In vitro maturation (IVM) is emerging as a popular technology at the forefront of fertility treatment and preservation. However, standard in vitro culture (IVC) conditions usually increase reactive oxygen species (ROS), which have been implicated as one of the major causes for reduced embryonic development. It is well-known that higher than physiological levels of ROS trigger granulosa cell apoptosis and thereby reduce the transfer of nutrients and survival factors to oocytes, which leads to apoptosis. ROS are neutralized by an elaborate defense system that consists of enzymatic and non-enzymatic antioxidants. The balance between ROS levels and antioxidants within IVM media are important for maintenance of oocytes that develop to the blastocyst stage. The effects of antioxidant supplementation of IVM media have been studied in various mammalian species. Therefore, this article reviews and summarizes the effects of ROS on oocyte quality and the use of antioxidant supplementations for IVM, in addition to its effects on maturation rates and further embryo development.

The destructive effects of sperm cryopreservation result in decreased sperm parameters and their fertilizing ability. Antioxidants supplementation can potentially improve cryopreservation outcomes. In this study, we tried to investigate the effects of sericin supplementation in freezing and thawing media on frozen-thawed human sperm motility, morphology, viability, and DNA fragmentation. In experiment 1, semen samples were collected from 30 healthy fertile men and were cryopreserved in the presence of freezing medium supplemented with different concentrations of sericin (0, 0.5, 1, 2.5, and 5%). The results showed that the addition of 2.5 and 5% sericin in freezing medium significantly increased sperm viability and total motility (A + B) and decreased DNA fragmentation (P < 0.05). In experiment 2, semen samples were collected from 21 fertile men and were cryopreserved in freezing medium without any supplementation for 48 h. Then, the samples were thawed in medium supplemented with different concentrations of sericin (0, 0.5, 1, 2.5, and 5%). The addition of 5% sericin to thawing medium increased the total motility, viability, and decreased DNA fragmentation compared with those in thaws without sericin. In nutshell, the results clearly indicate the feasibility of sericin as an cryoprotective supplement for freezing media in human spermatozoa.

Platinum-based chemotherapeutic agents are widely employed in cancer treatment because of their effectiveness in targeting DNA. However, this indiscriminate action often affects both cancerous and normal cells, leading to severe side effects and highlighting the need for innovative approaches in achieving precise drug delivery. Nanotechnology presents a promising avenue for addressing these challenges. Protein-based nanocarriers exhibit promising capabilities in the realm of cancer drug delivery with silk sericin nanoparticles standing out as a leading contender. This investigation focuses on creating a sericin-based nanocarrier (SNC) featuring surface charge reversal designed to effectively transport cisplatin (Cispt-SNC) into MCF-7 breast cancer cells. Utilizing AutoDock4.2, our molecular docking analyses identified key amino acids and revealed distinctive conformational clusters, providing insights into the drug-protein interaction landscape and highlighting the potential of sericin as a carrier for controlled drug release. The careful optimization and fabrication of sericin as the carrier material were achieved through flash nanoprecipitation, a straightforward and reproducible method that is devoid of intricate equipment. The physicochemical properties of SNCs and Cispt-SNCs, particularly concerning size, surface charge, and morphology, were evaluated using dynamic light scattering (DLS) and scanning electron microscopy (SEM). Chemical and conformational analyses of the nanocarriers were conducted using Fourier-transform infrared spectroscopy (FTIR) and circular dichroism (CD), and elemental composition analysis was performed through energy-dispersive X-ray spectroscopy (EDX). This approach aimed to achieve the smallest nanoparticle size for Cispt-SNCs (180 nm) and high drug encapsulation efficiency (84%) at an optimal sericin concentration of 0.1% (w/v), maintaining a negative net charge at a physiological pH (7.4). Cellular uptake and cytotoxicity were investigated in MCF-7 breast cancer cells. SNCs demonstrated stability and exhibited a pH-dependent drug release behavior, aligning with the mildly acidic tumor microenvironment (pH 6.0-7.0). Efficient cellular uptake of Cispt-SNC, along with DNA fragmentation and chromatin condensation, was found at pH 6, leading to cell apoptosis. These results collectively indicate the potential of SNCs for achieving controlled drug release in a tumor-specific context. Our in vitro studies reveal the cytotoxicity of both cisplatin and Cispt-SNCs on MCF-7 cells. Cisplatin significantly reduced cell viability at 10 μM concentration (IC₅₀), and the unique combination of sericin and cisplatin showcased enhanced cell viability compared to cisplatin alone, suggesting that controlled drug release is indicated by a gradient decrease in cell viability and highlighting SNCs as promising carriers. The study underscores the promise of protein-based nanocarriers in advancing targeted drug delivery for cancer therapy.

L-Proline is a natural anti-oxidative and osmoprotectant agent, playing a versatile role in cell metabolism and physiology. The present study aimed to explore the antioxidant effects of L-Proline on human sperm function during incubation. Thirty healthy, normozoospermic men (27-40 years) were enrolled. Sperm samples were incubated in an unsupplemented sperm medium (control group), or supplemented with L-Proline (1, 2 and 4 mmol/L) to evaluate its effect during 0, 1, 4 and 24 h of incubation. Sperm were assessed in terms of motility, viability, morphology, chromatin and DNA integrity. Moreover, the levels of reactive oxygen species (ROS), malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined in the sperm medium. The results indicated that 2 mmol/L of L-Proline significantly improved the maintenance of sperm motility, viability, normal morphology, chromatin and DNA integrity, and TAC levels compared to the control group during 24 h of incubation (p < 0.05). However, 1 and 4 mmol/L of L-Proline could not significantly preserve sperm parameters, chromatin quality, and antioxidant status during different incubation times compared to the control group (p > 0.05). Collectively, the inclusion of L-Proline (2 mmol/L) in the human sperm medium maintains sperm parameters and chromatin quality probably by modulating the oxidative status.