Characterization of metabolic patterns in porcine cumulus cells during meiotic maturation.

Metabolic coupling between oocytes and the surrounding somatic cells allows for normal two-way communication, and their interactions is necessary for generating developmentally competent eggs. However, the metabolic framework that support oocyte maturation in surrounding cumulus cells is still lacking. Herin, we established a temporal metabolome profile of porcine cumulus cells at three key stages during oocyte maturation, illustrating the picture of global metabolic network in cumulus cells. Importantly, we discovered the novel metabolic signature in cumulus cells during meiotic maturation, in specific, significant consumption of fatty acids, elevated activity of hexosamine biosynthetic pathway (HBP), and enhanced polyamine biosynthesis. Meanwhile, we observed the different utilization of tryptophan, active biosynthesis of progesterone, and progressive decrease in purine and pyrimidine metabolism as the oocytes progress through meiosis. Collectively, our metabolomic data serves an entree to elaborate on the dynamic changes in these metabolic pathways, which not only reveals the metabolic networks controlling oocyte development, but also lays a foundation for the discovery of biomarkers in the improvement in porcine oocyte culture system.

Outcomes of Transjugular Intrahepatic Portosystemic Shunt and Gastric Coronary Vein Embolization for Variceal Bleeding in Cirrhotic Portal Hypertension.

Purpose: To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) combined with gastric coronary vein embolization (GCVE) for cirrhotic portal hypertensive variceal bleeding and compare outcomes of first-line with second-line treatment, coil with glue, and single-covered with double stents.Methods: Fifteen patients received TIPS plus GCVE as the first-line treatment for secondary prophylaxis of variceal bleeding, and 45 received it as second-line treatment. Preoperative and postoperative quantitative variables were compared using a paired t test. The incidence of survival rate, re-bleeding, hepatic encephalopathy, and shunt dysfunction were analyzed using the Kaplan-Meier method.Results: The portal venous pressure was significantly decreased from 39.0 ± 5.0 mm Hg to 22.5 ± 4.4 mm Hg (P≤0.001) after TIPS treatment. After 1, 3, 6, 12, 18, and 24 months re-bleeding rates were 1.6%, 3.3%, 6.6%, 13.3%, 0%, and 0%, respectively. Shunt dysfunction rates were 5%, 0%, 10%, 16.6%, 1.6%, and 5%, respectively. Hepatic encephalopathy rates were 3.3%, 1.6%, 3.3%, 6.6%, 0%, and 0%, respectively. And survival rates were 100%, 100%, 100%, 96.6%, 93.3%, and 88.3% respectively. In comparative analysis, statistically significant differences were seen in re-bleeding between the first-line and second-line treatment groups (26.6% vs 24.4%, log-rank P=0.012), and survival rates between single-covered and double stent (3.7% vs 16.1%, log-rang (P=0.043).Conclusion: The results suggest that TIPS combined with GCVE is effective and safer in the treatment of cirrhotic portal hypertensive variceal bleeding. The use of TIP plus GCVE as first-line treatment, may be preferable for high-risk re-bleeding, and more than 25 mm Hg portal venous pressure with repeated variceal bleeding. However, the sample size was small. Therefore, large, randomized, controlled, multidisciplinary center studies are needed for further evaluation.

Melatonin ameliorates histone modification disorders in mammalian aged oocytes by neutralizing the alkylation of HDAC1.

Aging-associated histone modification changes in oocytes have been sporadically reported, but the underlying mechanisms remain elusive. Here, we systematically characterize multiple histone modifications in oocytes during aging. We find that maternal and postovulatory aging markedly alter the status of histone modifications, specifically H4K12ac and H3K4me3, in both mouse and porcine oocytes. Meanwhile, we identify a substantial reduction in HDAC1 (histone deacetylase 1) protein in aged oocytes, which contributes to the changes in H4K12ac and H3K4me3. Moreover, by employing methylglyoxal (MG) and site-directed mutagenesis, we demonstrate that the elevated reactive carbonyl species (RCS) level induces HDAC1 degradation, likely through attacking the cysteine residues, thereby influences histone modification state. Importantly, supplementation of melatonin not only prevents the loss of HDAC1 protein, but also partially corrects the H4K12ac and H3K4me3 status in aged oocytes. To sum up, this study established the link between redox disequilibrium and histone modification alterations during mammalian oocyte aging.

Controlled-release alginate-bentonite polymer gel granules of emamectin benzoate and control efficacy against Spodoptera frugiperda.

BACKGROUND: The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is known to cause large agricultural production losses. Emamectin benzoate is one of the most effective insecticides to control this pest; however, its effective time is not sufficiently long to control FAW. Therefore, it is important that new controlled insecticide formulations with new application methods are developed. RESULTS: A series of emamectin benzoate polymer gel granules were prepared with sizes ranging from 0.95 to 1.5 mm. As the bentonite content increased, the release rate decreased. The cumulative release process of emamectin benzoate mainly depends on the cracks in the surface of the granules, and the release rate can be described by non-Fickian and Fickian diffusion, which are closely related to the water content. By spreading the developed polymer gel granules into maize leaf whorls, the control effect reached 83% after 21 days in field trials. CONCLUSION: A novel polymer gel granule was developed that can effectively regulate emamectin benzoate release. By broadcasting polymer gel granules into maize leaf whorls, significant control efficacy against FAW can be obtained, and this could potentially be used for the effective control of FAW. © 2022 Society of Chemical Industry.

ASB7 Is a Novel Regulator of Cytoskeletal Organization During Oocyte Maturation.

Ankyrin repeat and SOCS box (ASB) family members have a C-terminal SOCS box and an N-terminal ankyrin-related sequence of variable repeats. To date, the roles of ASB family members remain largely unknown. In the present study, by employing knockdown analysis, we investigated the effects of ASB7 on mouse oocyte meiosis. We show that specific depletion of ASB7 disrupts maturational progression and meiotic apparatus. In particular, abnormal spindle, misaligned chromosomes, and loss of cortical actin cap are frequently observed in ASB7-abated oocytes. Consistent with this observation, incidence of aneuploidy is increased in these oocytes. Meanwhile, confocal scanning reveals that loss of ASB7 impairs kinetochore-microtubule interaction and provokes the spindle assembly checkpoint during oocyte meiosis. Furthermore, we find a significant reduction of ASB7 protein in oocytes from aged mice. Importantly, increasing ASB7 expression is capable of partially rescuing the maternal age-induced meiotic defects in oocytes. Together, our data identify ASB7 as a novel player in regulating cytoskeletal organization and discover the potential effects of ASB7 on quality control of aging oocytes.

Loss of HDAC3 contributes to meiotic defects in aged oocytes.

Maternal age-related decline in oocyte quality is associated with meiotic defects, but the underlying mechanisms remain to be explored. Histone deacetylase 3 (HDAC3) has been shown to govern multiple cellular events via deacetylating diverse substrates. We previously found that HDAC3 could promote meiotic apparatus assembly in mouse oocytes. In the present study, we identified a substantial reduction in HDAC3 protein in oocytes from old mice. Importantly, overexpression of HDAC3 in old oocytes not only partially prevents spindle/chromosome disorganization, but also significantly lowers the incidence of aneuploidy. Meanwhile, we noticed the elevated acetylation level of α-tubulin in oocytes derived from old mice. By employing site-directed mutagenesis, we showed that acetylation-mimetic mutant tubulin-K40Q disrupts the kinetochore-microtubule attachments and results in the assembly failure of meiotic apparatus in mouse oocytes. Importantly, forced expression of tubulin-K40R (nonacetylatable-mimetic mutant) was capable of alleviating the defective phenotypes of oocytes from aged mice. To sum up, this study uncovers that loss of HDAC3 represents one potential mechanism mediating the effects of advanced maternal age on oocyte quality.

Characterization and Expression of Genes Encoding Superoxide Dismutase in the Oriental Armyworm, Mythimna separata (Lepidoptera: Noctuidae).

Superoxide dismutase (SOD) is an antioxidant metalloenzyme that catalyzes the dismutation of the superoxide anion O2- to O2 and H2O2. Many studies have focused on the role of SOD in response to abiotic stress, but its role during biotic stress, such as changes in organismal population density, has rarely been investigated. The oriental armyworm, Mythimna separata, is an economically important pest that exhibits phenotypic changes in response to population density. Solitary and gregarious phases occur at low and high population density, respectively. To examine the role of SODs in response to population density stress, we cloned two genes encoding SOD, MsCuZnSOD and MsMnSOD, and compared their expression in solitary and gregarious phases of M. separata. The MsCuZnSOD and MsMnSOD ORFs were 480 and 651 bp and encoded predicted protein products of 159 and 216 amino acids, respectively. The two SODs contained motifs that are typical of orthologous proteins. Real-time PCR indicated that the two SOD genes were expressed throughout developmental stages and were significantly upregulated in more mature stages of gregarious M. separata. Expression of the two SOD genes in various tissues of sixth-instar larvae was higher in gregarious versus solitary insects. Furthermore, expression of the SOD genes was significantly upregulated in response to crowding in solitary individuals, but suppressed in gregarious insects subjected to isolation. Collectively, these results suggest that population density may be key factor in the induction of SOD genes in M. separata.

HDAC3 inhibition disrupts the assembly of meiotic apparatus during porcine oocyte maturation.

Histone deacetylases (HDACs) are involved in a wide array of biological processes. However, the role of HDAC3 in porcine oocytes remains unclear. In the current study, we examine the effects of HDAC3 inhibition on porcine oocyte maturation using RGFP966, a selective HDAC3 inhibitor. We find that suppression of HDAC3 activity prevents not only the expansion of cumulus cells but also the meiotic progression of oocytes. It is interesting to note that HDAC3 displays a spindle-like distribution pattern as the porcine oocytes enter meiosis. In line with this, confocal microscopy reveals the high frequency of spindle defects and chromosomal congression failure in metaphase oocytes exposed to RGFP966. Moreover, HDAC3 inhibition results in the hyperacetylation of α-tubulin during oocyte meiosis. These findings indicate that HDAC3 activity might control the microtubule stability via the deacetylation of tubulin, which is critical for maintaining the proper spindle assembly, accurate chromosome separation, and orderly meiotic progression during porcine oocyte maturation.

Intersectin-Cdc42 interaction is required for orderly meiosis in porcine oocytes.

Intersectins (ITSNs) have been shown to act as adaptor proteins that govern multiple cellular events via regulating Cdc42 activity. However, it remains to be determined whether the ITSN-Cdc42 pathway is functional in porcine oocytes. To address this question, we used a small molecule, ZCL278, to selectively disrupt the ITSN2-Cdc42 interaction. In the present study, we find that porcine oocytes exposed to ZCL278 are unable to completely progress through meiosis. Meanwhile, the spindle defects and chromosomal congression failure are frequently detected in these oocytes. In support of this, we observed the accumulated distribution of vesicle-like ITSN2 signals around the chromosome/spindle region during porcine oocyte maturation. In addition, our results also showed that inhibition of the ITSN-Cdc42 interaction impairs the actin polymerization in porcine oocytes. In summary, the findings support a model where ITSNs, through the interaction with Cdc42, modulates the assembly of meiotic apparatus and actin polymerization, consequently ensuring the orderly meiotic progression during porcine oocyte maturation.

SIRT7 functions in redox homeostasis and cytoskeletal organization during oocyte maturation.

SIRT7, a member of the sirtuin family, with coenzyme NAD catalyzes protein deacetylation and has been implicated in multiple biologic processes; however, its function in mammalian oocytes remains to be explored. Here, we report disrupted meiotic maturation upon specific knockdown of SIRT7 in mouse oocytes. In particular, disorganized spindle/chromosomes and the loss of the cortical actin cap are readily observed in SIRT7-depleted oocytes, generating aneuploid eggs. Furthermore, we found that SIRT7 depletion markedly elevated reactive oxygen species levels in oocytes, thereby compromising the developmental competence of early embryos. Of note, SIRT7 protein level is significantly decreased in oocytes from obese mice, and the forced expression of exogenous SIRT7 ameliorates maternal obesity-associated meiotic defects and oxidative stress in oocytes. In summary, our data suggest that SIRT7 is an essential factor in the determination of oocyte quality and may mediate the effects of obesity on female reproduction.-Gao, M., Li, X., He, Y., Han, L., Qiu, D., Ling, L., Liu, H., Liu, J., Gu, L. SIRT7 functions in redox homeostasis and cytoskeletal organization during oocyte maturation.

Screening potential reference genes for quantitative real-time PCR analysis in the oriental armyworm, Mythimna separata.

The oriental armyworm, Mythimna separata, is a major insect pest in China and other Asian countries. Unfortunately, suitable reference genes for quantitative real-time PCR (qRT-PCR) have not been previously identified in M. separata for normalizing target gene expression. In this study, we evaluated the expression stability of eight candidate genes (18S, ACT, EF1-α, GAPDH, RPS7, RPS13, RPL32 and TUB) in M. separata using the comparative ΔCt method, BestKeeper, Normfinder geNorm and ReFinder, a comprehensive software platform. The results indicated that the appropriate reference gene varied depending on the experimental conditions. We found that ACTIN, EF1-α and TUB were optimal for different developmental stages; TUB, RPS13 and EF1-α showed the most stable expresssion in different tissues; RPS13 and 18S were the best reference genes for monitoring expression under high temperature conditions; TUB, RPS13 and RPS7 exhibited the most stable expression under larval-crowding conditions; RPS7, EF1-α, RPL32 and GAPDH were the best for pesticide exposure experiments. This study provides tools for reliable normalization of qRT-PCR data and forms a foundation for functional studies of target gene expression in M. separata.