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Cell Reports May 2024Glucose has long been considered a primary energy source for synaptic function. However, it remains unclear to what extent alternative fuels, such as lactate/pyruvate,...
Glucose has long been considered a primary energy source for synaptic function. However, it remains unclear to what extent alternative fuels, such as lactate/pyruvate, contribute to powering synaptic transmission. By detecting individual release events in hippocampal synapses, we find that mitochondrial ATP production regulates basal vesicle release probability and release location within the active zone (AZ), evoked by single action potentials. Mitochondrial inhibition shifts vesicle release closer to the AZ center and alters the efficiency of vesicle retrieval by increasing the occurrence of ultrafast endocytosis. Furthermore, we uncover that terminals can use oxidative fuels to maintain the vesicle cycle during trains of activity. Mitochondria are sparsely distributed along hippocampal axons, and we find that terminals containing mitochondria display enhanced vesicle release and reuptake during high-frequency trains. Our findings suggest that mitochondria not only regulate several fundamental features of synaptic transmission but may also contribute to modulation of short-term synaptic plasticity.
PubMed: 38758651
DOI: 10.1016/j.celrep.2024.114218 -
Frontiers in Microbiology 2024Cryopreservation of semen can give full play to the reproductive advantages of male animals. However, in actual production, due to the poor frost resistance of sheep...
INTRODUCTION
Cryopreservation of semen can give full play to the reproductive advantages of male animals. However, in actual production, due to the poor frost resistance of sheep semen and the low conception rate, the promotion of sheep frozen semen is greatly hindered. Therefore, it is urgent to improve the frost resistance of semen to improve the quality of frozen semen. At present, most studies on improving the quality of frozen semen are based on the improvement of semen dilutions, and few studies on improving the freezing resistance of ram semen by feeding functional amino acids.
METHODS
Therefore, 24 Turpan black rams were divided into high antifreeze group (HF) and a low antifreeze group (LF) Each of these groups was further randomly divided into control and experimental subgroups. The control subgroup was fed a basal diet, while the experimental subgroup received an additional 12 g/d of -Cit supplementation based on the control group for a duration of 90 days.
RESULTS
The results showed that Following -Cit supplementation, the experimental group demonstrated significantly elevated sperm density and VSL (Velocity of straight line), T-AOC, GSH-Px, and NO levels in fresh semen compared to the control group ( < 0.01). After thawing, the experimental group exhibited significantly higher levels of T-AOC, GSH-Px, and NO compared to the control group ( < 0.01). Additionally, the HFT group, after thawing frozen semen, displayed significantly higher HK1 protein expression compared to the control group. The number of spermatogonia, spermatocytes, and sperm cells in the HFT group was significantly higher than that in the HFC group. Moreover, 16S rRNA sequence analysis showed that , and were significantly enriched in the rumen of the HFT group, while was significantly enriched in the HFC group. In the duodenum, , and were significantly enriched in the HFT group, whereas and were significantly enriched in the HFC group.
DISCUSSION
Under the conditions employed in this study, -Cit supplementation was found to enhance the intestinal flora composition in rams, thereby improving semen quality, enhancing the antifreeze performance of semen, and promoting the development of testicular spermatogenic cells.
PubMed: 38756735
DOI: 10.3389/fmicb.2024.1396796 -
Frontiers in Neurology 2024The optimal placement of a cochlear implant (CI) electrode inside the scala tympani compartment to create an effective electrode-neural interface is the base for a... (Review)
Review
The optimal placement of a cochlear implant (CI) electrode inside the scala tympani compartment to create an effective electrode-neural interface is the base for a successful CI treatment. The characteristics of an effective electrode design include (a) electrode matching every possible variation in the inner ear size, shape, and anatomy, (b) electrically covering most of the neuronal elements, and (c) preserving intra-cochlear structures, even in non-hearing preservation surgeries. Flexible electrode arrays of various lengths are required to reach an angular insertion depth of 680° to which neuronal cell bodies are angularly distributed and to minimize the rate of electrode scalar deviation. At the time of writing this article, the current scientific evidence indicates that straight lateral wall electrode outperforms perimodiolar electrode by preventing electrode tip fold-over and scalar deviation. Most of the available literature on electrode insertion depth and hearing outcomes supports the practice of physically placing an electrode to cover both the basal and middle turns of the cochlea. This is only achievable with longer straight lateral wall electrodes as single-sized and pre-shaped perimodiolar electrodes have limitations in reaching beyond the basal turn of the cochlea and in offering consistent modiolar hugging placement in every cochlea. For malformed inner ear anatomies that lack a central modiolar trunk, the perimodiolar electrode is not an effective electrode choice. Most of the literature has failed to demonstrate superiority in hearing outcomes when comparing perimodiolar electrodes with straight lateral wall electrodes from single CI manufacturers. In summary, flexible and straight lateral wall electrode type is reported to be gentle to intra-cochlear structures and has the potential to electrically stimulate most of the neuronal elements, which are necessary in bringing full benefit of the CI device to recipients.
PubMed: 38756216
DOI: 10.3389/fneur.2024.1348439 -
Journal of Animal Science and... May 2024Comprehending the patterns of alteration in boar semen quality and identifying effective nutritional interventions are crucial for enhancing the productivity of...
BACKGROUND
Comprehending the patterns of alteration in boar semen quality and identifying effective nutritional interventions are crucial for enhancing the productivity of commercial pig systems. This study aimed to examine the alteration in semen quality in boars, and assess the impact of protocatechuic acid (PCA) on semen quality during the phase of declining semen quality.
METHODS
In Exp. 1, a total of 38 Pig Improvement Company (PIC) boars were selected and their semen quality data were recorded from the age of 9 to 37 months. In Exp. 2, 18 PIC boars (28 months old) were randomly assigned into three groups (n = 6) and fed a basal diet, a basal diet containing 500 or 1,000 mg/kg PCA, respectively. The experiment lasted for 12 weeks.
RESULTS
The semen volume, concentration, and total number of spermatozoa in boars exhibited an increase from 9 to 19 months old and showed a significant linear decreased trend in 28, 24, and 22 months old. Sperm motility displayed an upward trajectory, reaching its peak at 20 months of age, and showed a significant linear decreased trend at 20 months old. Dietary supplementation of PCA demonstrated an effect to mitigate the decrease in semen volume, concentration of spermatozoa, total number of spermatozoa (P > 0.05), and significantly increased the sperm motility (P < 0.05). Moreover, supplementation of 1,000 mg/kg PCA significantly increased the sperm viability (P < 0.05). Analysis on cellular signaling pathways revealed that PCA restored serum testosterone levels and alleviated oxidative damage by upregulating the expression of HO-1, SOD2, and NQO1 in testicular stromal cells. Notably, PCA can enhance phosphorylation by selectively binding to AMP-activated protein kinase (AMPK) protein, thereby improving sperm mitochondrial function and augmenting sperm motility via PGC-1/Nrf1.
CONCLUSIONS
These data elucidated the pattern of semen quality variation in boars within the age range of 9 to 37 months old, and PCA has the potential to be a natural antioxidant to enhance sperm quality through modulation of the AMPK/PGC-1/Nrf1 signaling pathway.
PubMed: 38755656
DOI: 10.1186/s40104-024-01031-6 -
Communications Biology May 2024The hepatic acute-phase response is characterized by a massive upregulation of serum proteins, such as haptoglobin and serum amyloid A, at the expense of liver...
The hepatic acute-phase response is characterized by a massive upregulation of serum proteins, such as haptoglobin and serum amyloid A, at the expense of liver homeostatic functions. Although the transcription factor hepatocyte nuclear factor 4 alpha (HNF4A) has a well-established role in safeguarding liver function and its cistrome spans around 50% of liver-specific genes, its role in the acute-phase response has received little attention so far. We demonstrate that HNF4A binds to and represses acute-phase genes under basal conditions. The reprogramming of hepatic transcription during inflammation necessitates loss of HNF4A function to allow expression of acute-phase genes while liver homeostatic genes are repressed. In a pre-clinical liver organoid model overexpression of HNF4A maintained liver functionality in spite of inflammation-induced cell damage. Conversely, HNF4A overexpression potently impaired the acute-phase response by retaining chromatin at regulatory regions of acute-phase genes inaccessible to transcription. Taken together, our data extend the understanding of dual HNF4A action as transcriptional activator and repressor, establishing HNF4A as gatekeeper for the hepatic acute-phase response.
Topics: Hepatocyte Nuclear Factor 4; Acute-Phase Reaction; Animals; Liver; Transcriptome; Mice; Down-Regulation; Humans; Mice, Inbred C57BL; Male; Gene Expression Regulation
PubMed: 38755249
DOI: 10.1038/s42003-024-06288-1 -
Endocrinology and Metabolism (Seoul,... May 2024This study investigates the impact of fluctuating lipid levels on endothelial dysfunction.
BACKGROUND
This study investigates the impact of fluctuating lipid levels on endothelial dysfunction.
METHODS
Human aortic and umbilical vein endothelial cells were cultured under varying palmitic acid (PA) concentrations: 0, 50, and 100 μM, and in a variability group alternating between 0 and 100 μM PA every 8 hours for 48 hours. In the lipid variability group, cells were exposed to 100 μM PA during the final 8 hours before analysis. We assessed inflammation using real-time polymerase chain reaction, Western blot, and cytokine enzyme-linked immunosorbent assay (ELISA); reactive oxygen species (ROS) levels with dichlorofluorescin diacetate assay; mitochondrial function through oxygen consumption rates via XF24 flux analyzer; and endothelial cell functionality via wound healing and cell adhesion assays. Cell viability was evaluated using the MTT assay.
RESULTS
Variable PA levels significantly upregulated inflammatory genes and adhesion molecules (Il6, Mcp1, Icam, Vcam, E-selectin, iNos) at both transcriptomic and protein levels in human endothelial cells. Oscillating lipid levels reduced basal respiration, adenosine triphosphate synthesis, and maximal respiration, indicating mitochondrial dysfunction. This lipid variability also elevated ROS levels, contributing to a chronic inflammatory state. Functionally, these changes impaired cell migration and increased monocyte adhesion, and induced endothelial apoptosis, evidenced by reduced cell viability, increased BAX, and decreased BCL2 expression.
CONCLUSION
Lipid variability induce endothelial dysfunction by elevating inflammation and oxidative stress, providing mechanistic insights into how lipid variability increases cardiovascular risk.
PubMed: 38752267
DOI: 10.3803/EnM.2023.1915 -
Frontiers in Cellular and Infection... 2024Non-typeable (NTHi) and (Mcat) are two common respiratory tract pathogens often associated with acute exacerbations in Chronic Obstructive Pulmonary Disease (COPD) as...
Non-typeable (NTHi) and (Mcat) are two common respiratory tract pathogens often associated with acute exacerbations in Chronic Obstructive Pulmonary Disease (COPD) as well as with otitis media (OM) in children. Although there is evidence that these pathogens can adopt persistence mechanisms such as biofilm formation, the precise means through which they contribute to disease severity and chronicity remains incompletely understood, posing challenges for their effective eradication. The identification of potential vaccine candidates frequently entails the characterization of the host-pathogen interplay even though this approach is limited by the fact that conventional models do not permit long term bacterial infections. In the present work, by using air-liquid-interface (ALI) human airway models, we aimed to recreate COPD-related persistent bacterial infections. In particular, we explored an alternative use of the ALI system consisting in the assembly of an inverted epithelium grown on the basal part of a transwell membrane with the aim to enable the functionality of natural defense mechanisms such as mucociliary clearance and cellular extrusion that are usually hampered during conventional ALI infection experiments. The inversion of the epithelium did not affect tissue differentiation and considerably delayed NTHi or Mcat infection progression, allowing one to monitor host-pathogen interactions for up to three weeks. Notably, the use of these models, coupled with confocal and transmission electron microscopy, revealed unique features associated with NTHi and Mcat infection, highlighting persistence strategies including the formation of intracellular bacterial communities (IBCs) and surface-associated biofilm-like structures. Overall, this study demonstrates the possibility to perform long term host-pathogen investigations with the aim to define persistence mechanisms adopted by respiratory pathogens and individuate potential new vaccine targets.
Topics: Moraxella catarrhalis; Humans; Haemophilus influenzae; Biofilms; Moraxellaceae Infections; Persistent Infection; Host-Pathogen Interactions; Haemophilus Infections; Pulmonary Disease, Chronic Obstructive; Models, Biological; Respiratory Tract Infections; Epithelial Cells
PubMed: 38751999
DOI: 10.3389/fcimb.2024.1397940 -
Acta Dermato-venereologica May 2024Photodynamic therapy is an approved treatment for primary, superficial, and small nodular basal cell carcinomas with a thickness of < 2 mm located on low-risk sites.... (Comparative Study)
Comparative Study
Photodynamic therapy is an approved treatment for primary, superficial, and small nodular basal cell carcinomas with a thickness of < 2 mm located on low-risk sites. Histologically verified basal cell carcinomas clinically assessed as suited for photodynamic therapy were included. The study aimed to investigate the agreement between clinical and histological assessments of basal cell carcinoma subtypes and thickness of tumours selected for photodynamic therapy with histopathological evaluation as a reference. A total of 343 tumours were included. The agreement between clinical and histological diagnosis of basal cell carcinoma subtype was 72% (p < 0.001). Clinical assessment of subtype had a sensitivity of 93% and specificity of 55% for superficial tumours and a sensitivity of 55% and specificity of 85% for nodular tumours. The mean ± SD thickness values by clinical and histological assessments were 0.95 ± 0.53 and 0.86 ± 0.75. The difference of 0.09 mm was statistically significant (p = 0.017), but not considered to be clinically relevant, although the differences between specific subgroups could be relevant. Among basal cell carcinomas clinically diagnosed as superficial, 91% were histologically consistent with the current photodynamic therapy criteria. The main results suggest that histopathological evaluation should precede photodynamic therapy to ensure selection of suitable basal cell carcinomas. In selected cases, the clinical diagnosis alone may be adequate before proceeding with photodynamic therapy.
Topics: Humans; Carcinoma, Basal Cell; Photochemotherapy; Skin Neoplasms; Male; Female; Aged; Middle Aged; Aged, 80 and over; Predictive Value of Tests; Biopsy; Adult; Patient Selection; Photosensitizing Agents; Retrospective Studies
PubMed: 38751175
DOI: 10.2340/actadv.v104.18308 -
European Journal of Medical Research May 2024Odontogenic keratocysts exhibit frequent recurrence, distinctive histopathological traits, a tendency towards aggressive clinical behavior, and a potential linkage to... (Review)
Review
OBJECTIVES
Odontogenic keratocysts exhibit frequent recurrence, distinctive histopathological traits, a tendency towards aggressive clinical behavior, and a potential linkage to the nevoid basal cell carcinoma syndrome. The aim of this systematic review is to compile insights concerning the control of this condition and assess the effectiveness of various treatment approaches in reducing the likelihood of recurrence.
MATERIALS AND METHODS
The following systematic review adhered to the PRISMA guidelines. The systematic revision was registered on PROSPERO and structured around the questions related to the population, intervention, control, outcome and study design (PICOS).
RESULTS
After conducting a search on the PubMed database, we initially identified 944 records. After using end-note software to remove duplicate entries, results totally with 462 distinct records. A thorough review of the titles and abstracts of these articles led to the selection of 50 papers for in-depth examination. Ultimately, following the application of our eligibility criteria, we incorporated 11 articles into our primary outcome analysis.
CONCLUSION
Among the studies examined, the most common location for these lesions was found to be in the area of the mandibular ramus and the posterior region of the mandible. In cases where the exact location wasn't specified, the mandible emerged as the predominant site. When we considered the characteristics of these lesions in studies that mentioned locularity, most were described as unilocular in two studies, while in two other studies, the prevalence of multilocular lesions was observed. Risk factors associated with keratocyst recurrence include younger patient age, the presence of multilocular lesions, larger lesion size, and a longer anteroposterior dimension. Certain treatment methods have demonstrated a lack of relapses. These include the use of 5-fluorouracil, marsupialization, enucleation with peripheral ostectomy or resection, enucleation and curettage, as well as resection without creating continuity defects. However, it is important to note that further research is essential. Prospective studies and randomized trials are needed to collect more comprehensive evidence regarding the effectiveness of various treatment approaches and follow-up protocols for managing odontogenic keratocysts.
CLINICAL RELEVANCE
Odontogenic keratocysts still enter into differential diagnoses with other lesions that affect the jaw bones such as ameloblastama and other tumor forms, furthermore it is not free from recurrence, therefore the therapeutic approach to the lesion aimed at its elimination can influence both the possible recurrence and complications, knowledge of the surgical methods that offer the most predictable and clinically relevant result for the management of follow-up and recurrences.
Topics: Humans; Odontogenic Cysts
PubMed: 38750607
DOI: 10.1186/s40001-024-01854-z -
Nature Communications May 2024Basal progenitor cells are crucial for maintaining foregut (the esophagus and forestomach) homeostasis. When their function is dysregulated, it can promote inflammation...
Basal progenitor cells are crucial for maintaining foregut (the esophagus and forestomach) homeostasis. When their function is dysregulated, it can promote inflammation and tumorigenesis. However, the mechanisms underlying these processes remain largely unclear. Here, we employ genetic mouse models to reveal that Jag1/2 regulate esophageal homeostasis and foregut tumorigenesis by modulating the function of basal progenitor cells. Deletion of Jag1/2 in mice disrupts esophageal and forestomach epithelial homeostasis. Mechanistically, Jag1/2 deficiency impairs activation of Notch signaling, leading to reduced squamous epithelial differentiation and expansion of basal progenitor cells. Moreover, Jag1/2 deficiency exacerbates the deoxycholic acid (DCA)-induced squamous epithelial injury and accelerates the initiation of squamous cell carcinoma (SCC) in the forestomach. Importantly, expression levels of JAG1/2 are lower in the early stages of human esophageal squamous cell carcinoma (ESCC) carcinogenesis. Collectively, our study demonstrates that Jag1/2 are important for maintaining esophageal and forestomach homeostasis and the onset of foregut SCC.
Topics: Animals; Jagged-1 Protein; Homeostasis; Esophageal Neoplasms; Esophagus; Stem Cells; Mice; Jagged-2 Protein; Humans; Carcinogenesis; Esophageal Squamous Cell Carcinoma; Mice, Knockout; Signal Transduction; Carcinoma, Squamous Cell; Receptors, Notch; Cell Differentiation; Male; Female
PubMed: 38750026
DOI: 10.1038/s41467-024-48347-5