Milk Exosomal miR-27b Worsen Endoplasmic Reticulum Stress Mediated Colorectal Cancer Cell Death

SGLT2 inhibitor promotes mitochondrial dysfunction and ER-phagy in colorectal cancer cells

BACKGROUND

Sodium-glucose transporter 2 (SGLT2) inhibitors (iSGLT2) are approved medications for type 2 diabetes. Recent studies indicate that iSGLT2 inhibit the growth of some cancer cells. However, the mechanism(s) remains to be fully elucidated.

METHODS

The SGLT2 levels were determined in normal colon CCD 841 CoN and, HCT 116, HT-29, SW480 and LoVo colorectal cancer (CRC) cell lines by quantitative real-time PCR and western blot. The effect of iSGLT2 canagliflozin on cell proliferation was examined using CCK-8, as its role on CRC cells metabolism and tumorigenesis has been evaluated by XF HS Seahorse Bioanalyzer and flow cytometric analyses. Transient gene silencing experiments and analysis of protein-protein interaction network were conducted to evaluate the SGLT2 molecular targets in CRC cells.

RESULTS

Data showed that the treatment with iSGLT2 (50 µM) for 72 h induced cell cycle arrest (p < 0.001), impaired glucose and energetic metabolism (p < 0.001), promoted apoptotic cell death and ER stress flowing into autophagy (p < 0.001) in HCT 116 and HT-29 cells. These cellular events were accompanied by sirtuin 3 (SIRT3) upregulation (p < 0.01), as also supported by SIRT3 transient silencing experiments resulting in the attenuation of the effects of iSGLT2 on the cellular metabolic/energetic alterations and the induction of programmed cell death. The identification and validation of dipeptidyl peptidase 4 (DPP4) as potential common target of SGLT2 and SIRT3 were also assessed.

CONCLUSIONS

These results deepened knowledge on the iSGLT2 contribution in limiting CRC tumorigenesis unveiling the SGLT2/SIRT3 axis in the cytotoxic mechanisms.

MiR-148a-3p/SIRT7 Axis Relieves Inflammatory-Induced Endothelial Dysfunction

In endothelial cells, miR-148a-3p is involved in several pathological pathways, including chronic inflammatory conditions. However, the molecular mechanism of miR-148a-3p in endothelial inflammatory states is, to date, not fully elucidated. To this end, we investigated the involvement of miR-148a-3p in mitochondrial dysfunction and cell death pathways in human aortic endothelial cells (teloHAECs) treated with interleukin-6 (IL-6), a major driver of vascular dysfunction. The results showed that during IL6-activated inflammatory pathways, including increased protein levels of sirtuin 7 (SIRT7) (p < 0.01), mitochondrial stress (p < 0.001), and apoptosis (p < 0.01), a decreased expression of miR-148a-3p was observed (p < 0.01). The employment of a miR-148a mimic counteracted the IL-6-induced cytokine release (p < 0.01) and apoptotic cell death (p < 0.01), and ameliorated mitochondria redox homeostasis and respiration (p < 0.01). The targeted relationship between miR-148a-3p and SIRT7 was predicted by a bioinformatics database analysis and validated via the dual-luciferase reporter assay. Mechanistically, miR-148a-3p targets the 3' untranslated regions of SIRT7 mRNA, downregulating its expression (p < 0.01). Herein, these in vitro results support the role of the miR-148a-3p/SIRT7 axis in counteracting mitochondrial damage and apoptosis during endothelial inflammation, unveiling a novel target for future strategies to prevent endothelial dysfunction.

Milk-derived exosome nanovesicles: recent progress and daunting hurdles

Raw milk is the foundation of quality and safety in the dairy industry, and improving milk source management is the fundamental guarantee. Milk-derived exosomes (MDEs) are nanoscale information transfer molecules secreted by mammary cells with unique content and high stability, which can be used not only as potential markers to analyze key traits of lactation, reproduction, nutrition and health of animals, but also help farm managers to take timely interventions to improve animal welfare, milk quality, and functional traits. Our review first outlines the latest advances in MDEs isolation and purification, compositional analysis and characterization tools. We then provide a comprehensive summary of recent applications of MDEs liquid biopsy in breed selection, disease prevention and control, and feeding management. Finally, we evaluate the impact of processing on the stability of MDEs to offer guidance for dairy production and storage. The limitations and challenges in the development and use of MDEs markers are also discussed. As a noninvasive marker with high sensitivity and specificity, the MDEs-mediated assay technology is expected to be a powerful tool for measuring cow health and raw milk quality, enabling dynamic and precise regulation of dairy cows and full traceability of raw milk.

Metabolic Alteration Bridging the Prediabetic State and Colorectal Cancer

Prediabetes and colorectal cancer (CRC) represent compelling health burdens responsible for high mortality and morbidity rates, sharing several modifiable risk factors. It has been hypothesized that metabolic abnormalities linking prediabetes and CRC are hyperglycemia, hyperinsulinemia, and adipokines imbalance. The chronic stimulation related to these metabolic signatures can favor CRC onset and development, as well as negatively influence CRC prognosis. To date, the growing burden of prediabetes and CRC has generated a global interest in defining their epidemiological and molecular relationships. Therefore, a deeper knowledge of the metabolic impairment determinants is compelling to identify the pathological mechanisms promoting the onset of prediabetes and CRC. In this scenario, this review aims to provide a comprehensive overview on the metabolic alterations of prediabetes and CRC as well as an overview of recent preventive and therapeutic approaches for both diseases, focusing on the role of the metabolic state as a pivotal contributor to consider for the development of future preventive and therapeutic strategies.

α-Lipoic acid alleviates dextran sulfate sodium salt-induced ulcerative colitis via modulating the Keap1-Nrf2 signaling pathway and inhibiting ferroptosis

BACKGROUND

Inflammatory bowel disease (IBD) is a chronically relapsing inflammatory disease with severe diarrhea, fatigue and weight loss. α-Lipoic acid (LA), a well-known antioxidant, is able to scavenge reactive oxygen species (ROS) and maintain a healthy cellular redox state. However, the role of LA in protecting IBD is still unclear. Hence the aim of this research was to investigate the protective effect of LA on dextran sulfate sodium salt-induced ulcerative colitis (UC) and its underlying mechanism.

RESULTS

Here, our findings showed that LA significantly alleviated UC symptoms and the overproduction of pro-inflammatory cytokines in UC mice. In addition, LA treatment inhibited intestinal cell apoptosis by regulating the expression levels of p53/caspase-3 pathway-related protein in UC mice. Meanwhile, the inhibitory effects of LA on colonic oxidative stress and ferroptosis were revealed. Our study further demonstrated that LA treatment could regulate the Kelch-like ECH-associating protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway. Interestingly, we confirmed that LA inhibited ferroptosis by attenuating endoplasmic reticulum stress and suppressing apoptosis in erastin-induced ferroptosis model in vitro.

CONCLUSION

Taken together, this study's findings suggest that LA could be considered as a therapeutic agent protecting against IBD. © 2023 Society of Chemical Industry.

Dietary Epigenetic Modulators: Unravelling the Still-Controversial Benefits of miRNAs in Nutrition and Disease

In the context of nutrient-driven epigenetic alterations, food-derived miRNAs can be absorbed into the circulatory system and organs of recipients, especially humans, and potentially contribute to modulating health and diseases. Evidence suggests that food uptake, by carrying exogenous miRNAs (xenomiRNAs), regulates the individual miRNA profile, modifying the redox homeostasis and inflammatory conditions underlying pathological processes, such as type 2 diabetes mellitus, insulin resistance, metabolic syndrome, and cancer. The capacity of diet to control miRNA levels and the comprehension of the unique characteristics of dietary miRNAs in terms of gene expression regulation show important perspectives as a strategy to control disease susceptibility via epigenetic modifications and refine the clinical outcomes. However, the absorption, stability, availability, and epigenetic roles of dietary miRNAs are intriguing and currently the subject of intense debate; additionally, there is restricted knowledge of their physiological and potential side effects. Within this framework, we provided up-to-date and comprehensive knowledge on dietary miRNAs' potential, discussing the latest advances and controversial issues related to the role of miRNAs in human health and disease as modulators of chronic syndromes.

Small RNA-big impact: exosomal miRNAs in mitochondrial dysfunction in various diseases

Mitochondria are multitasking organelles involved in maintaining the cell homoeostasis. Beyond its well-established role in cellular bioenergetics, mitochondria also function as signal organelles to propagate various cellular outcomes. However, mitochondria have a self-destructive arsenal of factors driving the development of diseases caused by mitochondrial dysfunction. Extracellular vesicles (EVs), a heterogeneous group of membranous nano-sized vesicles, are present in a variety of bodily fluids. EVs serve as mediators for intercellular interaction. Exosomes are a class of small EVs (30-100 nm) released by most cells. Exosomes carry various cargo including microRNAs (miRNAs), a class of short noncoding RNAs. Recent studies have closely associated exosomal miRNAs with various human diseases, including diseases caused by mitochondrial dysfunction, which are a group of complex multifactorial diseases and have not been comprehensively described. In this review, we first briefly introduce the characteristics of EVs. Then, we focus on possible mechanisms regarding exosome-mitochondria interaction through integrating signalling networks. Moreover, we summarize recent advances in the knowledge of the role of exosomal miRNAs in various diseases, describing how mitochondria are changed in disease status. Finally, we propose future research directions to provide a novel therapeutic strategy that could slow the disease progress mediated by mitochondrial dysfunction.

Potential therapeutic effects of milk-derived exosomes on intestinal diseases

Exosomes are extracellular vesicles with the diameter of 30 ~ 150 nm, and are widely involved in intercellular communication, disease diagnosis and drug delivery carriers for targeted disease therapy. Therapeutic application of exosomes as drug carriers is limited due to the lack of sources and methods for obtaining adequate exosomes. Milk contains abundant exosomes, several studies have shown that milk-derived exosomes play crucial roles in preventing and treating intestinal diseases. In this review, we summarized the biogenesis, secretion and structure, current novel methods used for the extraction and identification of exosomes, as well as discussed the role of milk-derived exosomes in treating intestinal diseases, such as inflammatory bowel disease, necrotizing enterocolitis, colorectal cancer, and intestinal ischemia and reperfusion injury by regulating intestinal immune homeostasis, restoring gut microbiota composition and improving intestinal structure and integrity, alleviating conditions such as oxidative stress, cell apoptosis and inflammation, and reducing mitochondrial reactive oxygen species (ROS) and lysosome accumulation in both humans and animals. In addition, we discussed future prospects for the standardization of milk exosome production platform to obtain higher concentration and purity, and complete exosomes derived from milk. Several in vivo clinical studies are needed to establish milk-derived exosomes as an effective and efficient drug delivery system, and promote its application in the treatment of various diseases in both humans and animals.

Application of Milk Exosomes for Musculoskeletal Health: Talking Points in Recent Outcomes

Milk is a nutrient-rich food source, and among the various milks, breast milk is a nutrient source provided by mothers to newborns in many mammals. Exosomes are nano-sized membranous extracellular vesicles that play important roles in cell-to-cell communication. Exosomes originate from endogenous synthesis and dietary sources such as milk. Discovered through electron microscopy as floating vesicles, the existence of exosomes in human milk was confirmed owing to a density between 1.10 and 1.18 g/mL in a sucrose gradient corresponding to the known density of exosomes and detection of MHC classes I and II, CD63, CD81, and CD86 on the vesicles. To date, milk exosomes have been used for treating many diseases, including cancers, and are widely proposed as promising carriers for the delivery of chemotherapeutic agents. However, few studies on milk exosomes focus on geriatric health, especially sarcopenia and osteoporosis related to bone and muscle. Therefore, the present study focused on milk exosomes and their cargoes, which are potential candidates for dietary supplements, and when combined with drugs, they can be effective in treating musculoskeletal diseases. In this review, we introduce the basic concepts, including the definition, various sources, and cargoes of milk exosomes, and exosome isolation and characterization methods. Additionally, we review recent literature on the musculoskeletal system and milk exosomes. Since inflammation and oxidative stress underly musculoskeletal disorders, studies reporting the antioxidant and anti-inflammatory properties of milk exosomes are also summarized. Finally, the therapeutic potential of milk exosomes in targeting muscle and bone health is proposed.

Recent insights into the nutritional immunomodulation of cancer-related microRNAs

Cancer is the most common cause of death worldwide, following cardiovascular diseases. Cancer is a multifactorial disease and many reasons such as physical, chemical, biological, and lifestyle-related factors. Nutrition, which is one of the various factors that play a role in the prevention, development, and treatment of many types of cancer, affects the immune system, which is characterized by disproportionate pro-inflammatory signaling in cancer. Studies investigating the molecular mechanisms of this effect have shown that foods rich in bioactive compounds, such as green tea, olive oil, turmeric, and soybean play a significant role in positively changing the expression of miRNAs involved in the regulation of genes associated with oncogenic/tumor-suppressing pathways. In addition to these foods, some diet models may change the expression of specific cancer-related miRNAs in different ways. While Mediterranean diet has been associated with anticancer effects, a high-fat diet, and a methyl-restricted diet are considered to have negative effects. This review aims to discuss the effects of specific foods called "immune foods," diet models, and bioactive components on cancer by changing the expression of miRNAs in the prevention and treatment of cancer.

MiR-148a-3p Promotes Colorectal Cancer Cell Ferroptosis by Targeting SLC7A11

Ferroptosis, an iron-dependent form of cell death, and dysregulated microRNA (miRNA) expression correlate with colorectal cancer (CRC) development and progression. The tumor suppressor ability of miR-148a-3p has been reported for several cancers. Nevertheless, the role of miR-148a-3p in CRC remains largely undetermined. Here, we aim at investigating the molecular mechanisms and regulatory targets of miR-148a-3p in the CRC cell death mechanism(s). To this end, miR-148a-3p expression was evaluated in SW480 and SW620 cells and normal colon epithelial CCD 841 CoN cells with quantitative real-time polymerase chain reaction (qRT-PCR). Data reported a reduction of miR-148a-3p expression in SW480 and SW620 cells compared to non-tumor cells (p < 0.05). Overexpression of miR-148a selectively inhibited CRC cell viability (p < 0.001), while weakly affecting normal CCD 841 CoN cell survival (p < 0.05). At the cellular level, miR-148a-3p mimics promoted apoptotic cell death via caspase-3 activation (p < 0.001), accumulation of mitochondrial reactive oxygen species (ROS) (p < 0.001), and membrane depolarization (p < 0.001). Moreover, miR-148a-3p overexpression induced lipid peroxidation (p < 0.01), GPX4 downregulation (p < 0.01), and ferroptosis (p < 0.01), as revealed by intracellular and mitochondrial iron accumulation and ACSL4/TFRC/Ferritin modulation. In addition, levels of SLC7A11 mRNA and protein, the cellular targets of miR-148a-3p predicted by bioinformatic tools, were suppressed by miR-148a-3p's overexpression. On the contrary, the downregulation of miR-148a-3p boosted SLC7A11 gene expression and suppressed ferroptosis. Together, these in vitro findings reveal that miR-148a-3p can function as a tumor suppressor in CRC by targeting SLC7A11 and activating ferroptosis, opening new perspectives for the rationale of therapeutic strategies through targeting the miR-148a-3p/SLC7A11 pathway.

Progress of regulatory RNA in small extracellular vesicles in colorectal cancer

Colorectal cancer (CRC) is the second most common malignant tumor of the gastrointestinal tract with the second highest mortality rate and the third highest incidence rate. Early diagnosis and treatment are important measures to reduce CRC mortality. Small extracellular vesicles (sEVs) have emerged as key mediators that facilitate communication between tumor cells and various other cells, playing a significant role in the growth, invasion, and metastasis of cancer cells. Regulatory RNAs have been identified as potential biomarkers for early diagnosis and prognosis of CRC, serving as crucial factors in promoting CRC cell proliferation, invasion and metastasis, angiogenesis, drug resistance, and immune cell differentiation. This review provides a comprehensive summary of the vital role of sEVs as biomarkers in CRC diagnosis and their potential application in CRC treatment, highlighting their importance as a promising avenue for further research and clinical translation.

Whey Improves In Vitro Endothelial Mitochondrial Function and Metabolic Redox Status in Diabetic State

Endothelial dysfunction plays a critical role in the progression of type 2 diabetes mellitus (T2DM), leading to cardiovascular complications. Current preventive antioxidant strategies to reduce oxidative stress and improve mitochondrial function in T2DM highlight dietary interventions as a promising approach, stimulating the deepening of knowledge of food sources rich in bioactive components. Whey (WH), a dairy by-product with a considerable content of bioactive compounds (betaines and acylcarnitines), modulates cancer cell metabolism by acting on mitochondrial energy metabolism. Here, we aimed at covering the lack of knowledge on the possible effect of WH on the mitochondrial function in T2DM. The results showed that WH improved human endothelial cell (TeloHAEC) function during the in vitro diabetic condition mimicked by treating cells with palmitic acid (PA) (0.1 mM) and high glucose (HG) (30 mM). Of note, WH protected endothelial cells from PA+HG-induced cytotoxicity (p < 0.01) and prevented cell cycle arrest, apoptotic cell death, redox imbalance, and metabolic alteration (p < 0.01). Moreover, WH counteracted mitochondrial injury and restored SIRT3 levels (p < 0.01). The SiRNA-mediated suppression of SIRT3 abolished the protective effects exerted by WH on the mitochondrial and metabolic impairment caused by PA+HG. These in vitro results reveal the efficacy of whey as a redox and metabolic modulator in the diabetic state and pave the way for future studies to consider whey as the source of dietary bioactive molecules with health benefits in preventive strategies against chronic diseases.

Inhibition of Galectins and the P2X7 Purinergic Receptor as a Therapeutic Approach in the Neurovascular Inflammation of Diabetic Retinopathy

Diabetic retinopathy (DR) is the most frequent microvascular retinal complication of diabetic patients, contributing to loss of vision. Recently, retinal neuroinflammation and neurodegeneration have emerged as key players in DR progression, and therefore, this review examines the neuroinflammatory molecular basis of DR. We focus on four important aspects of retinal neuroinflammation: (i) the exacerbation of endoplasmic reticulum (ER) stress; (ii) the activation of the NLRP3 inflammasome; (iii) the role of galectins; and (iv) the activation of purinergic 2X7 receptor (P2X7R). Moreover, this review proposes the selective inhibition of galectins and the P2X7R as a potential pharmacological approach to prevent the progression of DR.

Potential Pathogenic Impact of Cow’s Milk Consumption and Bovine Milk-Derived Exosomal MicroRNAs in Diffuse Large B-Cell Lymphoma

Epidemiological evidence supports an association between cow’s milk consumption and the risk of diffuse large B-cell lymphoma (DLBCL), the most common non-Hodgkin lymphoma worldwide. This narrative review intends to elucidate the potential impact of milk-related agents, predominantly milk-derived exosomes (MDEs) and their microRNAs (miRs) in lymphomagenesis. Upregulation of PI3K-AKT-mTORC1 signaling is a common feature of DLBCL. Increased expression of B cell lymphoma 6 (BCL6) and suppression of B lymphocyte-induced maturation protein 1 (BLIMP1)/PR domain-containing protein 1 (PRDM1) are crucial pathological deviations in DLBCL. Translational evidence indicates that during the breastfeeding period, human MDE miRs support B cell proliferation via epigenetic upregulation of BCL6 (via miR-148a-3p-mediated suppression of DNA methyltransferase 1 (DNMT1) and miR-155-5p/miR-29b-5p-mediated suppression of activation-induced cytidine deaminase (AICDA) and suppression of BLIMP1 (via MDE let-7-5p/miR-125b-5p-targeting of PRDM1). After weaning with the physiological termination of MDE miR signaling, the infant’s BCL6 expression and B cell proliferation declines, whereas BLIMP1-mediated B cell maturation for adequate own antibody production rises. Because human and bovine MDE miRs share identical nucleotide sequences, the consumption of pasteurized cow’s milk in adults with the continued transfer of bioactive bovine MDE miRs may de-differentiate B cells back to the neonatal “proliferation-dominated” B cell phenotype maintaining an increased BLC6/BLIMP1 ratio. Persistent milk-induced epigenetic dysregulation of BCL6 and BLIMP1 expression may thus represent a novel driving mechanism in B cell lymphomagenesis. Bovine MDEs and their miR cargo have to be considered potential pathogens that should be removed from the human food chain.