Exosome-loaded scaffolds for regenerative medicine in hard tissues

Tissue engineering can be used to repair tissue by employing bioscaffolds that provide better spatial control, porosity, and a three-dimensional (3D) environment like the human body. Optimization of injectability, biocompatibility, bioactivity, and controlled drug release are also features of such scaffolds. The 3D shape of the scaffold can control cell interaction and improve cell migration, proliferation, and differentiation. Exosomes (EXOs) are nanovesicles that can regulate osteoblast activity and proliferation using a complex composition of lipids, proteins, and nucleic acids in their vesicles. Due to their excellent biocompatibility and efficient cellular internalization, EXOs have enormous potential as desirable drug/gene delivery vectors in the field of regenerative medicine. They can cross the biological barrier with minimal immunogenicity and side effects. Scaffolds that contain EXOs have been studied extensively in both basic and preclinical settings for the regeneration and repair of both hard (bone, cartilage) and soft (skin, heart, liver, kidney) tissue. Cell motility, proliferation, phenotype, and maturation can all be controlled by EXOs. The angiogenic and anti-inflammatory properties of EXOs significantly influence tissue healing. The current study focused on the use of EXO-loaded scaffolds in hard tissue regeneration.

Beyond Protein Synthesis; The Multifaceted Roles of Tuberin in Cell Cycle Regulation

The ability of cells to sense diverse environmental signals, including nutrient availability and conditions of stress, is critical for both prokaryotes and eukaryotes to mount an appropriate physiological response. While there is a great deal known about the different biochemical pathways that can detect and relay information from the environment, how these signals are integrated to control progression through the cell cycle is still an expanding area of research. Over the past three decades the proteins Tuberin, Hamartin and TBC1D7 have emerged as a large protein complex called the Tuberous Sclerosis Complex. This complex can integrate a wide variety of environmental signals to control a host of cell biology events including protein synthesis, cell cycle, protein transport, cell adhesion, autophagy, and cell growth. Worldwide efforts have revealed many molecular pathways which alter Tuberin post-translationally to convey messages to these important pathways, with most of the focus being on the regulation over protein synthesis. Herein we review the literature supporting that the Tuberous Sclerosis Complex plays a critical role in integrating environmental signals with the core cell cycle machinery.

The effects of Salvia officinalis L. on granulosa cells and in vitro maturation of oocytes in mice

BACKGROUND

Salvia officinalisL. has been used since ancient times but there are little data about effects of this herb on normal reproductive cells.

OBJECTIVE

To investigate the toxicity effects of Salvia officinalis L. on granulosa cells (GCs) and maturation of oocytes.

MATERIALS AND METHODS

GCs and oocytes were extracted from superovulated ovaries of immature mice. The cells were treated with concentrations of 10, 50, 100, 500, and 1000 μg/ml of Salvia officinalis hydroalcoholic extracts and compared with the control culture. Bioviability, chromatin condensation, estradiol and progesterone concentrations, lipid synthesis, apoptosis, and alkaline phosphatase activity of GCs were measured. In vitro maturation of oocytes by determination of different maturation stages of oocytes including germinal vesicle, germinal vesicle breaks down, and metaphase II were examined.

RESULTS

The results revealed that 500 and 1000 μg/ml concentrations of Salvia officinalisL. were toxic. The most of the GCs were in the early stages of apoptosis in 100 μg/ml treated culture and cell death happened with 500 μg/ml treatment. Progesterone concentration was reduced in 100 μg/ml and higher doses but estradiol concentration and alkaline phosphatase showed opposite effects. The lipid droplets content of GCs reduced significantly in all groups especially in 500 and 1000 μg/ml. Finally, oocyte's nucleus and cytoplasm showed a high level of condensation, and meiosis rate reduced in all treated cultures.

CONCLUSION

Our findings suggested that higher dose of Salvia officinalis hydroalcoholic extracts inhibits, oocyte maturation, GCs bioviability, proliferation, and secretion.