observed morphological changes in the mouse hippocampus. RT-PCR was used to detect changes in the expression of factors related to cognitive function in the hippocampus of elderly mice. We analyzed the changes in the Nrf2/HO-1 pathway and the inflammatory factors IL-1ß and TNF-α using elisa. Additionally, we examined the enzymatic activities of SOD, CAT, GSH-Px, and MDA in the hippocampus and analyzed the compositional changes of gut microbiota in mice using 16S technology. Our results indicate that ischelium effectively ameliorates cognitive impairments in elderly mice.

Molecular characteristics and immune function of ubiquitin C-terminal hydrolase-L3 in Macrobrachium nipponense.

Ubiquitin C-terminal hydrolase-L3 (UCHL3) is a deubiquitinating enzyme involved in the repair mechanism of homologous recombinations of DNA double strand breaks (DBS). However, the role of UCHL3 in crustacean immune regulation has not been studied. In this experiment, we cloned and analyzed the expression profile of the UCHL3 gene from Macrobrachium nipponense (MnUCHL3). The obtained full-length cDNA of the MnUCHL3 transcript was 1192 bp, and it had a 687 bp open reading frame encoding a 228 amino acid protein, and the structure of UCHL3 is highly similar to that of other invertebrates. Real-time PCR results indicated that MnUCHL3 was expressed in all detected tissues, with the highest expression levels in the hepatopancreas, and the expression of MnUCHL3 in the gill and hepatopancreas was downregulated to different degrees within 48 h after the infection of viruses and bacteria. Furthermore, knockdown of MnUCHL3 expression by double-stranded RNA (dsRNA) injection in Aeromonas hydrophila-infected prawns increased prawn mortality and bacterial growth. In addition, overexpression of MnUCHL3 in HEK293T cells in vitro suggested that MnUCHL3 could activate the NF-κB signal path and the expression levels of NF-κB signaling cascade members and AMPs, exhibiting remarkable downregulation in the MnUCHL3-silenced group. The above experimental conclusions revealed that UCHL3 gene might be involved in the innate immune response to bacterial infection by regulating the synthesis of a series of AMPs, and these results might provide new insights into UCHL3 in invertebrates.

The novel six LIM and one PET domain-containing protein Lmpt is involved in the immune response through activation of the NF-κB signalling pathway in the crustacean, Macrobrachium nipponense.

The four-and-a-half LIM-only protein family of transcription co-factors participates in various cellular processes, such as cell proliferation, cell differentiation, apoptosis, cell adhesion, migration, transcription and signal transduction. However, the knowledge of the structural characteristics and immune functions of its ancestor Lmpt, which contains six LIM domains at the C-terminus and a PET domain at the N-terminus, is limited in invertebrates, especially in crustaceans. In the present study, a novel Lmpt from oriental river prawn (Macrobrachium nipponense) was identified, and its role in the immune response was investigated. Its full-length cDNA sequence was 6407 bp, which contained a 2595 bp ORF encoding 865 amino acids, exhibiting high similarity to the structure of Lmpt derived from other invertebrates. Tissue distribution analysis revealed that MnLmpt was widely expressed in all examined tissues, and high expression levels were observed in muscle, heart and intestine in M. nipponense. After experimental challenges with bacteria and virus, the transcription levels of MnLmpt significantly fluctuated in gill and hepatopancreas, indicating that it might play a role in the innate immune response in M. nipponense. Silencing of MnLmpt by dsRNA injection in vivo could promote bacterial growth, suggesting that MnLmpt exerted an antibacterial immune function in prawn. Immunocytochemistry assay results demonstrated that MnLmpt was able to translocate from the cytoplasm to the nucleus after being stimulated with pathogens. The expression levels of NF-κB signalling cascade members, such as dorsal, relish, TAK1, TAB1, Ikkß, and Ikkε, and AMPs, including ALF4, Cru1, and Cru2, exhibited significant downregulation in the MnLmpt silenced group. Similarly, dual-luciferase reporter assays also demonstrated that MnLmpt could stimulate an NF-κB signalling cascade. Meanwhile, all of the LIM domains of MnLmpt could trigger NF-κB signalling; however, their cumulative effect on NF-κB promoter activation was hardly observed. These results showed that MnLmpt might play a crucial role in the innate immune response in M. nipponense, and these findings paved the way for a better understanding of the immune system in crustacean species.

The potential role of PSMA6 in modulating fat deposition in pigs by promoting preadipocyte proliferation and differentiation.

To investigate whether the proteasome subunit alpha 6 (PSMA6) gene has an effect on fat deposition, the gene expression profile was first detected in Berkshire pigs and Jinhua pigs (JHP). The results demonstrated that significantly higher levels of mRNA expression were identified in adipose tissues and the liver. Interestingly, when compared to the longissimus dorsi muscle (LDM) in each breed, it was discovered that the expression levels of the PSMA6 gene in these tissues of JHP were considerably higher than those in Berkshire pigs. Meantime, some significant correlations of PSMA6 mRNA expression in lipid metabolism-related tissues such as the liver and LDM with the marbling score, as well as the content of intramuscular fat (IMF), in pigs were found by correlation coefficient analysis. To further explore the effects of PSMA6 expression on fat deposition, we performed PSMA6 overexpression in 3T3-L1 cells via Lentivirus infection. Our results indicated that PSMA6 could promote cell proliferation and accelerate cell division. It was also found that the transcription factors CCAAT/enhancer-binding protein alpha (CEBPA) and peroxisome proliferator-activated receptor gamma (PPARG), as well as the key genes related to adipogenesis, were upregulated, while the genes related to fat oxidation were significantly downregulated, which indicated that the PSMA6 gene could stimulate the differentiation of preadipocytes.

Characterization and immune function of decapentaplegic (Dpp) gene from the oriental river prawn, Macrobrachium nipponense.

The Decapentaplegic (Dpp) gene, which belongs to the TGF-ß superfamily, is involved in multiple developmental processes in eukaryotic species. In this study, we firstly identified and characterized Dpp from Macrobrachium nipponense. Its full-length open reading frame (ORF) cDNA was 1332 bp, encoding 443 amino acids. The putative MnDpp protein contained a signal peptide, a TGF-ß propeptide region and a TGF-ß domain. Its TGF-ß domain was highly conserved from vertebrates to invertebrates, and exhibited highly similarity to Dpp derived from Bombyx mori. qRT-PCR analysis suggested that MnDpp expressed in all tested tissues and responded to both bacterial and virus pathogens, indicating MnDpp was involved in the innate immune response of M. nipponense. Knockdown of MnDppin vivo significantly increased bacteria growth and markedly decreased the expressions of NF-κB signaling genes including dorsal, relish, TAK1, TAB1, Ikkß and Ikkε as well as antimicrobial peptides (AMPs) including ALF2, ALF3, ALF4, ALF5, Cru1 and Cru2. Moreover, in vitro overexpression of MnDpp protein in HEK293T cells further demonstrated that it exerted antibacterial immune response by activation of NF-κB signaling cascade. In summary, these results indicated that MnDpp played an important role in the innate immunity in M. nipponense by modulating NF-κB signaling pathway, which might provide new insights about Dpp in crustaceans and paved the way for a better understanding of the crustacean innate immune system.

A novel SNW/SKIP domain-containing protein, Bx42, is involved in the antibacterial responses of Macrobrachium nipponense.

Bx42, the homologue of SNW1 in mammals, is involved in pre-mRNA splicing and transcriptional regulation. However, the presence and function of Bx42 have remained poorly understood in invertebrates until now. In the current study, a novel SNW domain-containing protein (MnBx42) from Macrobrachium nipponense was identified, and its potential role in the immune response was investigated. The full-length MnBx42 was 7467 bp with an open reading frame of 1653 bp, encoding 550 amino acids. Real-time PCR analysis suggested that MnBx42 was predominantly expressed in the intestine, gills and hepatopancreas, and immunofluorescence assays indicated that it was located in the nucleus. Its expression level was significantly decreased in M. nipponense post-challenge with white spot syndrome virus (WSSV) as well as Aeromonas hydrophila and Staphylococcus aureus, implying its participation in the innate immune response. The knockdown of MnBx42 in vivo notably increased the susceptibility of the prawns to bacterial infection, markedly increased the bacterial load in the gills, and significantly attenuated the phagocytic activity of haemocytes. Dual-luciferase reporter assays illustrated that MnBx42 could activate the NF-κB pathway. Consistent with this, when MnBx42 was silenced in vivo, the expression levels of antimicrobial peptides (AMPs), including ALF2, ALF3, ALF4, ALF5, Cru1 and Cru2, and NF-κB signalling genes, including dorsal, relish, TAK1, TAB1, Ikkß, and Ikkε, were significantly reduced. Taken together, these findings may provide new insights about Bx42 in crustaceans and pave the way for a better understanding of the crustacean innate immune system.