Tubular toxicity of proteinuria and the progression of chronic kidney disease.

Proteinuria is a well-established biomarker of chronic kidney disease (CKD) and a risk predictor of associated disease outcomes. Proteinuria is also a driver of CKD progression toward end-stage kidney disease. Toxic effects of filtered proteins on proximal tubular epithelial cells enhance tubular atrophy and interstitial fibrosis. The extent of protein toxicity and the underlying molecular mechanisms responsible for tubular injury during proteinuria remain unclear. Nevertheless, albumin elicits its toxic effects when degraded and reabsorbed by proximal tubular epithelial cells. Overall, healthy kidneys excrete over 1000 individual proteins, which may be potentially harmful to proximal tubular epithelial cells when filtered and/or reabsorbed in excess. Proteinuria can cause kidney damage, inflammation and fibrosis by increasing reactive oxygen species, autophagy dysfunction, lysosomal membrane permeabilization, endoplasmic reticulum stress and complement activation. Here we summarize toxic proteins reported in proteinuria and the current understanding of molecular mechanisms of toxicity of proteins on proximal tubular epithelial cells leading to CKD progression.

Investigating potential anti-proliferative activity of different statins against five cancer cell lines.

Statins have been reported to have potential anti-proliferative effects through an unknown mechanism. This study aims to investigate the anti-proliferative activities of five statins, including simvastatin, rosuvastatin, fluvastatin, atorvastatin, and pravastatin, against five different cancer cell lines; cervical epithelial carcinoma DoTc2 4510, malignant melanoma A-375, muscle Ewing's sarcoma A-673, hepatocellular carcinoma HUH-7, as well as breast cancer cells MCF-7. At 100 µM, simvastatin and atorvastatin significantly inhibited 70% of cellular proliferation. At the same concentration, rosuvastatin and fluvastatin showed about 50% of inhibition only in A-375 and A-673 cancer cells in a time- and dose-dependent manner. Of all the statin drugs used, pravastatin had the least inhibitory effect on all the cancer cell lines. Western Blot analysis showed a decrease in mTOR level, and the expression of p53 tumour suppression and BCL-2 proteins was relatively elevated compared to the untreated cells. Simvastatin and atorvastatin may inhibit cellular proliferation via BCL-2/p53, Bax/Bak, and PI3K/Akt/mTOR signalling pathways. This is the first research to evaluate the anti-cancer effects of simvastatin, rosuvastatin, fluvastatin, atorvastatin, and pravastatin against five different cell lines from distinct origins and provided a relevant comparison of their efficacies for their anti-proliferative activity.

Epidemiology of dialysis-treated end-stage renal disease patients in Kazakhstan: data from nationwide large-scale registry 2014-2018.

BACKGROUND: The epidemiology of dialysis patients has been little studied in developing countries and economies in transition. We examined the prevalence, incidence and mortality rate of dialysis patients in Kazakhstan, via aggregation and utilization of large-scale administrative healthcare data. METHODS: The registry data of 8898 patients receiving dialysis therapy between 2014 and 2018 years were extracted from the Unified National Electronic Health System (UNEHS) and linked with the national population registry of Kazakhstan. We provide descriptive statistics of demographic, comorbidity and dialysis-related characteristics. RESULTS: Among all patients undergoing maintenance dialysis for end-stage renal disease (ESRD), there were 3941 (44%) females and 4957 (56%) males. 98.7% of patients received hemodialysis and 1.3% peritoneal dialysis. The majority of the patients (63%) were ethnic Kazakhs, 18% were Russians and 19% were of other ethnicities. The prevalence and incidence rate in 2014 were 135.2 and 68.9 per million population (PMP), respectively, which were different in 2018 [350.2 and 94.9 PMP, respectively]. Overall mortality rate among dialysis patients reduced from 1667/1000 patient-years [95%Confidence Interval (CI): 1473-1886] (PY) in 2014 to 710/1000PY [95%CI: 658-767] in 2018. We observed 13% lower crude survival probability in females compared to males and in older patients compared to younger ones. Russian ethnicity had 58% higher risk of death, while other ethnicities had 34% higher risk of death compared to in those of Kazakh ethnicity. CONCLUSION: We describe for the first time in Kazakhstan an increase in the prevalence and incidence of ESRD on dialysis, while mortality rate decreased over time, during 2014-2018. We observed statistically significant lower survival probability in female dialysis patients compared to males, in older patients compared to younger ones, and in patients of Russian ethnicity compared to Kazakh.

Association of medication storage with diabetes control: A cross-sectional study from Saudi Arabia.

BACKGROUND: In addition to diet restriction and physical activity, diabetes mellitus is managed by the chronic use of medications that require appropriate storage conditions to maintain their stability and effectiveness. However, there is a lack of information regarding patients' knowledge of medication storage and practices in Saudi Arabia. Therefore, the objective of this study was to determine the diabetics' knowledge about medication storage requirements and to evaluate the impact of antidiabetic medications storage on the blood glucose levels. METHODS: This study was a cross-sectional in the form of an interviewer-guided interview using a close-ended questions. The study was conducted among patients diagnosed with diabetes at diabetic clinics of public hospitals and other diabetic specialized clinics in Hail region of Saudi Arabia, over a period of four months between January to April 2019. RESULTS: A total of 501 completed questionnaires were returned. Of the respondents, 51.5% were males and 48.5% were females. Of the total participants 52.7% never achieved normal blood glucose range, which was associated with health literacy and medication storage knowledge. Almost half of the participants stored the medication correctly and others have poor knowledge and practice of medication storage, of whom 7.8% always store their medicines in their cars. CONCLUSION: Almost half of the participants lack the knowledge of appropriate storage conditions of diabetes medications, which was shown to have a significant association with blood glucose levels.

Pharmacy Malpractice: The rate and prevalence of dispensing high-risk prescription-only medications at community pharmacies in Saudi Arabia.

OBJECTIVE: To assess the compliance of community pharmacies with the regulations that prohibit the dispensing of prescription-only medications in the absence of a physician prescription in Saudi Arabia. METHOD: A cross-sectional study was conducted in the period between October 2014 and January 2015. A list of 10 prescription-only medications were selected to be studied. 150 community pharmacies were visited across 6 major regions in Saudi Arabia to assess the prevalence of non-compliance among community pharmacies. Pharmacies were selected in random and researchers (disguised as patients) requested to purchase prescription-only medications in the absence of a prescription. Not all medications were purchased at once. Data were recorded per pharmacy, where pharmacies that approved dispense of the selected drug were scored as non-compliant and the pharmacies that rejected dispense of the selected drug were scored as compliant. Compliance rate was calculated per region per drug. Pharmacies based in governmental hospitals were visited in parallel. A total of 20 were visited. Data and statistical analysis were performed using Statistical Analyses Software (SAS 9.3). RESULTS: A total of 150 pharmacies were visited over a period of 3 months. On average, the percent approved dispense of prescription-only drugs across 6 regions in Saudi Arabia is 63% and the percent rejected dispense is 37% representing a significant non-compliance rate regarding the selected list of medications in this study. The frequency of dispense per medication across 6 major regions in Saudi Arabia is as follows: Isosorbide dinitrate (86%), Enoxaparin (82%), nitroglycerin (74%), Propranolol (73%), Verapamil (70%), Warfarin (65%), Methyldopa (64%), Ciprofloxacin (57%) and Codeine (4%). CONCLUSIONS: Non-compliance of community pharmacies with the law of pharmaceutical practice is at an alarming rate in the Kingdom of Saudi Arabia and authoritative figures must intervene to impede and combat such activities.

Comparison of different serum sample extraction methods and their suitability for mass spectrometry analysis.

Mass spectrometry has been widely used, particularly in pharmacokinetic investigations and for therapeutic drug monitoring purposes. Like any other analytical method some difficulties exist in employing mass spectrometry, mainly when it is used to test biological samples, such as to detect drug candidates in mammalian serum, which is rich in proteins, lipids and other contents that may interfere with the investigational drug. The complexity of the serum proteome presents challenges for efficient sample preparation and adequate sensitivity for mass spectrometry analysis of drugs. Enrichment procedures prior to the drug analysis are often needed and as a result, the study of serum or plasma components usually demands either methods of purification or depletion of one or more. Selection of the best combination of sample introduction method is a crucial determinant of the sensitivity and accuracy of mass spectrometry. The aim of this study was to determine the highest serum protein precipitation activity of five commonly used sample preparation methods and test their suitability for mass spectrometry. We spiked three small molecules into rabbit serum and applied different protein precipitation methods to determine their precipitation activity and applicability as a mass spectrometry introductory tool.

Anti-hepatitis B activity of isoquinoline alkaloids of plant origin.

Hepatitis B virus (HBV) is the causative agent of B-type hepatitis in humans, a vaccine-preventable disease. Despite the availability of effective vaccines, globally, 2 billion people show evidence of past or current HBV infection, of which 350 million people are persistently infected, with an estimated annual increase of 1 million. There is no cure for chronic HBV infections, which are associated with cirrhotic liver failure and with an increased risk of developing hepatocellular carcinoma. Hepatitis antiviral research has focused primarily on the development of inhibitors of viral polymerase through the use of nucleoside analogues. Therefore, there is an urgent need for the development of non-nucleoside compounds to be used as an alternative or to complement the current therapy. To address this need, 18 isoquinoline alkaloids were evaluated for their potential antiviral activity against HBV in vitro.

Highly Educated Mother's Perception of Childhood Vaccination Hesitancy in Kazakhstan: A Thematic Analysis.

Background: Vaccine hesitancy among parents directly affects the child's vaccination status since they are the legal decision-makers regarding vaccinating their children. The study aimed to describe the perceptions of highly educated Kazakhstani mothers about childhood vaccination hesitancy. Methods: The study utilized a thematic analysis to explore the mothers' perceptions. A sample of 95 participants comprehensively answered the free-text questions in an online questionnaire from January to February 2023. The analysis of the free-text responses followed a semantic thematic analysis approach. The data were coded manually. Results: From the in-depth analysis of the data, 285 initial codes were extracted. The combination of similar meanings and concept codes led to 14 sub-themes and finally yielded four significant themes: misconceptions about childhood vaccination, fear of the effect of vaccine on children, distrust of the healthcare system, and social learning factors. Conclusion: The perceptions of Kazakh mothers about childhood vaccination hesitancy may lead to behaviors of delaying and refusing some or all childhood vaccines. Therefore, motivational and educational strategies can be used by healthcare providers to instill trust in parents about childhood vaccines and their safety and effectiveness.

Defining and unpacking the core concepts of pharmacology: A global initiative.

BACKGROUND AND PURPOSE: Development of core concepts in disciplines such as biochemistry, microbiology and physiology have transformed teaching. They provide the foundation for the development of teaching resources for global educators, as well as valid and reliable approaches to assessment. An international research consensus recently identified 25 core concepts of pharmacology. The current study aimed to define and unpack these concepts. EXPERIMENTAL APPROACH: A two-phase, iterative approach, involving 60 international pharmacology education experts, was used. The first phase involved drafting definitions for core concepts and identifying key sub-concepts via a series of online meetings and asynchronous work. These were refined in the second phase, through a 2-day hybrid workshop followed by a further series of online meetings and asynchronous work. KEY RESULTS: The project produced consensus definitions for a final list of 24 core concepts and 103 sub-concepts of pharmacology. The iterative, discursive methodology resulted in modification of concepts from the original study, including change of 'drug-receptor interaction' to 'drug-target interaction' and the change of the core concept 'agonists and antagonists' to sub-concepts of drug-target interaction. CONCLUSIONS AND IMPLICATIONS: Definitions and sub-concepts of 24 core concepts provide an evidence-based foundation for pharmacology curricula development and evaluation. The next steps for this project include the development of a concept inventory to assess acquisition of concepts, as well as the development of case studies and educational resources to support teaching by the global pharmacology community, and student learning of the most critical and fundamental concepts of the discipline.

The impact of cellular environment on in vitro drug screening.

There are various reasons for drug failure in the developmental stage including toxicity, adverse effects and inefficacy. This is likely due to the differences in drug behavior between a simple and controlled cell culture system to that of a more complex whole organism environment. While the use of human phenotypical cells relevant to the condition may provide more accurate screening results, they are susceptible to producing false positives as cells are continuously influenced by constant chemical and physical interaction with the surrounding microenvironment. Therefore, several microenvironmental and pharmacomechanical aspects must be factored in during tissue culture drug screening.

Drug discovery is a lengthy process that goes through several preclinical and clinical testing stages. One of the earliest stages in preclinical testing involves testing new drug using isolated cells. This system is an important tool in research and a commonly used technique in drug testing. However, a number of subtle, but important issues appear to affect its results. Therefore, in this review, we attempt to address some of the important issues that could lead to false positive or negative hits.

The antiproliferative potential and mechanism of action of metformin in MCF-7 cells.

Aim: The current study aimed to investigate the potential antiproliferative activity of metformin, the effective concentration range, and the mechanism of action. Materials & methods: Human breast cancer cells, MCF-7 were treated with a serial dilution of metformin (10-150 µM) for 24 and 48 h. Potential antiproliferative activity of metformin and its ability in inducing cellular apoptosis and autophagy were also investigated. Results: Metformin inhibited MCF-7 proliferation in a concentration and time dependent manner, with 80 µM as the most effective concentration. Compared with nontreated cells, metformin induced significant levels of autophagy and apoptosis, which were confirmed by the reduction of mTOR and BCL-2 protein expression. Conclusion: The study confirms the antiproliferative activity of metformin, which may likely occur through AMPK signaling pathway.

The antidiabetic drug, metformin is tested in this work for its possible ability to inhibit the growth of breast cancer cells. Using different concentrations of the drug over different time points, the results showed that the drug was able to inhibit cancer growth through different mechanisms. The results also showed that the drug inhibits cancer growth by stimulating program cell death (apoptosis), as well as autophagy, where the cell breaks old and abnormal cellular substances.

The Impact of Tetracycline Pollution on the Aquatic Environment and Removal Strategies.

Antibacterial drugs are among the most commonly used medications in the world. Tetracycline is a widely used antibiotic for human and animal therapy due to its broad-spectrum activity, high effectiveness, and reasonable cost. The indications for treatment with tetracycline include pneumonia, bone and joint infections, infectious disorders of the skin, sexually transmitted and gastrointestinal infections. However, tetracycline has become a serious threat to the environment because of its overuse by humans and veterinarians and weak ability to degrade. Tetracycline is capable of accumulating along the food chain, causing toxicity to the microbial community, encouraging the development and spread of antibiotic resistance, creating threats to drinking and irrigation water, and disrupting microbial flora in the human intestine. It is essential to address the negative impact of tetracycline on the environment, as it causes ecological imbalance. Ineffective wastewater systems are among the main reasons for the increased antibiotic concentrations in aquatic sources. It is possible to degrade tetracycline by breaking it down into small molecules with less harmful or nonhazardous effects. A range of methods for physical, chemical, and biological degradation exists. The review will discuss the negative effects of tetracycline consumption on the aquatic environment and describe available removal methods.

Blueberry and cranberry extracts mitigate CCL4-induced liver damage, suppressing liver fibrosis, inflammation and oxidative stress.

The current study aims to evaluate potential hepatoprotective effect of lingonberry, cranberry and blueberry polyphenols on carbon tetrachloride (CCL-4)-induced acute and subacute liver injury in rats. A total of 55 male Wistar rats, divided into six experimental and control groups. With the exception of the negative control group, all groups received an intraperitoneal injection of CCl-4, twice a week for 14 days. An extract of lingonberry, cranberry, blueberry polyphenols and the positive control, silymarin were administered daily via intragastric route, for 14 consecutive days. The untreated control group showed characteristic of classical oxidative stress-mediated liver damage with vacuolization of the hepatocyte cytoplasm, infiltration by immune cells and proliferation of collagen fibers, decrease in body weight and increase in liver weight; increased levels of AST and ALT in serum, an increased lipid peroxidation in the liver. However, the use of cranberry and blueberry polyphenols significantly suppressed liver damage, exerting an effect comparable to the hepatoprotective effect of the positive control. The extracts prevented and reduced inflammatory liver damage by reducing IL-6, TNF-α and IFN-γ levels. In conclusion, blueberry and cranberry extracts have a protective effect against acute and subacute CCl4-induced hepatotoxicity in rats.

Drug Repurposing of Generic Drugs: Challenges and the Potential Role for Government.

Drug repurposing is the process of identifying a new use for an existing drug or active substance in an indication outside the scope of the original indication. Drug repurposing has important advantages including reduced development time and costs, and potentially large societal healthcare cost savings. However, current generic drug repurposing research faces a number of challenges in obtaining research funds. Furthermore, regardless of the success of a repurposing trial, commercial parties often lack interest in pursuing marketing authorisation for financial reasons, and academic researchers lack the knowledge, time and funding. Therefore, the new indication of a repurposed drug often does not make it 'on label'. We propose a large increase in public funding for generic drug repurposing research, including funds for the marketing authorisation process when a trial is successful, and a reduction in the regulatory burden of the marketing authorisation process for repurposed generic drugs.

The Effect of Different Glucose Concentrations on the Antiproliferative Activity of Metformin in MCF-7 Breast Cancer Cells.

The glucose-lowering drug metformin has been reported to have anticancer properties through unknown mechanisms. Other unknown factors that may influence its anticancer potential include the glycemic status of the patient. Therefore, the objective of this study is to determine the effect of different glucose environments on the antiproliferative potency and the cellular mechanism of action of metformin. Human breast cancer cells, MCF-7, were incubated in low, normal, elevated, and high glucose environments and treated with metformin. The antiproliferative potential of metformin and its effect on protein expression as well as its ability to induce cellular apoptosis and autophagy under different glucose environments, were determined using different molecular techniques. Metformin significantly inhibited cellular proliferation in a time- and glucose-concentration-dependent manner. In comparison to elevated glucose, low normal glucose alone induced a significant level of autophagy that was further increased in the presence of metformin. While glucose concentration did not appear to have an effect on the antiproliferative potency of metformin, the cellular basis of action was shown to be glucose-dependent. The antiproliferative mechanism of action of metformin in elevated and low normal glucose environments is mTOR-dependent, whereas, in the high glucose environment, the antiproliferative mechanism is independent of mTOR. This is the first study to report that both the antiproliferative potency and the cellular mechanism of action aredependent on the concentration of glucose.

Cleavage of endometrial α-integrins into their functional forms is mediated by proprotein convertase 5/6.

BACKGROUND: Proprotein convertases (PCs) post-translationally activate a large number of protein precursors through limited cleavage. PC5/6 (PC6) in the human endometrium is tightly regulated during receptivity for embryo implantation. Integrins are transmembrane glycoproteins, some of which play an important role in the adhesive interactions between the trophoblast (blastocyst) and uterine epithelium at implantation. Integrins require PC cleavage for post-translational modification. We hypothesize that pro-integrin-αs in the endometrial epithelium are post-translationally cleaved by PC6 into functional subunits for the binding of blastocyst and adhesion of extracellular matrix proteins. METHODS AND RESULTS: We first used the endometrial epithelial cell line, HEC1A, into which siRNA specific to human PC6 (PC6-siRNA) or scrambled sequence (control) was stably transfected. The specific knockdown was confirmed by real-time RT-PCR. PC6-siRNA cells reduced their capacity to attach to trophoblast spheroids and bind to fibronectin compared with control. Knockdown of PC6 decreased cell surface presentation of functional integrins-α1, α2, α5, αV and αVß5. Western blot analysis demonstrated that PC6 was responsible for the post-translational cleavage of pro-integrin-α5 and integrin-αV into their heavy and light chains in HEC1A cells. We then isolated primary human endometrial epithelial cells and validated that PC6 mediated the post-translational cleavage of integrin-αs in these cells. CONCLUSIONS: This study implicates PC6 as a key regulatory protein essential for the attachment of the blastocyst to the endometrial epithelium through the processing of pro-integrin-αs. Compromised PC6 action reduces the post-translational modification of integrin-αs, thus compromising implantation.

Antiproliferative and cytotoxic activity of Geraniaceae plant extracts against five tumor cell lines.

AIM: To determine the antiproliferative and cytotoxic activities of Geranium and Erodium species against human cancer and noncancer cell lines, respectively. METHODS: Twenty-one species of Geranium and Erodium were extracted and screened against cancerous and noncancerous human cell lines. RESULTS: In a dose-response manner, G. glaberrimum, G. asphodeloides, E. brandianum and E. leucanthum were able, with variable potency, to inhibit cellular proliferation. Except for E. brandianum, all extracts induced cellular autophagy in tumor cells with similar levels to that of rapamycin; but, only E. brandianum induced cellular apoptosis, likely through Bcl2 and BAX protein expressions. DISCUSSION: This is the first study to report the potential antiproliferative effects of ethanol extracts of several Geraniaceae species.

Therapeutic Potential of Metabolites from Lactobacillus rhamnosus and Mare's Milk in the Treatment of Dysbiosis.

Ulcerative colitis is an inflammatory bowel disease that forms ulcerations in the mucous membrane of the colon and rectum, in which gut microbiota plays a pivotal role in its pathogenesis. Agents modulating microbial dysbiosis caused by colitis can help in the remission of this disease. The current study describes the potential therapeutic effects of active metabolites from Lactobacillus rhamnosus and mare's milk which have potential therapeutic values on the intestinal microbiota and proinflammatory cytokines. The analysis of the V1-V3 16S rDNA site revealed significant changes in the intestinal microbiome composition before and after treatment in the treated group compared to the positive control group that was treated with 5-aminosalicylic acid (5-ASA). So the effect of the study product on dextran sulfate sodium-induced dysbiosis was shown to be more potent than the positive control, 5-ASA. The level of proinflammatory cytokines also decreased under the influence of a biological product.

Viral entry inhibitors targeted to the membrane site of action.

The fusion of enveloped viruses with the host cell is driven by specialized fusion proteins to initiate infection. The "class I" fusion proteins harbor two regions, typically two heptad repeat (HR) domains, which are central to the complex conformational changes leading to fusion: the first heptad repeat (HRN) is adjacent to the fusion peptide, while the second (HRC) immediately precedes the transmembrane domain. Peptides derived from the HR regions can inhibit fusion, and one HR peptide, T20 (enfuvirtide), is in clinical use for HIV-1. For paramyxoviruses, the activities of two membrane proteins, the receptor-binding protein (hemagglutinin-neuraminidase [HN] or G) and the fusion protein (F), initiate viral entry. The binding of HN or G to its receptor on a target cell triggers the activation of F, which then inserts into the target cell and mediates the membrane fusion that initiates infection. We have shown that for paramyxoviruses, the inhibitory efficacy of HR peptides is inversely proportional to the rate of F activation. For HIV-1, the antiviral potency of an HRC-derived peptide can be dramatically increased by targeting it to the membrane microdomains where fusion occurs, via the addition of a cholesterol group. We report here that for three paramyxoviruses-human parainfluenza virus type 3 (HPIV3), a major cause of lower respiratory tract diseases in infants, and the emerging zoonotic viruses Hendra virus (HeV) and Nipah virus (NiV), which cause lethal central nervous system diseases-the addition of cholesterol to a paramyxovirus HRC-derived peptide increased antiviral potency by 2 log units. Our data suggest that this enhanced activity is indeed the result of the targeting of the peptide to the plasma membrane, where fusion occurs. The cholesterol-tagged peptides on the cell surface create a protective antiviral shield, target the F protein directly at its site of action, and expand the potential utility of inhibitory peptides for paramyxoviruses.

PTOV1 is associated with UCH-L1 and in response to estrogen stimuli during the mouse oocyte development.

To investigate the biological significance of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) involvement in oocyte maturation, we screened for proteins that bound to UCH-L1 in mouse ovaries, and we found that the prostate tumor overexpressed-1 (PTOV1) protein was able to bind to UCH-L1. PTOV1 is highly expressed in prostate cancers and considered as a potential marker for carcinogenesis and the progress of prostate cancer. It was reported that PTOV1 plays an important role in cell cycle regulation, but its role in mammalian oocyte development and meiosis is still unclear. In this paper, it was found that the expression levels of PTOV1 in mouse ovaries progressively increased from prepubescence to adulthood. And we found by immunohistochemistry that PTOV1 spreaded in both the cytoplasm and nuclei of oocytes during prepuberty, but in normal adult mouse oocytes, it concentrated not only in nuclei but also on the plasma membrane, though in some oocytes with abnormal shapes, PTOV1 did not display the typical distribution patterns. In granulosa cells, however, it was found to locate in the cytoplasm at all the selected ages. In postnatal mouse ovaries (28 days), estradiol treatment induced the adult-specific distribution pattern of PTOV1 in oocytes. In addition, UCH-L1 was shown to be associated with CDK1, which participated in the regulation of cell cycle and oocyte maturation. Therefore, we propose that the distribution changes of PTOV1 are age-dependent, and significant for mouse oocyte development and maturation. Moreover, the discovery that PTOV1 is associated with UCH-L1 in mouse oocytes supports the explanations for that UCH-L1 is involved in oocyte development and maturation, especially under the regulation of estrogen.