From whole genomes to probiotic candidates: A study of potential lactobacilli strains selection for vaginitis treatment.

Vaginitis, characterized by pathogenic invasion and a deficiency in beneficial lactobacilli, has recognized lactobacilli supplementation as a novel therapeutic strategy. However, due to individual differences in vaginal microbiota, identifying universally effective Lactobacillus strains is challenging. Traditional methodologies for probiotic selection, which heavily depend on extensive in vitro experiments, are both time-intensive and laborious. The aim of this study was to pinpoint possible vaginal probiotic candidates based on whole-genome screening. We sequenced the genomes of 98 previously isolated Lactobacillus strains, annotating their genes involved in probiotic metabolite biosynthesis, adherence, acid/bile tolerance, and antibiotic resistance. A scoring system was used to assess the strains based on their genomic profiles. The highest-scoring strains underwent further in vitro evaluation. Consequently, two strains, Lactobacillus crispatus LG55-27 and Lactobacillus gasseri TM13-16, displayed an outstanding ability to produce d-lactate and adhere to human vaginal epithelial cells. They also showed higher antimicrobial activity against Gardnerella vaginalis, Escherichia coli, Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa compared to reference Lactobacillus strains. Their resilience to acid and bile environments highlights the potential for oral supplementation. Oral and vaginal administration of these two strains were tested in a bacterial vaginosis (BV) rat model at various doses. Results indicated that combined vaginal administration of these strains at 1 × 106 CFU/day significantly mitigated BV in rats. This research offers a probiotic dosage guideline for vaginitis therapy, underscoring an efficient screening process for probiotics using genome sequencing, in vitro testing, and in vivo BV model experimentation.

Genomic and functional diversity of cultivated Bifidobacterium from human gut microbiota.

The genus Bifidobacterium widely exists in human gut and has been increasingly used as the adjuvant probiotics for the prevention and treatment of diseases. However, the functional differences of Bifidobacterium genomes from different regions of the world remain unclear. We here describe an extensive study on the genomic characteristics and function annotations of 1512 genomes (clustered to 849 non-redundant genomes) of Bifidobacterium cultured from human gut. The distribution of some carbohydrate-active enzymes varied among different Bifidobacterium species and continents. More than 36% of the genomes of B. pseudocatenulatum harbored biosynthetic gene clusters of lanthipeptide-class-iv. 99.76% of the cultivated genomes of Bifidobacterium harbored genes of bile salt hydrolase. Most genomes of B. adolescentis, and all genomes of B. dentium harbored genes involved in gamma-aminobutyric acid synthesis. B. longum subsp. infantis were characterized harboring most genes related to human milk oligosaccharide utilization. Significant differences between the distribution of antibiotic resistance genes among different species and continents revealed the importance to use antibiotics precisely in the clinical treatment. Phages infecting Bifidobacterium and horizontal gene transfers occurring in genomes of Bifidobacterium were dependent on species and region sources, and might help Bifidobacterium adapt to the environment. In addition, the distribution of Bifidobacterium in human gut was found varied from different regions of the world. This study represents a comprehensive view of characteristics and functions of genomes of cultivated Bifidobacterium from human gut, and enables clinical advances in the future.

The impact of contrast retention on thrombus formation risks in patients with atrial fibrillation: A numerical study.

Background: Contrast retention (CR) is an important predictor of left atrial appendage thrombus (LAAT) and stroke in patients with non-valvular atrial fibrillation (AF). We sought to explore the underlying mechanisms of CR using computational fluid dynamic (CFD) simulations. Methods: A total of 12 patients with AF who underwent both cardiac computed tomography angiography (CTA) and transesophageal echocardiography (TEE) before left atrial appendage occlusion (LAAO) were included in the study. The patients were allocated into the CR group or non-CR group based on left atrial appendage (LAA) angiography. Patient-specific models were reconstructed to evaluate time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and endothelial cell activation potential (ECAP). Additionally, the incidence of thrombosis was predicted using residence time (RT) at different time-points. Results: TAWSS was lower [median (Interquartile Range) 0.27 (0.19-0.47) vs 1.35 (0.92-1.79), p < 0.001] in LAA compared to left atrium. In contrast, RRT [1438 (409.70-13869) vs 2.23 (1.81-3.14), p < 0.001] and ECAP [122.70 (30.01-625.70) vs 0.19 (0.16-0.27), p < 0.001)] was higher in the LAA. The patients in the CR group had significantly higher RRT [(mean ± SD) 16274 ± 11797 vs 639.70 ± 595.20, p = 0.009] and ECAP [610.80 ± 365.30 vs 54.26 ± 54.38, p = 0.004] in the LAA compared to the non-CR group. Additionally, patients with CR had a wider range of thrombus-prone regions [0.44(0.27-0.66)% vs 0.05(0.03-0.27)%, p = 0.009] at the end of the 15th cardiac cycle. Conclusions: These findings suggest that CR might be an indicator of high-risk thrombus formation in the LAA. And CT-based CFD simulation may be a feasible substitute for the evaluation of LAA thrombotic risk in patients with AF, especially in patients with CR.

Knowledge, attitude, and practice toward photoaging in the Chinese population: a cross-sectional study.

To investigate the knowledge, attitude, and practice (KAP) of photoaging in the Chinese population. This web-based cross-sectional study was conducted between January 2023 and March 2023 among the Chinese population aged 18-80 years old. Participants' knowledge, attitude, and practice toward photoaging were collected through a self-administered questionnaire. A total of 830 questionnaires were collected, with 826 valid questionnaires and an efficiency rate of 99.52%. There were 274 (33.17%) males and 532 (64.41%) aged 31-51 years old. The average knowledge, attitude, and practice scores were 7 (4, 9) (possible range 0-12), 31.5 (28, 34) (possible range 8-40), and 33 (24, 42) (possible range 11-55), respectively, indicating poor knowledge, good attitude, and moderate practice. Spearman correlation analysis showed that knowledge was negatively correlated with attitude (r = - 0.111, P < 0.05) and practice (r = - 0.113, P < 0.05), and attitude was positively correlated with practice (r = 0.992, P < 0.05). The multivariable linear regression model showed that for each point increase in attitude score, the practice score increased by 2.96 points (ß = 2.96, 95% CI 2.91-3.01, P < 0.001). The Chinese population has poor knowledge, good attitude, and moderate practice toward photoaging. A good attitude toward photoaging would lead to good practice, and more outreach and education for the Chinese population might be needed.

Design-rules for stapled peptides with in vivo activity and their application to Mdm2/X antagonists.

Although stapled α-helical peptides can address challenging targets, their advancement is impeded by poor understandings for making them cell permeable while avoiding off-target toxicities. By synthesizing >350 molecules, we present workflows for identifying stapled peptides against Mdm2(X) with in vivo activity and no off-target effects. Key insights include a clear correlation between lipophilicity and permeability, removal of positive charge to avoid off-target toxicities, judicious anionic residue placement to enhance solubility/behavior, optimization of C-terminal length/helicity to enhance potency, and optimization of staple type/number to avoid polypharmacology. Workflow application gives peptides with >292x improved cell proliferation potencies and no off-target cell proliferation effects ( > 3800x on-target index). Application of these 'design rules' to a distinct Mdm2(X) peptide series improves ( > 150x) cellular potencies and removes off-target toxicities. The outlined workflow should facilitate therapeutic impacts, especially for those targets such as Mdm2(X) that have hydrophobic interfaces and are targetable with a helical motif.

The impact of the COVID-19 pandemic on SLE.

Little is known about the association between coronavirus disease 2019 (COVID-19) and autoimmune diseases, especially in the case of systemic lupus erythematosus (SLE). SLE patients met with many questions during the pandemic in COVID-19, such as how to minimize risk of infection, the complex pathological features and cytokine profiles, diagnosis and treatment, rational choice of drugs and vaccine, good nursing, psychological supervision, and so on. In this study, we review and discuss the multifaceted effects of the COVID-19 pandemic on patients living with SLE using the available literature. Cross-talk in implicated inflammatory pathways/mechanisms exists between SLE and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and SARS-CoV-2 displays similar clinical characteristics and immuno-inflammatory responses to SLE. Current epidemiological data inadequately assess the risk and severity of COVID-19 infection in patients with SLE. More evidence has shown that hydroxychloroquine and chloroquine cannot prevent COVID-19. During the pandemic, patients with SLE had a higher rate of hospitalization. Vaccination helps to reduce the risk of infection. Several therapies for patients with SLE infected with COVID-19 are discussed. The cases in the study can provide meaningful information for clinical diagnosis and management. Our main aim is to help preventing infection and highlight treatment options for patients with SLE infected with COVID-19.

Safety assessment of potential probiotic Lactobacillus acidophilus AM13-1 with high cholesterol-lowering capability isolated from human gut.

An important risk factor for cardiovascular disease is dyslipidemia, especially abnormal cholesterol levels. The relation between probiotics and cholesterol-lowering capability has been extensively studied. Lactobacillus acidophilus plays a significant role in affecting host health, and produces multitudinous metabolites, which have prohibitory functions against pathogenic microorganisms. In this study, we identified a cholesterol-lowering strain AM13-1, isolated from a fecal sample obtained from a healthy adult male, and performed comprehensive function analysis by whole-genome analysis and in vitro experiments. Genome analyses of L. acidophilus AM13-1 revealed that carbohydrate and amino acid transport, metabolism, translation, ribosomal structure, and biogenesis are abundant categories of functional genes. No virulence factors or toxin genes with experimentally verified were found in the genome of strain AM13-1. Besides, plenty of probiotic-related genes were predicted from the L. acidophilus AM13-1 genome, such as cbh, atpA-D, and dltD, with functions related to cholesterol-lowering and acid resistance. And strain AM13-1 showed high-efficiency of bile salt hydrolase activity and the capacity for removing cholesterol with efficiency rates of 70%. These function properties indicate that strain AM13-1 can be considered as a probiotic candidate for use in food and health care products.

Fractional laser combined with 5-Aminolevulinic acid photodynamic therapy for the treatment of Cutaneous Rosai-Dorfman Disease: A case report.

Rosai-Dorfman disease(RDD) is a rare benign histiocytic proliferative disorder. Cutaneous Rosai-Dorfman disease(CRDD)is a rare variant of RDD with lesions localized to the skin. We report a case of patients with CRDD who was refractory to methotrexate, thalidomide, cyclosporine, glucocorticoid for local injection and external use, but resolved with fractional laser combined with 5-aminolevulinic acid photodynamic therapy (ALA-PDT). We believe that fractional laser technology combined with ALA-PDT for CRDD is a minimally invasive, effective and satisfactory treatment.

A high-throughput microfluidic mechanoporation platform to enable intracellular delivery of cyclic peptides in cell-based assays.

Cyclic peptides are poised to target historically difficult to drug intracellular protein-protein interactions, however, their general cell impermeability poses a challenge for characterizing function. Recent advances in microfluidics have enabled permeabilization of the cytoplasmic membrane by physical cell deformation (i.e., mechanoporation), resulting in intracellular delivery of impermeable macromolecules in vector- and electrophoretic-free approaches. However, the number of payloads (e.g., peptides) and/or concentrations delivered via microfluidic mechanoporation is limited by having to pre-mix cells and payloads, a manually intensive process. In this work, we show that cells are momentarily permeable (t 1/2 = 1.1-2.8 min) after microfluidic vortex shedding (µVS) and that lower molecular weight macromolecules can be cytosolically delivered upon immediate exposure after cells are processed/permeabilized. To increase the ability to screen peptides, we built a system, dispensing-microfluidic vortex shedding (DµVS), that integrates a µVS chip with inline microplate-based dispensing. To do so, we synced an electronic pressure regulator, flow sensor, on/off dispense valve, and an x-y motion platform in a software-driven feedback loop. Using this system, we were able to deliver low microliter-scale volumes of transiently mechanoporated cells to hundreds of wells on microtiter plates in just several minutes (e.g., 96-well plate filled in <2.5 min). We validated the delivery of an impermeable peptide directed at MDM2, a negative regulator of the tumor suppressor p53, using a click chemistry- and NanoBRET-based cell permeability assay in 96-well format, with robust delivery across the full plate. Furthermore, we demonstrated that DµVS could be used to identify functional, low micromolar, cellular activity of otherwise cell-inactive MDM2-binding peptides using a p53 reporter cell assay in 96- and 384-well format. Overall, DµVS can be combined with downstream cell assays to investigate intracellular target engagement in a high-throughput manner, both for improving structure-activity relationship efforts and for early proof-of-biology of non-optimized peptide (or potentially other macromolecular) tools.

Orally administrated Lactobacillus gasseri TM13 and Lactobacillus crispatus LG55 can restore the vaginal health of patients recovering from bacterial vaginosis.

Bacterial vaginosis (BV) is a common infection of the lower genital tract with a vaginal microbiome dysbiosis caused by decreasing of lactobacilli. Previous studies suggested that supplementation with live Lactobacillus may benefit the recovery of BV, however, the outcomes vary in people from different regions. Herein, we aim to evaluate the effectiveness of oral Chinese-origin Lactobacillus with adjuvant metronidazole (MET) on treating Chinese BV patients. In total, 67 Chinese women with BV were enrolled in this parallel controlled trial and randomly assigned to two study groups: a control group treated with MET vaginal suppositories for 7 days and a probiotic group treated with oral Lactobacillus gasseri TM13 and Lactobacillus crispatus LG55 as an adjuvant to MET for 30 days. By comparing the participants with Nugent Scores ≥ 7 and < 7 on days 14, 30, and 90, we found that oral administration of probiotics did not improve BV cure rates (72.73% and 84.00% at day 14, 57.14% and 60.00% at day 30, 32.14% and 48.39% at day 90 for probiotic and control group respectively). However, the probiotics were effective in restoring vaginal health after cure by showing higher proportion of participants with Nugent Scores < 4 in the probiotic group compared to the control group (87.50% and 71.43% on day 14, 93.75% and 88.89% on day 30, and 77.78% and 66.67% on day 90). The relative abundance of the probiotic strains was significantly increased in the intestinal microbiome of the probiotic group compared to the control group at day 14, but no significance was detected after 30 and 90 days. Also, the probiotics were not detected in vaginal microbiome, suggesting that L. gasseri TM13 and L. crispatus LG55 mainly acted through the intestine. A higher abundance of Prevotella timonensis at baseline was significantly associated with long-term cure failure of BV and greatly contributed to the enrichment of the lipid IVA synthesis pathway, which could aggravate inflammation response. To sum up, L. gasseri TM13 and L. crispatus LG55 can restore the vaginal health of patients recovering from BV, and individualized intervention mode should be developed to restore the vaginal health of patients recovering from BV. Clinical trial registration: https://classic.clinicaltrials.gov/ct2/show/, identifier NCT04771728.

Ultrasound-Guided Brachial Plexus Block by Costoclavicular Space Approach: A Narrative Review.

In recent years, ultrasound-guided costoclavicular brachial plexus block (CCB) has gained attention as a novel approach for brachial plexus nerve block. Human anatomy studies have identified the costoclavicular space as the area between the midpoint of the clavicle and the first rib. This space accommodates the brachial plexus, axillary arteries, and veins. Its superficial and fixed position makes it a promising option for infraclavicular brachial plexus blockage, providing a safe and reliable analgesic effect. CCB combines the benefits of real-time ultrasound visualization of the nerve block needle, avoidance of peripheral blood vessels, and targeted delivery of local anesthetics to the nerve. Consequently, it significantly reduces the associated complications of other classical approaches such as interscalene brachial plexus block (ISB), supraclavicular brachial plexus block (SCB), lateral sagittal infraclavicular brachial plexus block (LS-ICB), and axillary brachial plexus block. These complications include phrenic paralysis, incomplete brachial plexus block, and pneumothorax. This narrative review examines the literature on brachial plexus block in the costoclavicular space, discussing the anatomical position, the procedure, clinical indications, choice of local anesthetic concentration and volume, and continuous nerve block of CCB. The aim is to provide a basis for future clinical practice and enhanced safety.

Probiotic characteristics of Lactobacillus gasseri TF08-1: A cholesterol-lowering bacterium, isolated from human gut.

Lactobacillus contribute to maintain the human healthy and use for nutritional additives as probiotics. In this study, a cholesterol-lowering bacterium, Lactobacillus gasseri TF08-1, was isolated from the feces of a healthy adolescent, and its probiotic potentials were evaluated through genomic mining and in vitro test. The assembled draft genome comprised of 1,974,590 bp and was predicted total of 1,940 CDSs. The annotation of the genome revealed that L. gasseri TF08-1 harbored abundant categories of functional genes in metabolic and information processing. Moreover, strain TF08-1 has capacity to utilize D-Glucose, Sucrose, D-Maltose, Salicin, D-Xylose, D-Cellobiose, D-Mannose, and D-Trehalose, as the carbon source. The safety assessment showed strain TF08-1 contained few antibiotic resistance genes and virulence factors and was only resistant to 2 antibiotics detected by antimicrobial susceptibility test. A high bile salt hydrolase activity was found and a cholesterol-reducing effect was determined in vitro, which the result showed a remarkable cholesterol removal capability of L. gasseri TF08-1 with an efficiency of 84.40 %. This study demonstrated that the strain showed great capability of exopolysaccharide production, and tolerance to acid and bile salt. Therefore, these results indicate that L. gasseri TF08-1 can be considered as a safe candidate for probiotic, especially its potential in biotherapeutic for metabolic diseases.

The effect of subaxillary endoscopic surgery without air inflation on the degree of pain and the incidence of complications in athletic patients with unilateral thyroid cancer

Objective: To investigate the effect of subaxillary inflatable endoscopic surgery on the degree of pain and the incidence of complications in athletic patients with unilateral thyroid cancer. Methods: Sixty athletic patients with unilateral thyroid carcinnma (TC) accepted treatment in the hospital from January 2020 to December 2021 were chosen to be the object of the study. Adapting the means of random number table, they were split into 30 cases both in the control group and in the observation group. The control group were treated with traditional open surgery, and the observation group took the remedy with non-inflatable endoscopic surgery through axillary approach. The operation time, intraoperative bleeding, postoperative drainage volume, incision length and inpatient days; Satisfaction with the cosmetic effect of incision; Visual analogue scale (VAS); The occurrence of complications were contrasted within two groups. Results: Compare to the control group, the operation time, as well as postoperative drainage volume in the observation group increased fairly, and the amount of intraoperative bleeding, incision length and hospital stay considerably declined (P < 0.05); In contrast to the control group (56.67%), the satisfaction of the observation one with the cosmetic effect of incision (90.00%) was significantly higher (P < 0.05); In contrast to the control group, the VAS score of the observation group cut down considerably at 24h and 48h after operation (P < 0.05); In contrast with the control group (43.33%), the incidence of complications in the observation group (16.67%) decreased considerably(P < 0.05). (AU)

Does microneedle fractional radiofrequency system inactivate botulinum toxin type A?

BACKGROUND: The combination of botulinum toxin type A (BoNT/A) and energy equipment have been widely used in the clinic. AIMS: To determine whether the energy of microneedle fractional radiofrequency (MFR) affects the efficacy of BoNT/A and to provide an optimal strategy for the energy device in combination with BoNT/A in the clinic. METHODS: First, a total of 45 females with moderate-to-severe periorbital crow's feet wrinkles were enrolled and divided into three groups according to different treatment methods and intervals, including BoNT/A injection alone, BoNT/A injected immediately after MFR treatment and BoNT/A injected 7 days after MFR treatment. The photographs were compared before treatment and 4 weeks after treatment. Then, the mouse models were established by combining MFR with BoNT/A at different intervals, to evaluate muscle strength, muscle mass, muscle nutritional markers, and important cytokines levels. RESULTS: All patients in each group had high satisfaction. The MFR + BoNT/A (immediately) group could improve dynamic wrinkles, but the others had more significant efficacy (p < 0.05). The results of mouse models showed that all BoNT/A groups induced different degrees of muscle paralysis in vivo, but the paralytic effect induced by the BoNT/A group, MFR + BoNT/A (interval of 3-day) group, and MFR + BoNT/A (interval of 7-day) group were higher than others and the expression levels of muscle nutritional markers in NMJ tissues were significantly upregulated. CONCLUSION: MFR has a certain reduction effect on the activity of BoNT/A, and this reduction effect would last for 3 days after MFR treatment.

Corrigendum: Dietary fiber and probiotics based on gut microbiota targeting for functional constipation in children with cerebral palsy.

[This corrects the article DOI: 10.3389/fped.2022.1001789.].

Dietary fiber and probiotics based on gut microbiota targeting for functional constipation in children with cerebral palsy.

Gastrointestinal (GI) disorders are very common among children with cerebral palsy. Gut microbiota has been confirmed to maintain normal GI physiological function and further contributed to cerebral palsy through the gut-brain axis. Our study was to investigate the effect of dietary fiber combined with probiotics on functional constipated children with cerebral palsy. In total, 35 patient children were enrolled and divided into general diet group (n = 14) and liquid diet group (n = 21). All the participants received Compound Dietary Fiber (CDF) for 1 month and lactic acid-producing and butyric acid-producing probiotics for 6 months. After a 1-month intervention, the frequency of spontaneous and manual defecation, and Bristol score were all significantly improved (P < 0.001). The α-diversity of the gut microbiota was significantly increased after a 1-month intervention (P < 0.05), with a higher abundance of butyric acid-producing bacteria and a lower abundance of opportunistic pathogens (P < 0.05, FDR < 0.05). However, the impersistent effect of the 6-month intervention suggested the insufficient impact of intaking probiotics alone and the short duration of CDF intervention. Moreover, although the intervention had affected the constipation symptoms equally in cerebral palsy children with a general diet and liquid diet, the general diet group showed a greater and more durable change in gut microbiota and clinical phenotypes after intervention than the liquid diet group, which indicated that longer intervention time should be considered for liquid diet children. This study not only illustrated that supplementation of dietary fiber combined with probiotics can improve functional constipation in children with cerebral palsy, but also provides guidance for optimal intervention strategy for future studies, which will further benefit cerebral palsy children. Clinical trial registration: http://www.chictr.org.cn/showproj.aspx?proj=46902, identifier: ChiCTR1900028257.

Differential Diagnosis of Rosacea Using Machine Learning and Dermoscopy.

Introduction: Rosacea is a common chronic inflammatory disease occurring on the face, whose diagnosis is mainly based on symptoms and physical signs. Due to some overlap in symptoms and signs with other inflammatory skin diseases, young and inexperienced doctors often make misdiagnoses and missed diagnoses in clinical practices. We analyze the results of skin physiology and dermatoscopy using machine learning method and identify the characteristics of acne rosacea, which differentiate it from other common facial inflammatory skin diseases so as to improve the accuracy of clinical and differential diagnosis of rosacea. Methods: A total of 495 patients who were jointly diagnosed by two experienced doctors were included. Basic data, clinical symptoms, physiological skin detection, and dermatoscopy results were collected, and the clinical characteristics of rosacea and other common facial inflammatory diseases were summarized according to the descriptive analysis results. The model was established using a machine learning method and compared with the judgment results of young and inexperienced doctors to verify whether the model can improve the accuracy of clinical diagnosis and differential diagnosis of rosacea. Results: The proportion of yellow and red halos, vascular polygons, as well as follicular pustules, showed by dermatoscopy, and the melanin index in physiological skin detection revealed statistical significance in differentiating rosacea and other common facial inflammatory diseases (all P < 0.01). After adopting the machine learning, we found that GBM (Gradient Boosting Machine) algorithm was the best, and the error rate of this model in the validation set was 5.48%. In the final man-machine comparison, the accuracy of the GBM algorithm model for the classification of skin disease was significantly higher than that of young and inexperienced doctors. Conclusion: Dermatoscopy combined with machine learning can effectively improve the diagnosis and differential diagnosis accuracy of rosacea and other facial inflammatory skin diseases.

Discovery and Structure-Based Design of Macrocyclic Peptides Targeting STUB1.

Recent evidence suggests that deletion of STUB1─a pivotal negative regulator of interferon-γ sensing─may potentially clear malignant cells. However, current studies rely primarily on genetic approaches, as pharmacological inhibitors of STUB1 are lacking. Identifying a tool compound will be a step toward validating the target in a broader therapeutic sense. Herein, screening more than a billion macrocyclic peptides resulted in STUB1 binders, which were further optimized by a structure-enabled in silico design. The strategy to replace the macrocyclic peptides' hydrophilic and solvent-exposed region with a hydrophobic scaffold improved cellular permeability while maintaining the binding conformation. Further substitution of the permeability-limiting terminal aspartic acid with a tetrazole bioisostere retained the binding to a certain extent while improving permeability, suggesting a path forward. Although not optimal for cellular study, the current lead provides a valuable template for further development into selective tool compounds for STUB1 to enable target validation.

Oleic acid reduces steroidogenesis by changing the lipid type stored in lipid droplets of ovarian granulosa cells.

BACKGROUND: Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state, and it may have detrimental effects on female reproduction and fertility. Oleic acid induces lipid accumulation in bovine granulosa cells, which leads to a foam cell-like morphology and reduced steroidogenesis. However, why oleic acid increases lipid accumulation but decreases steroidogenesis remains unclear. This study focused on oleic acid's effects on lipid type and steroidogenesis. RESULTS: Oleic acid increased the lipid accumulation in a concentration-dependent manner and mainly increased the triglyceride level and decreased the cholesterol ester level. Oleic acid also led to a decline in estradiol and progesterone production in porcine granulosa cells in vitro. In addition, oleic acid up-regulated the expression of CD36 and diacylglycerol acyltransferase 2, but down-regulated the expression of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, scavenger receptor class B member 1 and acetyl-Coenzyme A acetyltransferase 2, as well as steroidogenesis-related genes, including cytochrome P450 family 11 subfamily A member 1, cytochrome P450 family 19 subfamily A member 1 and 3 as well as steroidogenic acute regulatory protein at the mRNA and protein levels. An oleic acid-rich diet also enhanced the triglyceride levels and reduced the cholesterol levels in ovarian tissues of female mice, which resulted in lower estradiol levels than in control-fed mice. Compared with the control, decreases in estrus days and the numbers of antral follicles and corpora lutea, as well as an increase in the numbers of the atretic follicles, were found in the oleic acid-fed female mice. CONCLUSIONS: Oleic acid changed the lipid type stored in lipid droplets of ovarian granulosa cells, and led to a decrease in steroidogenesis. These results improve our understanding of fertility decline in livestock that are in a negative energy-balance state.