Most eukaryotic and prokaryotic cells have the potential to secrete a group of structures/membrane-bound organelles, collectively referred to as extracellular vesicles (EVs), which offer several advantages to producer/receiver cells. This review provides an overview of EVs from plant sources with emphasis on their health-promoting potential and possible use as therapeutic agents. This review highlights the essential biological effects of plant-derived extracellular vesicles, including immune modulation, anticancer activities, protection against chemical toxicity and pathogens, as well as anti-aging, anti-melanogenesis, and anti-arthritic effects, along with ongoing clinical studies. Evidence revealed that plant-derived EVs’ contents exert their beneficial properties through regulating important signaling pathways by transferring miRNAs and other components. Taken all together, the data proposed that plant-derived EVs can be utilized as nutritional compounds and therapeutic agents, such as drug carriers. However, this emerging research area requires further in vitro/in vivo studies and clinical trials to determine the exact underlying mechanisms of EVs’ positive health effects in treating various diseases.
Methylsulfonylmethane (MSM) is a non-toxic, natural organosulfur compound, which is known to possess antioxidant and anti-inflammatory activities. In recent years, MSM has been widely used as a dietary supplement for its beneficial effects against various diseases, especially arthritis. Despite being a popular supplement product, the mechanism of action of MSM is not well known. This study was designed to investigate the effects of MSM on cytotoxic signals induced by lipopolysaccharide (LPS) and interferon-gamma (IFN-γ) in RAW 264.7 macrophage-like cells. The results showed that MSM reversed apoptosis of RAW 264.7 macrophage-like cells at non-cytotoxic concentrations probably through the modulation of apoptotic proteins. After pre-treatment of cells with non-toxic doses of MSM; caspase-3 activation, p53 accumulation, cytochrome c release and Bax/Bcl-2 ratio were significantly decreased and full length poly ADP-ribose polymerase (PARP) was significantly increased. In addition, the loss of mitochondrial membrane potential was decreased with MSM pretreatment in activated macrophages. Since excess nitric oxide production causes apoptosis of macrophages, anti-apoptotic effects of MSM are thought to be mediated by its inhibitor effects on inducible nitric oxide synthase (iNOS) protein and nitric oxide levels. More interestingly, higher doses of MSM exhibited biphasic effects, inhibited cell viability, induced apoptosis of macrophages, increased caspase-3 activity and PARP cleavage. Thus, our results reveal the molecular mechanism of of MSM indicating that MSM supplementation may be beneficial for complications related to nitric oxide-dependent apoptosis in inflammatory conditions. However, the optimum concentration of MSM must be chosen carefully to elicit the desired effect.
Introduction: Erectile dysfunction (ED) worsens in men with diabetes. Human umbilical cord blood (HUCB), because of its widespread availability and low immunogenicity, is a valuable source for stem cell-based therapies. Aim: To determine the effect of intracavernous injection of HUCB mononuclear cells (MNCs) on ED in rats with diabetes induced by streptozotocin. Methods: Thirty adult male Sprague-Dawley rats were equally divided into three groups: (i) control, (ii) diabetes induced by streptozotocin (35 mg/kg intravenously for 8 weeks), and (iii) diabetic rats treated with MNCs (1 × 106 cells by intracavernosal injection). The HUCB-MNCs isolated by the Ficoll-Hypaque technique were obtained from eight healthy donors and administered to diabetic rats after 4 weeks. Main Outcome Measures: The ratio of intracavernosal pressure to mean arterial pressure ratio; the protein expression of endothelial and neuronal markers, such as von Willebrand factor, neuronal nitric oxide synthase, hypoxia-inducible factor-1α, and vascular endothelium growth factor; and the relative area of smooth muscle to collagen using western blotting and Masson trichrome staining were determined. Results: Diabetic rats demonstrated a significantly decreased ratio of intracavernosal pressure to mean arterial pressure (0.26 ± 0.04; P < .01) and treatment with MNCs restored erectile function in diabetic rats (0.67 ± 0.05) compared with control rats (0.56 ± 0.02). In bath studies, neurogenic relaxant and contractile responses were significantly decreased in diabetic cavernosal tissues, which were restored by treatment. The ratio of smooth muscle to collagen was partly recovered by treatment, whereas von Willebrand factor levels were not altered in any group. Neuronal nitric oxide synthase and vascular endothelium growth factor levels were decreased, which were not restored by treatment. Increased hypoxia-inducible factor-1α protein expression in the diabetic group was completely normalized in MNC-treated diabetic samples. Conclusion: These results suggest that HUCB-MNC treatment can enhance the recovery of erectile function and promote numerous activities such the contribution of the hypoxia-inducible factor-1α and von Willebrand factor pathway to the neurogenic erectile response of diabetic rats. HUCB-MNCs in the healing process could involve an adaptive regenerative response and appear to be a potential candidate for cell-based therapy in ED of men with diabetes. It is evident that HUCB could provide a realistic therapeutic modality for the treatment of diabetic ED.