Pnserpin: A Novel Serine Protease Inhibitor from Extremophile Pyrobaculum neutrophilum.

Serine protease inhibitors (serpins) are native inhibitors of serine proteases, constituting a large protein family with members spread over eukaryotes and prokaryotes. However, only very few prokaryotic serpins, especially from extremophiles, have been characterized to date. In this study, Pnserpin, a putative serine protease inhibitor from the thermophile Pyrobaculum neutrophilum, was overexpressed in Escherichia coli for purification and characterization. It irreversibly inhibits chymotrypsin-, trypsin-, elastase-, and subtilisin-like proteases in a temperature range from 20 to 100 °C in a concentration-dependent manner. The stoichiometry of inhibition (SI) of Pnserpin for proteases decreases as the temperature increases, indicating that the inhibitory activity of Pnserpin increases with the temperature. SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) showed that Pnserpin inhibits proteases by forming a SDS-resistant covalent complex. Homology modeling and molecular dynamic simulations predicted that Pnserpin can form a stable common serpin fold. Results of the present work will help in understanding the structural and functional characteristics of thermophilic serpin and will broaden the current knowledge about serpins from extremophiles.

Immunological mechanisms of inflammatory diseases caused by gut microbiota dysbiosis: A review.

The gut microbiota is indispensable for maintaining host health by enhancing the host's digestive capacity, safeguarding the intestinal epithelial barrier, and preventing pathogen invasion. Additionally, the gut microbiota exhibits a bidirectional interaction with the host immune system and promotes the immune system of the host to mature. Dysbiosis of the gut microbiota, primarily caused by factors such as host genetic susceptibility, age, BMI, diet, and drug abuse, is a significant contributor to inflammatory diseases. However, the mechanisms underlying inflammatory diseases resulting from gut microbiota dysbiosis lack systematic categorization. In this study, we summarize the normal physiological functions of symbiotic microbiota in a healthy state and demonstrate that when dysbiosis occurs due to various external factors, the normal physiological functions of the gut microbiota are lost, leading to pathological damage to the intestinal lining, metabolic disorders, and intestinal barrier damage. This, in turn, triggers immune system disorders and eventually causes inflammatory diseases in various systems. These discoveries provide fresh perspectives on how to diagnose and treat inflammatory diseases. However, the unrecognized variables that might affect the link between inflammatory illnesses and gut microbiota, need further studies and extensive basic and clinical research will still be required to investigate this relationship in the future.

Synthesis of Poly-γ-Glutamic Acid and Its Application in Biomedical Materials.

Poly-γ-glutamic acid (γ-PGA) is a natural polymer composed of glutamic acid monomer and it has garnered substantial attention in both the fields of material science and biomedicine. Its remarkable cell compatibility, degradability, and other advantageous characteristics have made it a vital component in the medical field. In this comprehensive review, we delve into the production methods, primary application forms, and medical applications of γ-PGA, drawing from numerous prior studies. Among the four production methods for PGA, microbial fermentation currently stands as the most widely employed. This method has seen various optimization strategies, which we summarize here. From drug delivery systems to tissue engineering and wound healing, γ-PGA's versatility and unique properties have facilitated its successful integration into diverse medical applications, underlining its potential to enhance healthcare outcomes. The objective of this review is to establish a foundational knowledge base for further research in this field.

Role and mechanism of alpa1-antitrypsin in polycystic ovary syndrome.

OBJECTIVES: To determine the relationships among alpha1-antitrypsin (A1AT), pro-inflammatory cytokines, neutrophil elastase (NE), interleukin (IL)- 1ß, and IL-8 in cases with polycystic ovary syndrome (PCOS). METHODS: Female rats in the control group were fed and watered normally. Female rats in the PCOS group were given high-fat diets and letrozole (1% carboxymethyl cellulose' [CMC] solution) CMC by gavage at a dose of l mg/kg body weight daily for 23 days. The mRNA levels of A1AT and NE in rat ovaries were detected by performing real-time polymerase chain reaction (PCR) in the laboratory of Norman Bethune College of Medicine, Jilin University, China in 2017. All serum samples were collected from the Second Hospital of Jilin University from October 2021 to November 2021 for obesity concurrent with PCOS. Molecular docking of A1AT with NE, IL-8, and IL-1ß was investigated using the Insight II software ZDOCK tool. This study was carried out at the Reproductive Center, The Second Hospital of Jilin University, Changchun, China from June 2021 to July 2022. RESULTS: The expression of the A1AT mRNA decreased in the ovary tissues of PCOS rats relative to that of healthy controls, while the expression of NE mRNA increased compared to that of normal controls. The serum A1AT expression in PCOS cases decreased considerably relative to their expression in normal controls. However, the expression of NE, IL-1ß, and IL-8 increased significantly relative to their expression in the control (p<0.05 for all). The Insight II ZDOCK molecular docking simulations showed that A1AT has direct interaction sites for NE, IL-1ß, and IL-8. CONCLUSION: Alpha1-antitrypsin is closely associated with NE, IL-1ß, and IL-8. Therefore, we speculate that A1AT might ameliorate PCOS symptoms by inhibiting pro-inflammatory factors: NE, IL-1ß, and IL-8.

Assessment of released acrosin activity as a measurement of the sperm acrosome reaction.

AIM: To develop a method for assessing sperm function by measuring released acrosin activity during the acrosome reaction (AR). METHODS: Human semen samples were obtained from 24 healthy donors with proven fertility after 3-7 days of sexual abstinence. After collection, samples were liquefied for 30 min at room temperature. Standard semen parameters were evaluated according to World Health Organization (WHO) criteria. Calcium ionophore A23187 and progesterone (P4) were used to stimulate the sperm to undergo AR. After treatment, sperm were incubated with the supravital dye Hoechst33258, fixed in a glutaraldehyde-phosphate-buffered saline solution, and the acrosomal status was determined by fluorescence microscopy with fluorescein isothiocyanate-labeled Pisum sativum agglutinin (FITC-PSA). The percentage of sperm undergoing AR (AR%) was compared to sperm acrosin activities as assessed by spectrocolorimetry. The correlation between AR% and acrosin activity was determined by statistical analysis. RESULTS: The AR% and released acrosin activity were both markedly increased with A23187 and P4 stimulation. Sperm motility and viability were significantly higher after stimulation with P4 versus stimulation with A23187 (P < 0.001). There was a significant positive correlation between released acrosin activity and AR% determined by FITC-PSA staining (r=0.916, P < 0.001). CONCLUSION: Spectrocolorimetric measurement of released acrosin activity might serve as a reasonable alternative method to evaluate AR.

DhHP­6 attenuates cerebral ischemia­reperfusion injury in rats through the inhibition of apoptosis.

As a novel reactive oxygen species (ROS) scavenger, deuterohemin His peptide­6 (DhHP­6) has been demonstrated to prolong the lifespan of Caenorhabditis elegans and has also exhibited protective effects in myocardial ischemia­reperfusion injury. Whether similar effects occur during cerebral ischemia­reperfusion (CIR) injury remains to be elucidated. The present study evaluated the function of DhHP­6 and its underlying mechanisms in a middle cerebral artery occlusion (MCAO) model in rats. The focal transient MCAO model was implemented using the Longa method of ischemia for 2 h followed by reperfusion for 22 h in male Wistar rats. DhHP­6 was administered at the onset of reperfusion via intraperitoneal injection. The infarct volume, brain edema, brain apoptosis and neurological function were evaluated 24 h following stroke. To further determine the role of DhHP­6 in CIR injury, the levels of ROS and malondialdehyde (MDA), the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH­Px), and the protein expression levels of B­cell lymphoma 2 (Bcl­2)­associated X protein (Bax), cleaved caspase­3, cytochrome c, Bcl­2 and phosphorylated­Akt/Akt were measured in ischemic cortex tissues. The results demonstrated that DhHP­6 significantly improved infarct volume, brain edema and neurological deficits, and reduced the percentage of TUNEL­positive cells. The levels of ROS and MDA were decreased, whereas no significant changes in the activities of SOD, CAT and GSH­Px were observed. The levels of Bax, cleaved caspase­3, and cytochrome c were downregulated, whereas the levels of Bcl­2 and p­Akt/Akt were upregulated. The results of the present study indicated that DhHP­6 may offer therapeutic potential for cerebral ischemia. The neuroprotective effects of DhHP­6 maybe mediated by its anti­oxidative properties, anti­apoptotic activities, or activation of the phosphoinositide 3­kinase/Akt survival pathway.

[Effects of cigarette, alcohol consumption and sauna on sperm morphology].

OBJECTIVE: To investigate effects of cigarette, alcohol consumption and sauna on sperm morphology. METHODS: 602 cases of male infertility were selected from our case database, who were divided into three subgroups: smoking (243) , drinking(224), sauna(135) and those without any of the above habits were taken as the corresponding controls. The sperm morphology were analyzed by automated sperm morphology analyzer(ASMA). A questionnaire was voluntarily filled out by patients in order to investigate cigarette, alcohol consumption and sauna frequency. RESULTS: The normal morphologic sperm rates in cigarette, alcohol consumption and sauna groups were lower than those in the corresponding control groups, respectively(P <0.05, P <0.001). Percentages of irregularity head sperm were higher than those in normal controls, respectively(P <0.05). CONCLUSION: Cigarette, alcohol consumption and sauna could affect sperm morphology, especially caused increasing of irregularity head sperm.