Neurophysiological features of STN LFP underlying sleep fragmentation in Parkinson's disease.

BACKGROUND: Sleep fragmentation is a persistent problem throughout the course of Parkinson's disease (PD). However, the related neurophysiological patterns and the underlying mechanisms remained unclear. METHOD: We recorded subthalamic nucleus (STN) local field potentials (LFPs) using deep brain stimulation (DBS) with real-time wireless recording capacity from 13 patients with PD undergoing a one-night polysomnography recording, 1 month after DBS surgery before initial programming and when the patients were off-medication. The STN LFP features that characterised different sleep stages, correlated with arousal and sleep fragmentation index, and preceded stage transitions during N2 and REM sleep were analysed. RESULTS: Both beta and low gamma oscillations in non-rapid eye movement (NREM) sleep increased with the severity of sleep disturbance (arousal index (ArI)-betaNREM: r=0.9, p=0.0001, sleep fragmentation index (SFI)-betaNREM: r=0.6, p=0.0301; SFI-gammaNREM: r=0.6, p=0.0324). We next examined the low-to-high power ratio (LHPR), which was the power ratio of theta oscillations to beta and low gamma oscillations, and found it to be an indicator of sleep fragmentation (ArI-LHPRNREM: r=-0.8, p=0.0053; ArI-LHPRREM: r=-0.6, p=0.0373; SFI-LHPRNREM: r=-0.7, p=0.0204; SFI-LHPRREM: r=-0.6, p=0.0428). In addition, long beta bursts (>0.25 s) during NREM stage 2 were found preceding the completion of transition to stages with more cortical activities (towards Wake/N1/REM compared with towards N3 (p<0.01)) and negatively correlated with STN spindles, which were detected in STN LFPs with peak frequency distinguishable from long beta bursts (STN spindle: 11.5 Hz, STN long beta bursts: 23.8 Hz), in occupation during NREM sleep (ß=-0.24, p<0.001). CONCLUSION: Features of STN LFPs help explain neurophysiological mechanisms underlying sleep fragmentations in PD, which can inform new intervention for sleep dysfunction. TRIAL REGISTRATION NUMBER: NCT02937727.

Reciprocal negative feedback between Prrx1 and miR-140-3p regulates rapid chondrogenesis in the regenerating antler.

During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair.

Macrophage-Related Testicular Inflammation in Individuals with Idiopathic Non-Obstructive Azoospermia: A Single-Cell Analysis.

Male infertility is a global issue that seriously affects reproductive health. This study aimed to understand the underlying causes of idiopathic non-obstructive azoospermia (iNOA), which is a type of male infertility with unknown origins that accounts for 10-15% of cases. By using single-cell analysis techniques, we aimed to uncover the mechanisms of iNOA and gain insight into the cellular and molecular changes in the testicular environment. In this study, we performed bioinformatics analysis using scRNA-seq and microarray data obtained from the GEO database. The analysis included techniques such as pseudotime analysis, cell-cell communication, and hdWGCNA. Our study showed a significant difference between the iNOA and the normal groups, indicating a disorder in the spermatogenic microenvironment in iNOA. We observed a reduction in the proportion of Sertoli cells and blocked germ cell differentiation. Additionally, we found evidence of testicular inflammation related to macrophages and identified ODF2 and CABYR as potential biomarkers for iNOA.

Antler stem cells as a novel stem cell source for reducing liver fibrosis.

Liver fibrosis results from collagen fiber deposition. Antler stem cells (ASCs) naturally in vivo differentiate into cartilage, which is only made of Col II in collagen component; whereas liver fibrosis is caused by over-abundance of Col I and III. In addition, ASCs can effectively promote regenerative wound healing in which tissue contains very few collagen fibers (Col I). In this study, we investigate the therapeutic effects of ASCs in a rat model of CCl4-induced liver fibrosis. Rats were treated with ASCs for 4 weeks in vivo, then biochemical and histopathological analyses were performed. Furthermore, we established cell co-culture systems of hepatic stellate cells (HSCs) and ASCs and of M1 macrophages and ASCs in vitro. Mesenchymal stem cells (MSCs) were used as a positive control. The results showed that ASC transplantation alleviated liver fibrosis effectively as evidenced by reduced collagen accumulation, decreased fatty degeneration, increased hepatocyte regeneration, decreased inflammation and significantly enhanced liver function; moreover, ASCs decreased the expression of pro-fibrogenic factors including TGF-ß and α-SMA. Additionally, our study showed that ASCs inhibit HSC activation and proliferation by controlling the expression of MMPs, TIMP1, TGF-ß, α-SMA and COL1A2 involved in these processes. Our results suggested that ASCs alleviate liver fibrosis effectively and inhibit HSC activation. Thus, ASCs may serve as a novel stem cell source for the treatment of liver fibrosis in the clinic.

Visualizing context-dependent calcium signaling in encephalitogenic T cells in vivo by two-photon microscopy.

In experimental autoimmune encephalitis (EAE), autoimmune T cells are activated in the periphery before they home to the CNS. On their way, the T cells pass through a series of different cellular milieus where they receive signals that instruct them to invade their target tissues. These signals involve interaction with the surrounding stroma cells, in the presence or absence of autoantigens. To portray the serial signaling events, we studied a T-cell-mediated model of EAE combining in vivo two-photon microscopy with two different activation reporters, the FRET-based calcium biosensor Twitch1 and fluorescent NFAT. In vitro activated T cells first settle in secondary (2°) lymphatic tissues (e.g., the spleen) where, in the absence of autoantigen, they establish transient contacts with stroma cells as indicated by sporadic short-lived calcium spikes. The T cells then exit the spleen for the CNS where they first roll and crawl along the luminal surface of leptomeningeal vessels without showing calcium activity. Having crossed the blood-brain barrier, the T cells scan the leptomeningeal space for autoantigen-presenting cells (APCs). Sustained contacts result in long-lasting calcium activity and NFAT translocation, a measure of full T-cell activation. This process is sensitive to anti-MHC class II antibodies. Importantly, the capacity to activate T cells is not a general property of all leptomeningeal phagocytes, but varies between individual APCs. Our results identify distinct checkpoints of T-cell activation, controlling the capacity of myelin-specific T cells to invade and attack the CNS. These processes may be valuable therapeutic targets.

Anthocyanins Delay Ageing-Related Degenerative Changes in the Liver.

Liver ageing is a significant risk factor for chronic liver diseases. Anthocyanin is a food additive that has previously shown efficacy in increasing longevity. Here, we tested whether anthocyanins could protect young mice from accelerated ageing of the liver. Kunming mice were injected with D-galactose to accelerate ageing and were given 20 or 40 mg/kg anthocyanins as an intervention. After eight weeks, whole liver function and structure were evaluated, and the expression levels of genes involved in the DNA damage signalling pathway were assessed by Western blot analysis. Anthocyanins delayed the reduction of the liver index (p < 0.05), hepatic tissue injury and fibrosis. Anthocyanins also maintained the stability of the redox system (GSH-PX, T-SOD and MDA) in plasma and liver structures (p < 0.001) and reduced the levels of inflammatory factors (IL-1, IL-6 and TNF-α) in the liver (p < 0.05). Moreover, the expression levels of sensors (ATM and ATR), mediators (H2AX and γ-H2AX) and effectors (Chk1, Chk2, p53 and p-p53) in the DNA damage signalling pathway were all reduced. Anthocyanins could be widely used in the field of health products to slow ageing-related deterioration of liver function and structure by inhibiting DNA damage.

Antler thymosin ß10 reduces liver fibrosis via inhibiting TGF-ß1/SMAD pathway.

Hepatic stellate cell (HSC) activation is a crucial step in the development of liver fibrosis. Previous studies have shown that antler stem cells (AnSCs) inhibited HSC activation, suggesting that this may be achieved through secreting or releasing peptides. This study aimed to investigate whether AnSC-derived peptides (AnSC-P) could reduce liver fibrosis. The results showed that AnSC-P effectively reduced liver fibrosis in rats. Furthermore, we found that thymosin ß10 (Tß-10) was rich in AnSC-P, which may be the main component of AnSC-P contributing to the reduction in liver fibrosis. A further study showed that Tß-10 reduced liver fibrosis in rats, with a reduction in HYP and MDA levels in the liver tissues, a decrease in the serum levels of ALP, ALT, AST, and TBIL and an increase in TP and ALB. Moreover, Tß-10 decreased the expression levels of the genes related to the TGF-ß/SMAD signaling pathway in vivo. In addition, Tß-10 also inhibited TGF-ß1-induced HSC activation and decreased the expression levels of the TGF-ß/SMAD signaling pathway-related genes in HSCs in vitro. In conclusion, antler Tß-10 is a potential drug candidate for the treatment of liver fibrosis, the effect of which may be achieved via inhibition of the TGFß/SMAD signaling pathway.

SiRNF8 Delivered by DNA Framework Nucleic Acid Effectively Sensitizes Chemotherapy in Colon Cancer.

Background: The evident side effects and decreased drug sensitivity significantly restrict the use of chemotherapy. However, nanoparticles based on biomaterials are anticipated to address this challenge. Methods: Through bioinformatics analysis and colon cancer samples, we initially investigated the expression level of RNF8 in colon cancer. Next, we constructed nanocarrier for delivering siRNF8 based on DNA tetrahedron (si-Tet), and Doxorubicin (DOX) was further intercalated into the DNA structure (si-DOX-Tet) for combination therapy. Further, the effects and mechanism of RNF8 inhibition on the sensitivity of colon cancer cells to DOX chemotherapy have also been studied. Results: RNF8 expression was increased in colon cancer. Agarose gel electrophoresis, transmission electron microscopy, and size distribution and potential analysis confirmed the successful preparation of the two nanoparticles, with particle sizes of 10.29 and 37.29 nm, respectively. Fluorescence imaging reveals that the carriers can be internalized into colon cancer cells and escape from lysosomes after 12 hours of treatment, effectively delivering siRNF8 and DOX. Importantly, Western blot analysis verified treatment with 50nM si-Tet silenced RNF8 expression by approximately 50% in colon cancer cells, and combined treatment significantly inhibited cell proliferation. Furthermore, the CCK-8 assay demonstrated that si-Tet treatment enhanced the sensitivity of colon cancer cells to the three chemotherapeutic drugs. Significant more DNA damage was detected after treatment with both si-Tet or si-DOX-Tet. Further flow cytometry analysis revealed that si-DOX-Tet treatment led to significantly more apoptosis, approximately 1.6-fold higher than treatment with DOX alone. Mechanistically, inhibiting RNF8 led to decreased ABCG2 expression and DOX efflux, but increased DNA damage, thereby enhancing the chemotherapeutic effect of DOX. Conclusion: We have successfully constructed si-DOX-Tet. By inhibiting the expression of RNF8, it enhances the chemotherapy sensitivity of DOX. Therefore, this tetrahedral FNA nanocarrier offers a new approach for the combined treatment of colon cancer.

The intestinal epithelial-macrophage-crypt stem cell axis plays a crucial role in regulating and maintaining intestinal homeostasis.

The intestinal tract plays a vital role in both digestion and immunity, making its equilibrium crucial for overall health. This equilibrium relies on the dynamic interplay among intestinal epithelial cells, macrophages, and crypt stem cells. Intestinal epithelial cells play a pivotal role in protecting and regulating the gut. They form vital barriers, modulate immune responses, and engage in pathogen defense and cytokine secretion. Moreover, they supervise the regulation of intestinal stem cells. Macrophages, serving as immune cells, actively influence the immune response through the phagocytosis of pathogens and the release of cytokines. They also contribute to regulating intestinal stem cells. Stem cells, known for their self-renewal and differentiation abilities, play a vital role in repairing damaged intestinal epithelium and maintaining homeostasis. Although research has primarily concentrated on the connections between epithelial and stem cells, interactions with macrophages have been less explored. This review aims to fill this gap by exploring the roles of the intestinal epithelial-macrophage-crypt stem cell axis in maintaining intestinal balance. It seeks to unravel the intricate dynamics and regulatory mechanisms among these essential players. A comprehensive understanding of these cell types' functions and interactions promises insights into intestinal homeostasis regulation. Moreover, it holds potential for innovative approaches to manage conditions like radiation-induced intestinal injury, inflammatory bowel disease, and related diseases.

Conditioned Media from Deer Antler Stem Cells Effectively Alleviate Type 1 Diabetes Mellitus Possibly via Inhibiting the NF-κB Signaling Pathway.

BACKGROUND: Type 1 diabetes mellitus (T1D) represents a severe threat to human health. Persistent hyperglycemia and dyslipidemia can lead to damaged liver function, while effective interventions for these complications are currently lacking. Deer antler stem cells (AnSCs), a novel type of adult stem cells, significantly reduced liver injury, which was speculated to be achieved through the paracrine pathway. METHODS: In this study, AnSC-conditioned medium (AnSC-CM) was used to treat C57BL/6 mice with T1D symptoms induced by streptozotocin (STZ). The therapeutic effects of AnSC-CM on T1D were evaluated, and the underlying mechanism was investigated. RESULTS: It was shown that AnSC-CM alleviated the T1D symptom: decreased body weight, increased blood glucose levels and islet lesions, and reduced insulin secretion. Moreover, AnSC-CM treatment improved liver function and mitigated liver injury in T1D mice. Impressively, the therapeutic effects of AnSC-CM on T1D were better than those of bone marrow mesenchymal stem cell-CM (BMSC-CM). The mechanistic study revealed that AnSC-CM significantly downregulated the NF-κB signaling pathway in both pancreatic and liver tissues. CONCLUSIONS: Therapeutic effects of AnSC-CM on STZ-induced T1D and liver injury may be achieved through targeting the NF-κB signaling pathway.

Antler stem cell-derived exosomes promote regenerative wound healing via fibroblast-to-myofibroblast transition inhibition.

INTRODUCTION: The typical outcome of mammalian wound healing is scarring, a fibrotic process mediated by myofibroblast aggregation. Perfect healing in a clinical setting is relatively unexplored. Surprisingly, our previous studies have shown that the large wound (10 cm diameter or more) of the pedicle of deer naturally achieves regenerative restoration, realized through a paracrine pathway from adjacent antler stem cells (AnSCs). METHODS: AnSC-derived exosomes (AnSC-exos) were topically injected around the full-thickness wounds in a rat model. The effects on the rate of wound healing and the quality of healing were evaluated via morphological, histological, and molecular biological techniques on days 14 and 28 after surgery. RESULTS: The results showed that AnSC-exos significantly accelerated the rate of wound healing and improved healing quality, including regeneration of cutaneous appendages (hair follicles and sebaceous glands) and the distribution pattern of collagen (basket-weave-like) in the healed skin. These effects of AnSC-exos were comparable to those of AnSCs but were significantly more potent than those of exosomes derived from bone marrow mesenchymal stem cells (bMSC-exos). Furthermore, AnSC-exos treatment effectively inhibited fibroblast-to-myofibroblast transition (FMT), as evidenced by the reduction of full-thickness skin injury-induced FMT in vivo and TGF-ß1-induced FMT in vitro. CONCLUSION: AnSC-exos could effectively promote regenerative cutaneous wound healing, highly likely through FMT inhibition. This suggests that AnSC-exos treatment could provide the potential for a novel approach to induce regenerative wound healing in the clinical setting.

Antler stem cell exosomes alleviate pulmonary fibrosis via inhibiting recruitment of monocyte macrophage, rather than polarization of M2 macrophages in mice.

Pulmonary fibrosis (PF), a chronic interstitial lung disease, is characterized by over-abundant deposition of extracellular matrix consisting mainly of collagen I. In previous studies, we demonstrated that deer antler stem cells (AnSCs), a novel type of adult stem cell, are capable of significantly down-regulating collagen formation in different organs and tissues and speculated that they could effectively treat PF via reducing collagen deposition in the lung tissue. In the present study, we found that administration of AnSCs improved the survival rate of PF mice and reduced lung fibrosis, collagen deposition and myofibroblast differentiation. The effects of AnSC treatment were significantly better than the positive control (adipose-derived stem cells). Interestingly, AnSC-Exos were almost equally effective as AnSCs in treating PF, suggesting that the effects of AnSCs on reduction of PF may be mainly through a paracrine mechanism. Further, AnSC-Exos reduced the number of M2 macrophages, a type of macrophage that secrets pro-fibrotic factors to accelerate fibrotic progression, in the lung tissues. In vitro experiments showed that the effects of AnSC-Exos on macrophage modulation were likely achieved via inhibition of the recruitment of circulating monocyte-derived macrophages (reducing the number of macrophages), rather than via inhibition of M2 polarization of macrophages. Inhibition of macrophage recruitment by AnSCs may be achieved indirectly via inhibiting CCL7 expression in fibroblasts; both let-7b and let-7a were highly enriched in AnSC-Exos and may play a critical role in the inhibition of CCL7 expression of fibroblasts. Collectively, the use of antler stem cells or their exosomes opens up a novel strategy for PF treatment in the clinical setting.

Protein crotonylation: An emerging regulator in DNA damage response.

DNA damage caused by internal or external factors lead to increased genomic instability and various diseases. The DNA damage response (DDR) is a crucial mechanism that maintaining genomic stability through detecting and repairing DNA damage timely. Post-translational modifications (PTMs) play significant roles in regulation of DDR. Among the present PTMs, crotonylation has emerged as a novel identified modification that is involved in a wide range of biological processes including gene expression, spermatogenesis, cell cycle, and the development of diverse diseases. In the past decade, numerous crotonylation sites have been identified in histone and non-histone proteins, leading to a more comprehensive and deep understanding of the function and mechanisms in protein crotonylation. This review provides a comprehensive overview of the regulatory mechanisms of protein crotonylation and the effect of crotonylation in DDR. Furthermore, the effect of protein crotonylation in tumor development and progression is presented, to inspire and explore the novel strategies for tumor therapy.

Injectable hydrogel made from antler mesenchyme matrix for regenerative wound healing via creating a fetal-like niche.

BACKGROUND: Scar formation and loss of cutaneous appendages are the greatest challenges in cutaneous wound healing. Previous studies have indicated that antler reserve mesenchyme (RM) cells and their conditioned medium improved regenerative wound healing with partial recovery of cutaneous appendages. AIM: To develop hydrogels from the antler RM matrix (HARM) and evaluate the effect on wound healing. METHODS: We prepared the hydrogels from the HARM via enzymatic solubilization with pepsin. Then we investigated the therapeutic effects of HARM on a full-thickness cutaneous wound healing rat model using both local injections surrounding the wound and topical wound application. RESULTS: The results showed that HARM accelerated wound healing rate and reduced scar formation. Also, HARM stimulated the regeneration of cutaneous appendages and blood vessels, and reduced collagen fiber aggregation. Further study showed that these functions might be achieved via creating a fetal-like niche at the wound site. The levels of fetal wound healing-related genes, including Collagen III and TGFß3 treated with HARM were all increased, while the expression levels of Collagen I, TGFß1, and Engrailed 1 were decreased in the healing. Moreover, the number of stem cells was increased in the fetal-like niche created by HARM, which may contribute to the regeneration of cutaneous appendages. CONCLUSION: Overall, we successfully developed an injectable hydrogel made from antler RM matrix for the regenerative repair of full-thickness cutaneous wounds. We uncovered the molecular mechanism of the hydrogels in promoting regenerative wound healing, and thus pave the way for HARM to be developed for the clinic use.

Identification and targeting of cancer-associated fibroblast signature genes for prognosis and therapy in Cutaneous melanoma.

BACKGROUND: Cancer-associated fibroblasts (CAFs) play pivotal roles in tumor invasion and metastasis. However, studies on CAF biomarkers in Cutaneous Melanoma (CM) are still scarce. This study aimed to explore the potential CAF biomarkers in CM, propose the potential therapeutic targets, and provide new insights for targeted therapy of CAFs in CM. METHODS: We utilized weighted gene co-expression network analysis to identify CAF signature genes in CM, and conducted comprehensive bioinformatics analysis on the CAF risk score established by these genes. Moreover, single-cell sequencing analysis, spatial transcriptome analysis, and cell experiments were utilized for verifying the expression and distribution pattern of signature genes. Furthermore, molecular docking was employed to screen potential target drugs. RESULTS: FBLN1 and COL5A1, two crucial CAF signature genes, were screened to establish the CAF risk score. Subsequently, a comprehensive bioinformatic analysis of the CAF risk score revealed that high-risk score group was significantly enriched in pathways associated with tumor progression. Besides, CAF risk score was significantly negatively correlated with clinical prognosis, immunotherapy response, and tumor mutational burden in CM patients. In addition, FBLN1 and COL5A1 were further identified as CAF-specific biomarkers in CM by multi-omics analysis and experimental validation. Eventually, based on these two targets, Mifepristone and Dexamethasone were screened as potential anti-CAFs drugs. CONCLUSION: The findings indicated that FBLN1 and COL5A1 were the CAF signature genes in CM, which were associated with the progression, treatment, and prognosis of CM. The comprehensive exploration of CAF signature genes is expected to provide new insight for clinical CM therapy.

Transarterial chemoembolization combined donafenib with/without PD-1 for unresectable HCC in a multicenter retrospective study.

Background & aims: This multicenter retrospective study evaluated the efficacy and safety of transarterial chemoembolization (TACE) combined with donafenib and a programmed death-1 (PD-1) inhibitor (TACE+DP) and TACE combined with donafenib (TACE+D) for unresectable hepatocellular carcinoma (uHCC). Methods: The clinical data of 388 patients with uHCC who received TACE+DP or TACE+D as first-line treatment at six Chinese academic centers from July 2021 to July 2022 were collected and analyzed retrospectively. Patients in the TACE+DP group received an intravenous administration of a PD-1 inhibitor every three weeks and oral donafenib (0.2 g) twice daily until intolerable toxicity or disease progression. Patients in the TACE+D group received the same dose of donafenib for 3-5 days after TACE. Overall survival (OS) and progression-free survival (PFS)were analyzed by Kaplan-Meier method and log-rank test. The tumor response was compared between the two groups according to modified RECIST criteria. Adverse events were also analyzed between the two groups. Results: The TACE+D group included 157 patients and the TACE+DP group included 166 patients. Patients in the TACE+DP group had a longer median OS (18.1 vs. 13.2 months, P<0.001) and longer median PFS (10.6 vs. 7.9 months, P<0.001) than those in the TACE+D group. Patients in the TACE+DP group achieved a greater objective response rate (ORR; 50.6% vs. 41.4%, P=0.019) and greater disease control rate (DCR) (89.2% vs. 82.8%, P=0.010) than those in the TACE+D group. No significant differences were found in the incidence or severity of adverse events between the TACE+DP and TACE+D groups (any grade: 92.9% vs. 94.6%, P=0.270; grade 3 or 4: 33.8% vs. 37.3%, P=0.253). Conclusion: With favorable safety and tolerability, TACE combined with donafenib and PD-1 inhibitors significantly improved PFS, OS, and ORR compared to TACE combined with donafenib.

A population of stem cells with strong regenerative potential discovered in deer antlers.

The annual regrowth of deer antlers provides a valuable model for studying organ regeneration in mammals. We describe a single-cell atlas of antler regrowth. The earliest-stage antler initiators were mesenchymal cells that express the paired related homeobox 1 gene (PRRX1+ mesenchymal cells). We also identified a population of "antler blastema progenitor cells" (ABPCs) that developed from the PRRX1+ mesenchymal cells and directed the antler regeneration process. Cross-species comparisons identified ABPCs in several mammalian blastema. In vivo and in vitro ABPCs displayed strong self-renewal ability and could generate osteochondral lineage cells. Last, we observed a spatially well-structured pattern of cellular and gene expression in antler growth center during the peak growth stage, revealing the cellular mechanisms involved in rapid antler elongation.

Tracing the geographic origin of velvet antlers in China via stable isotope analyses.

Multielement (H, C, N, O) stable isotope ratio analysis was used to discriminate the geographical origin of velvet antlers (VAs) of deer from ten provinces in China. Ratios of 2H/1H, 13C/12C, 15N/14N, and 18O/16O in the VA samples were measured using isotope ratio mass spectrometry. The results showed that there were highly significant differences in the mean isotopic values and in four isotopic ratios between VA samples from the ten provinces. The most significant difference among the four isotope ratios was in δ 2H ratio of VA samples; regions with a more humid climate and higher average ambient temperatures had higher δ 2H ratios than those with dry climates and lower temperatures. These results demonstrate that the multiple stable isotopic ratio approach is a powerful tool to help trace the geographical origin of VAs, and could be adopted by government officials to help protect consumer interests from improper labeling in VA markets.

M6A regulator-mediated immune infiltration and methylation modification in hepatocellular carcinoma microenvironment and immunotherapy.

Introduction: Tremendous evidence indicates that N6-methyladenosine (m6A) epigenetic modification and m6A-related enzymes constitute a complex network, which jointly regulates prevailing pathological processes and various signaling pathways in humankind. Currently, the role of the m6A-mediated molecular regulatory network in hepatocellular carcinoma (HCC) remains elusive. Methods: We recruited expression and pathological files of 368 HCC patients from The Cancer Genome Atlas cohort. Four public datasets serve as external authentication sets for nearest template prediction (NTP) validation. The correlation between 35 regulators and their prognostic value was compared. Gene set variation analysis (GSVA) was used to explore the latent mechanism. Four independent algorithms (ssGSEA, xCell, MCP-counter, and TIMER) were used to calculate the ratio of tumor cells and non-tumor cells to evaluate the tumor immune microenvironment. The m6Ascore model was established by principal component analysis (PCA). Prediction of immunotherapy and potential drugs was performed using TIDE and SubMap. Results: A total of 35 m6A regulators were widely associated, most of which were risk factors for HCC patients. The m6A phenotypic-cluster revealed differences in regulator transcriptional level, gene mutation frequency, functional pathways, and immune cell infiltration abundance under distinct m6A patterns. As expected, the m6A gene cluster confirmed the aforementioned results. The m6Ascore model further found that patients in the high-m6Ascore group were associated with lower tumor purity, higher enrichment of immune and stromal cells, upregulation of metabolic pathways, lower expression of m6A regulators, and favorable outcomes. Low-m6Ascore patients were associated with adverse outcomes. Notably, low-m6Ascore patients might be more sensitive to anti-PD-L1 therapy. Conclusion: This study found that a classification model based on the m6A manner could predict HCC prognosis and response to immunotherapy for HCC patients, which might improve prognosis and contribute to clinical individualized decision-making.

Placental stem cells-derived exosomes stimulate cutaneous wound regeneration via engrailed-1 inhibition.

Introduction: Skin wounds generally heal by scarring, a fibrotic process mediated by the Engrailed-1 (EN1) fibroblast lineage. Scar is detrimental to tissue structure and function, but perfect healing in clinical settings remains to be explored. Recent studies have shown that mesenchymal stem cell (MSC) transplantation can reduce scarring Methods: Here, we investigated the effects of placental MSCs (pMSCs) and exosomes derived from pMSCs (pMSC-exos) on wound healing using a full-thickness rat model. Results: The results showed that placental MSCs significantly accelerated the wound healing rate. Moreover, placental MSCs improved the quality of wound healing, including regenerating cutaneous appendages (hair follicles and sebaceous glands), decreasing collagen I and increasing collagen III, and improving collagen pattern (basket-wave-like) in the healed skin. placental MSCs treatment also increased the regeneration of blood vessels. Importantly, all these listed effects of placental MSCs were comparable to those of exosomes derived from pMSCs, but significantly stronger than those of adipose MSC-derived exosomes (aMSC-exos). Further studies showed that the effects of placental MSCs and exosomes derived from pMSCs on wound regeneration may be mainly achieved via the down-regulation of the Yes-associated protein signaling pathway, thus inhibiting the activation of EN1. Discussion: In summary, placental MSCs could effectively stimulate wound regeneration, and their effect could be achieved through their exosomes. This suggests that exosomes derived from pMSCs treatment could be used as a novel cell-free approach to induce wound regeneration in clinical settings.