Retinoic acid loaded with chitosan nanoparticles improves spermatogenesis in scrotal hyperthermia in mice / 대한생식의학회지

Objective@#High temperatures can trigger cellular oxidative stress and disrupt spermatogenesis, potentially leading to male infertility. We investigated the effects of retinoic acid (RA), chitosan nanoparticles (CHNPs), and retinoic acid loaded with chitosan nanoparticles (RACHNPs) on spermatogenesis in mice induced by scrotal hyperthermia (Hyp). @*Methods@#Thirty mice (weighing 25 to 30 g) were divided into five experimental groups of six mice each. The groups were as follows: control, Hyp induced by a water bath (43 °C for 30 minutes/day for 5 weeks), Hyp+RA (2 mg/kg/day), Hyp+CHNPs (2 mg/kg/72 hours), and Hyp+RACHNPs (4 mg/kg/72 hours). The mice were treated for 35 days. After the experimental treatments, the animals were euthanized. Sperm samples were collected for analysis of sperm parameters, and blood serum was isolated for testosterone measurement. Testis samples were also collected for histopathology assessment, reactive oxygen species (ROS) evaluation, and RNA extraction, which was done to compare the expression levels of the bax, bcl2, p53, Fas, and FasL genes among groups. Additionally, immunohistochemical staining was performed. @*Results@#Treatment with RACHNPs significantly increased stereological parameters such as testicular volume, seminiferous tubule length, and testicular cell count. Additionally, it increased testosterone concentration and improved sperm parameters. We observed significant decreases in ROS production and caspase-3 immunostaining in the RACHNP group. Moreover, the expression levels of bax, p53, Fas, and FasL significantly decreased in the groups treated with RACHNPs and RA. @*Conclusion@#RACHNPs can be considered a potent antioxidative and antiapoptotic agent for therapeutic strategies in reproductive and regenerative medicine.

Comparison of different crosslinking methods for preparation of docetaxel-loaded albumin nanoparticles

In the last step of desolvation method for preparation of albumin nanoparticles, glutaraldehyde [GA] is added to stabilize the newly formed nanoparticles. Due to undesirable effects of GA, the objective of this study was to evaluate alternative methods of crosslinking including ultraviolet [UV] irradiation, adding of glucose and combination of both methods. The nanoparticles were prepared by desolvation procedure. Final particle size, zeta potential, FTIR, scanning electron micrograph, cellular uptake and cell toxicity of nanoparticles crosslinked with UV and/or glucose were compared with commonly crosslinked nanoparticles with GA. Moreover, drug release and stability parameters of docetaxel-loaded albumin nanoparticles were investigated. Size of all nanoparticles prepared by different methods was in the same range [100-200 nm]. Zeta potential showed the same results except for those treated with UV. The results of FTIR assay were the same for all groups. Although crosslinking by UV or glucose alone resulted in cytotoxic effects, combination of UV and glucose had less cytotoxic effects compared to GA. Cellular uptake of nanoparticles crosslinked with UV + glucose and GA showed similar results. The release of docetaxel from UV + glucose and GA crosslinked nanoparticles showed the same biphasic release. These data support the idea that crosslinking with a combination of UV and glucose can be a promising alternative method for production of docetaxel-loaded albumin nanoparticles with the advantage of omitting toxic GA

[Determination of antibacterial effect of the epithelial and mesenchymal surfaces of amniotic membrane on Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa]

Human amniotic membrane due to its unique characteristics, has many applications various fields of medicine and tissue engineering. One of these characteristics is antibacterial property, which can be important in protection against infections after burn and surgery. This study was designed aiming at investigating the antibacterial effect of amnion on the growth of different bacterial strains and comparing this effect in epithelial and mesenchymal sides of the amnion. In this study, the antibacterial effect of amniotic membrane was evaluated on three standard bacterial strains Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853 and two clinical isolated strain of E. coli [E. coli T3 and E. coli T4], and their susceptibility was measured. A modified disk diffusion test was used to assess the antibacterial effect. In this method, amnion was placed on the cultured agar surface as an antibiotic releasing disk. Statistical analysis was performed using analysis of variance and Tukey's tests. The vicinity of amnion membrane caused inhibition zone against Pseudomonas aeruginosa ATCC 27853 and two clinical isolated strains of E. coli. Formation of Inhibition zone in Pseudomonas aeruginosa ATCC 27853 and two clinical isolated strains of E. coli had no relationship with the epithelial or mesenchymal side of amniotic membrane. According to the results of this study, it seems that the type of bacterial strain has a role in the antibacterial effect of amnion membrane. In addition, both sides of amnion [epithelial and mesenchymal] may have similar antibacterial effect

effect of cryopreservation and lyophilization on histological and mechanical properties of human amniotic membrane

Introduction and Objective: The amniotic membrane [AM] has distinctive characteristics and potentials that make it a proper biomaterial for tissue engineering. There are varieties of methods for preserving the AM. In this study, the AM was preserved using different methods. The effect of preservation on tissue composition and physical and mechanical properties was compared between preserved and fresh samples of the AM

Materials and Methods: The human AM was preserved after being detached from the placenta. It was preserved using either cryopreservation methods [in temperature of -80 ?C, for 6 months] or lyophilization. The preserved AM was histologically assessed using light and electronic microscopy. Mechanical tolerance of the preserved AM was also measured using uniaxial tension test, suture retention test and thickness calculation

Results: This study showed that the value of Fmax and elongation at break in the cryopreserved and lyophilaized AM was smaller than the same value in the fresh AM samples. All of the samples had same tolerance in suture retention test, although lyophilaized samples of the AM were thinner than other types of the samples. Tissue composition [histological properties] regarding epithelial cells and tissue layers of the AM were not the same in different samples

Conclusion: Cryopreservation and lyophilization as two preservation methods of the AM, can affect the tissue composition and physical and mechanical features of the AM. Thus the preservation method for the AM can be chosen regarding the final usage of the AM as a biomaterial