Evaluation of transcriptional levels of the natriuretic peptides, endothelin-1, adrenomedullin, their receptors and long non-coding RNAs in rat cardiac tissue as cardiovascular biomarkers of aging

Ibrutinib facilitates the sensitivity of colorectal cancer cells to ferroptosis through BTK/NRF2 pathway

Ibrutinib is a drug that inhibits the protein Burton's tyrosine kinase and thereby the nuclear translocation of Nrf2, which played a key role in mediating the activation of antioxidants during stress conditions and ferroptosis resistance. This study aimed to identify the effect of Ibrutinib and ferroptosis inducer on colorectal cancer (CRC) treatment and its underlying mechanism. In our study, we found the upregulation of Nrf2 was correlated with CRC progression and antioxidant proteins. Ibrutinib sensitized CRC to ferroptosis inducers, suggested by further reduced CRC cell viability, proliferation and decreased antioxidant protein levels in CRC cells after combination treatment of Ibrutinib and RSL3 or Ibrutinib and Erastin both in vivo and in vitro. Knockout of Nrf2 diminished the regulatory effect of Ibrutinib on CRC sensitivity to ferroptosis inducers. Altogether, this study demonstrated that Ibrutinib increases the sensitivity of CRC cell to ferroptosis inducers by inhibiting Nrf2.

Inter-tissue communication of mitochondrial stress and metabolic health

Mitochondria function as a hub of the cellular metabolic network. Mitochondrial stress is closely associated with aging and a variety of diseases, including neurodegeneration and cancer. Cells autonomously elicit specific stress responses to cope with mitochondrial stress to maintain mitochondrial homeostasis. Interestingly, mitochondrial stress responses may also be induced in a non-autonomous manner in cells or tissues that are not directly experiencing such stress. Such non-autonomous mitochondrial stress responses are mediated by secreted molecules called mitokines. Due to their significant translational potential in improving human metabolic health, there has been a surge in mitokine-focused research. In this review, we summarize the findings regarding inter-tissue communication of mitochondrial stress in animal models. In addition, we discuss the possibility of mitokine-mediated intercellular mitochondrial communication originating from bacterial quorum sensing.

Transcriptional level evaluation of osteopontin/miRNA-181a axis in hepatocellular carcinoma cell line-secreted extracellular vesicles

Recent evidence suggested the role of secreted extracellular vesicles (EVs) in the intracellular signalling within the liver becoming a promising candidate as biomarker in hepatocellular carcinoma (HCC). Osteopontin (OPN) seems to play a relevant role both for early diagnosis of HCC than on the mechanisms that drive oncogenesis but, to date, information on the expression levels of OPN in EVs secreted by HCC tumor cell line are missing. The study aimed to verify, by transcriptional and proteomic study, the presence of OPN in EVs secreted by tumorigenic (HepG2) and non-tumorigenic hepatocyte cell line (WRL68), and to analyse the expression variations of OPN, its isoforms and miRNA-181a in both these EVs. "In silico analysis" was also performed via the Gene expression Profiling Interactive analysis (GEPIA) and Hepatocellular Carcinoma Database (HCCDB). An up-regulation of OPN in EVs secreted by HepG2 with respect to WRL68 was found in line with the results obtained by the "in silico analysis". The study demonstrates, for the first time, the OPN isoforms and its modulator miRNA-181a expression in EVs secreted by both cell lines, highlighting high levels of OPN isoforms in EVs secreted by HepG2 and identifying OPN as a promising biomarker for HCC diagnosis.

Connexin Expression in Human Minor Salivary Glands: An Immunohistochemical Microscopy Study

Connexins (Cxs) are transmembrane proteins involved in the formation of hemichannels and gap junctions (GJs). GJs are involved in various physiological functions, including secretion in glandular tissue. It has been demonstrated that Cx26, Cx32, and Cx43 are mainly expressed in glands, but no data are available in human salivary glands to date. The aim of our study was to investigate the presence and the localization of Cxs in human minor labial salivary glands. Immunofluorescence and immunoelectron microscopy were employed to evaluate the Cx26, Cx32, and Cx43 protein in human labial salivary gland biopsies (hLSGBs). RT-PCR was also used to detect their mRNA expression. Cx expression was found at both the mRNA and protein levels in all hLSGBs analysed. Cxs were observed at the level of the duct and acinar cells, as well as in myoepithelial cells. The localization of the three Cx types was very similar, suggesting colocalization of these Cxs in the same connexons. These results demonstrated the presence of Cxs in human salivary glands for the first time. Moreover, the few samples with primary Sjögren’s Syndrome analysed only by immunofluorescence showed an alteration of the Cx expression, indicating that these proteins could be involved in salivary gland dysfunctions.

miRNA and long non-coding RNA transcriptional expression in hepatocellular carcinoma cell line-secreted extracellular vesicles

Extracellular vesicles (EVs) are membrane-released vesicles acting as transporters of proteins, lipids and short/long non-coding RNA (miRNAs and lncRNAs). They are released by normal and pathological cells, including hepatocellular carcinoma (HCC). To date, studies focused on miRNAs and lncRNAs contained in EVs derived from HCC are limited. Our aim was to analyze the transcriptional profile of potential regulating miRNAs and lncRNAs in EVs secreted by HCC tumor cell line (HepG2, n = 6), and from a non-tumorigenic hepatocyte cell line (WRL68, n = 6), to compare their differential expression profile and to identify novel molecular diagnostic markers of HCC. EVs were isolated from the conditioned medium, through differential centrifugations. The expression profile of miRNAs (miR-23a, miR-16-2, miR-181a, miR-373, miR-205, miR-27a, miR-1323, and miR-532) and lncRNAs (HULC, HOTAIR, XIST, MALAT-1, GAS-5, H19) was performed in Real-time PCR, and their transcript was found both in HepG2 and WRL68 EVs. Lower miR-181a, miR-205 and miR-1323 expression were detected in EVs secreted by HepG2 compared to WRL68, while an opposite trend was observed for miR-23a, miR-16-2, miR-373, miR-27a, and miR-532. Several significant correlations were found between miRNA and lncRNA. An in silico analysis was also performed. The results obtained could identified them as new potential diagnostic and prognostic biomarkers of HCC.

Heart and liver connexin expression related to the first stage of aging: A study on naturally aged animals

Connexins are membrane-spanning proteins that form membrane channels and hemichannels. They are involved in the cellular communication and in the maintenance of tissue homeostasis. Recent studies in humans and animals have demonstrated that the expression and distribution of Cx43, the most studied connexin, can change during aging. However, the research on the involvement of the other connexins in cardiac and hepatic aging is, at present, still very poor. Hence, the aim of this study is to evaluate the expression of Cx43 and Cx26 in the heart as well as Cx26 and Cx32 in the liver of a rat model that aged naturally, rather than prematurely because of genetic mutations or age-related diseases. The results obtained in the present study have demonstrated that these connexins decrease in rat cardiomyocytes and in rat hepatocytes as they age. This change was revealed only at protein level, as connexin-mRNAs remained unchanged during aging. Moreover, the aged rats showed an increase in body fat, whose subcutaneous layer tended to be higher. Finally, how these changes could represent signs of physiological adaptation in successful aging was discussed.