Vitamin K2 (MK-7) Intercepts Keap-1/Nrf-2/HO-1 Pathway and Hinders Inflammatory/Apoptotic Signaling and Liver Aging in Naturally Aging Rat.

Aging is a naturally occurring physiological process with a deleterious impact on various body organs and humans' well-being. The aging population is increasing worldwide, which imposes the need for the exploration of nutritional options that can intercept the impact of the aging processed on various body organs. Vitamin K2 (VK2) is a fat-soluble vitamin with emerging evidence on its therapeutic merits. In the current study, natural aging induced a significant liver deterioration with a disrupted Keap-1/Nrf-2/HO-1 axis and increased COX-2, iNOS and TNF-α expression and apoptotic and fibrotic changes. VK2 administration, on the other hand, improved the biochemical indices of liver function (total protein, albumin, ALT and AST); the suppressed hepatic expression of Keap-1 and increased the hepatic expression of Nrf-2 with a parallel increase in the hepatic activity of HO-1. Subsequently, the liver content and hepatic expression of TNF-α, COX-2 and iNOS were significantly retracted. In context, the liver content and hepatic expression of the fibrotic biomarkers TGFß and TIMP significantly retracted as well. Moreover, the TUNEL assay confirmed the retraction of liver apoptotic changes. Of notice, electron transmission microscope examination confirmed the preservation of mitochondrial functions and preservation of the ultra-microscopical structures. In conclusion, the VK2-mediated interception of aging-induced Keap-1/Nrf-2/HO-1 signaling suppressed the hepatic contents of inflammatory and fibrotic biomarkers, as well as apoptotic changes with preservation of the hepatic architectural and functional status. VK2 can be presumed to be an effective nutritional supplement to the aging population to spare the liver, amongst other body organs, against aging-induced deleterious injury.

Effect of bone marrow mesenchymal stem cells-derived exosomes on diabetes-induced retinal injury: Implication of Wnt/ b-catenin signaling pathway.

BACKGROUND: Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus. Mesenchymal stem cells are currently studied as therapeutic strategy for management of DR. Exosomes, considered as a promising cell-free therapy option, display biological functions similar to those of their parent cells. In retinal development, Wnt/b-catenin signaling provides key cues for functional progression. The present study aimed to evaluate the potential efficacy of bone marrow-derived mesenchymal stem cell-derived exosomes (BM-MSCs-Ex) in diabetes-induced retinal injury via modulation of the Wnt/ b-catenin signaling pathway. METHODS: Eighty-one rats were allocated into 6 groups (control, DR, DR + DKK1, DR + exosomes, DR + Wnt3a and DR + exosomes+Wnt3a). Evaluation of each group was via histopathological examination, assessment of gene and/or protein expression concerned with oxidative stress (SOD1, SOD2, Nox2, Nox4, iNOS), inflammation (TNF-α, ICAM-1, NF-κB) and angiogenesis (VEGF, VE-cadherin). RESULTS: Results demonstrated that exosomes blocked the wnt/b-catenin pathway in diabetic retina concomitant with significant reduction of features of DR as shown by downregulation of retinal oxidants, upregulation of antioxidant enzymes, suppression of retinal inflammatory and angiogenic markers. These results were further confirmed by histopathological results, fundus examination and optical coherence tomography. Additionally, exosomes ameliorative effects abrogated wnt3a-triggered retinal injury in DR. CONCLUSION: Collectively, these data demonstrated that exosomes ameliorated diabetes-induced retinal injury via suppressing Wnt/ b-catenin signaling with subsequent reduction of oxidative stress, inflammation and angiogenesis.

Dapagliflozin, Liraglutide, and Their Combination Attenuate Diabetes Mellitus-Associated Hepato-Renal Injury-Insight into Oxidative Injury/Inflammation/Apoptosis Modulation.

In this study, we aim to explore the beneficial therapeutic impacts of dapagliflozin (Dapa), a highly potent, reversible, and selective sodium-glucose cotransporter-2 inhibitor, and liraglutide (Lira), a glucagon-like peptide-1 (GLP-1) receptor agonist, as hypoglycaemic agents for the management of diabetes mellitus (DM), as well as their combination against DM-induced complications, including hepato-renal injury. Indeed, the progression of DM was found to be associated with significant hepatic and renal injury, as confirmed by the elevated biochemical indices of hepatic and renal functions, as well as histopathological examination. Dapa, Lira, and their combination effectively attenuated DM-induced hepatic and renal injury, as confirmed by the recovery of hepatic and renal functional biomarkers. The administration of both drugs significantly reduced the tissue contents of MDA and restored the contents of GSH and catalase activity. Moreover, NF-κB and TNF-α expression at the protein and gene levels was significantly reduced in the liver and the kidney. This was in parallel with the significant reduction in the caspase-3 content in the liver and the kidney, as well as suppressed cleaved caspase-3 expression in the hepatic and renal specimens, as confirmed by immune-histochemical analysis. Notably, the combined Dapa/Lira treatment demonstrated an additive superior hepato-renal protective impact compared with the use of either drug alone. Thus, it appears that Dapa and Lira, through the coordinated modulation of oxidative, inflammatory, and apoptotic signalling, confer a significant hepato-renal protective impact against DM-induced complications and tissue injury.