Background
We have previously shown that endogenously active purinergic P2X7 receptors (P2X7Rs) in satellite glial cells of dorsal root ganglia (DRGs) stimulate ATP release. The ATP activates P2Y1Rs ...located in the enwrapped neuronal somata, resulting in down-regulation of P2X3Rs. This P2X7R-P2Y1-P2X3R inhibitory control significantly reduces P2X3R-mediated nociceptive responses. The underlying mechanism by which the activation of P2Y1Rs inhibits the expression of P2X3Rs remains unexplored.
Results
Examining the effect of the activation of p38 mitogen-activated protein kinase on the expression of P2X3Rs in DRGs, we found that the p38 activator, anisomycin (Anis), reduced the expression of P2X3Rs. Blocking the activity of SGCs by the glial Krebs cycle inhibitor, fluorocitrate, did not change the effect of Anis. These results suggest that neuronal p38 plays a major role in the inhibition of P2X3R expression. Western blotting analyses showed that inhibiting P2Y1Rs by MRS2179 (MRS) or blocking P2X7Rs by either oxATP or A740003 reduced pp38 and increased P2X3R expression in DRGs. These results are further supported by the immunohistochemical study showing that P2X7R and P2Y1R antagonists reduce the percentage of pp38-positive neurons. These observations suggest that activation of P2X7Rs and P2Y1Rs promotes p38 activity to exert inhibitory control on P2X3R expression. Since activation of p38 by Anis in the presence of either A740003 or MRS could overcome the block of P2X7R-P2Y1R inhibitory control, p38 in DRG neurons is downstream of P2Y1Rs. In addition, inhibition of p38 by SB202190 was found to prevent the P2X7R and P2Y1R block of P2X3R expression and increase P2X3R-mediated nociceptive flinch behaviors.
Conclusions
p38 in DRG neurons downstream of P2Y1R is necessary and sufficient for the P2X7R-P2Y1R inhibitory control of P2X3R expression.
Compensatory hepatocyte proliferation and other liver regenerative processes are activated to sustain normal physiological function after liver injury. A major mitogen for liver regeneration is ...hepatocyte growth factor (HGF), and a previous study indicated that progranulin could modulate c-met, the receptor for HGF, to initiate hepatic outgrowth from hepatoblasts during embryonic development. However, a role for progranulin in compensatory hepatocyte proliferation has not been shown previously. Therefore, this study was undertaken to clarify whether progranulin plays a regulatory role during liver regeneration. To this end, we established a partial hepatectomy regeneration model in adult zebrafish that express a liver-specific fluorescent reporter. Using this model, we found that loss of progranulin A (GrnA) function by intraperitoneal-injection of a Vivo-Morpholino impaired and delayed liver regeneration after partial hepatectomy. Furthermore, transcriptome analysis and confirmatory quantitative real-time PCR suggested that cell cycle progression and cell proliferation was not as active in the morphants as controls, which may have been the result of comparative downregulation of the HGF/c-met axis by 36 h after partial hepatectomy. Finally, liver-specific overexpression of GrnA in transgenic zebrafish caused more abundant cell proliferation after partial hepatectomy compared to wild types. Thus, we conclude that GrnA positively regulates HGF/c-met signaling to promote hepatocyte proliferation during liver regeneration.
Endometriosis is defined as the growth of endometrial glands and stromal cells in a heterotopic location with immune dysregulation. It usually leads to chronic pelvic pain and subfertility. Although ...various treatments are available, the recurrence rate remains high. Adipose tissue is an abundant source of multipotent mesenchymal adipose-derived stem cells (ADSCs). ADSCs display effects on not only tissue regeneration, but also immune regulation. Thus, the current study aims to test the effects of ADSCs on the growth of endometriosis.
ADSCs isolated from lipoaspiration-generated adipose tissue and their conditioned medium (ADSC-CM) were subjected to quality validation, including karyotyping as well as growth promotion and sterility tests for microbial contamination under Good Tissue Practice and Good Manufacturing Practice regulations. An autologous endometriosis mouse model was established by suturing endometrial tissue to peritoneal wall followed by treating with DMEM/F12 medium, ADSC-CM, ADSCs or ADSC-CM+ADSCs for 28 days. The area of endometriotic cysts and the degree of pelvic adhesion were measured. ICAM-1, VEGF and caspase 3 expression was assessed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Moreover, the mice were allowed to mate and deliver. The pregnancy outcomes were recorded. The ADSC-CM was subjected to proteomics analysis with further data mining with Ingenuity Pathway Analysis (IPA).
Both ADSC-CM and ADSCs passed quality validation. ADSC-CM reduced the area of endometriotic cysts. The inhibition by ADSC-CM was obliterated by adding ADSCs. The presence of ADSCs with or without ADSC-CM increased the peritoneal adhesion. ADSC-CM inhibited ICAM-1 and VEGF mRNA and protein expression, whereas the addition of ADSCs not only did not inhibit by itself, but also blocked the inhibition by ADSC-CM. The resorption rate was reduced by ADSC-CM. The number of live birth/dam and the survival rate of pup at 1 week-old were both increased by ADSC-CM in mice with endometriosis. IPA demonstrated that PTX3 was potentially critical for the inhibition of endometriosis by ADSC-CM due to its anti-inflammatory and antiangiogenic properties as well as its importance in implantation.
ADSC-CM inhibited endometriosis development and improved pregnancy outcomes in mice. Potential translation to clinical treatment for human endometriosis is expected.
Electroacupuncture has been shown to effectively reduce chronic pain in patients with nerve injury. The underlying mechanisms are not well understood. Accumulated evidence suggests that purinergic ...P2X3 receptors (P2X3Rs) in dorsal root ganglion neurons play a major role in mediating chronic pain associated with nerve injury. The aim of this study is to determine if electroacupuncture stimulation alters P2X3R activity in dorsal root ganglia to produce analgesia under neuropathic pain condition. Peripheral neuropathy was produced by ligation of the left lumbar 5 (L5) spinal nerve in rats. Low-frequency (2 Hz) electrical stimulation was applied to ipsilateral ST36 and BL60 acupoints in rats. The P2X3R agonist (α,β-meATP)-induced flinch responses were reduced after electroacupuncture treatment. Western analyses showed that P2X3R expression was upregulated in nerve-uninjured lumbar 4 (L4) dorsal root ganglion neurons ipsilateral to the spinal nerve ligation. Electroacupuncture-stimulation reversed the upregulation. In nerve-injured L5 dorsal root ganglia, P2X3R expression was substantially reduced. Electroacupuncture had no effect on the reduction. We also determined the injury state of P2X3R expressing dorsal root ganglion neurons using the neuronal injury marker, activating transcription factor 3 (ATF3). Immunohistochemical assay showed that in L4 dorsal root ganglia, almost all P2X3Rs were expressed in uninjured (ATF3−) neurons. Spinal nerve ligation increased the expression of P2X3Rs. Electroacupuncture reduced the increase in P2X3R expression without affecting the percentage of ATF + neurons. In ipsilateral L5 dorsal root ganglion neurons, spinal nerve ligation reduced the percentage of P2X3R + neurons and markedly increased the percentage of ATF3 + cells. Almost all of P2X3Rs were expressed in damaged (ATF3+) neurons. Electroacupuncture had no effect on spinal nerve ligation-induced changes in the percentage of P2X3R or percentage of ATF3 + cells in L5 dorsal root ganglia. These observations led us to conclude that electroacupuncture effectively reduces injury-induced chronic pain by selectively reducing the expression of P2X3Rs in nerve-uninjured L4 dorsal root ganglion neurons.
Conflicting data of the potential association between proton pump inhibitors (PPIs) and risk of dementia have been reported. This study aimed to examine the subsequent risk of incident dementia in ...older adults by categorizing subjects into different trajectories of longitudinal PPI use. A group‐based trajectory modeling was used to identify distinct groups with regard to longitudinal PPI use over 3 years and to further examine the association between the trajectories of PPI use and dementia in a 5‐year follow‐up. Among 10,533 older adults who initiated PPIs, three distinct trajectories of longitudinal PPI use were identified: short‐term (n = 7,406, 70.3%), intermittent (n = 1,528, 14.5%), and long‐term users (n = 1,599, 15.2%). Long‐term (hazard ratio (HR) = 0.99 (95% confidence interval (CI), 0.93–1.17)) and intermittent PPI users (HR = 0.91 (95% CI, 0.76–1.09)) were not associated with an increased risk of incident dementia compared with short‐term users. Regardless of pattern of use, PPIs did not appear to significantly increase the risk of dementia over a mean follow‐up period of 4 years.
Glucagon-like peptide-1 (GLP-1) receptor agonist use is associated with reduced mortality and improved cardiovascular outcomes in the general population with diabetes. Dipeptidyl peptidase-4 (DPP-4) ...inhibitors are commonly used antidiabetic agents for patients with advanced-stage chronic kidney disease (CKD). The association of these 2 drug classes with outcomes among patients with diabetes and advanced-stage CKD or end-stage kidney disease (ESKD) is not well understood.
To assess whether use of GLP-1 receptor agonists in a population with diabetes and advanced-stage CKD or ESKD is associated with better outcomes compared with use of DPP-4 inhibitors.
This retrospective cohort study used data on patients with type 2 diabetes and stage 5 CKD or ESKD obtained from the National Health Insurance Research Database of Taiwan. The study was conducted between January 1, 2012, and December 31, 2018. Data were analyzed from June 2020 to July 2021.
Treatment with GLP-1 receptor agonists compared with treatment with DPP-4 inhibitors.
All-cause mortality, sepsis- and infection-related mortality, and mortality related to major adverse cardiovascular and cerebrovascular events were compared between patients treated with GLP-1 receptor agonists and patients treated with DPP-4 inhibitors. Propensity score weighting was used to mitigate the imbalance among covariates between the groups.
Of 27 279 patients included in the study, 26 578 were in the DPP-4 inhibitor group (14 443 54.34% male; mean SD age, 65 13 years) and 701 in the GLP-1 receptor agonist group (346 49.36% male; mean SD age, 59 13 years). After weighting, the use of GLP-1 receptor agonists was associated with lower all-cause mortality (hazard ratio HR, 0.79; 95% CI, 0.63-0.98) and lower sepsis- and infection-related mortality (HR, 0.61; 95% CI, 0.40-0.91). Subgroup analysis demonstrated a lower risk of mortality associated with use of GLP-1 receptor agonists compared with DDP-4 inhibitors among patients with cerebrovascular disease (HR, 0.33; 95% CI, 0.12-0.86) than among those without cerebrovascular disease (HR, 0.89; 95% CI, 0.71-1.12) (P = .04 for interaction).
Treatment with GLP-1 receptor agonists was associated with lower all-cause mortality among patients with type 2 diabetes, advanced-stage CKD, and ESKD than was treatment with DPP-4 inhibitors. Additional well-designed, prospective studies are needed to confirm the potential benefit of GLP-1 receptor agonist treatment for patients with advanced CKD or ESKD.
The feedback strategy, or controlled exposure of pig herd to the porcine epidemic diarrhea virus (PEDV), significantly decreased losses during a severe outbreak in late 2013 in Taiwan. However, some ...pig farms still suffered from recurrent outbreaks. To evaluate the association between antibody titers and clinical manifestations, sera and colostra were analyzed from one pig farm that employed the feedback strategy. Furthermore, spike (S) gene full sequences from six positive samples of two farms with and without using feedback were compared to investigate the evolution of PEDV variants circulating in pig herds. The results in this study showed that high PEDV antibody titers do not correlate with the high rate of protection from PEDV infection. In addition, repeated feedback generated the emergence of PEDV variants with unique substitutions of N537S and Y561H in the COE domain and S769F in the SS6 epitopes. These mutations indicated the pathogenetic evolution of PEDV strains existing in the cycle of the feedback method. A very strict biosecurity practice to block the routes of pathogen transfer should be followed to achieve successful control of PEDV infections in pig herds.
Type 2 diabetes mellitus (T2DM) presents a challenge for individuals today, affecting their health and life quality. Besides its known complications, T2DM has been found to contribute to bone/mineral ...abnormalities, thereby increasing the vulnerability to bone fragility/fractures. However, there is still a need for appropriate diagnostic approaches and targeted medications to address T2DM-associated bone diseases. This study aims to investigate the relationship between changes in gut microbiota, T2DM, and osteoporosis. To explore this, a T2DM rat model was induced by combining a high-fat diet and low-dose streptozotocin treatment. Our findings reveal that T2DM rats have lower bone mass and reduced levels of bone turnover markers compared to control rats. We also observe significant alterations in gut microbiota in T2DM rats, characterized by a higher relative abundance of Firmicutes (F) and Proteobacteria (P), but a lower relative abundance of Bacteroidetes (B) at the phylum level. Further analysis indicates a correlation between the F/B ratio and bone turnover levels, as well as between the B/P ratio and HbA1c levels. Additionally, at the genus level, we observe an inverse correlation in the relative abundance of
. These findings show promise for the development of new strategies to diagnose and treat T2DM-associated bone diseases.
ATP-binding cassette transporters, including ABCB1 (P-glycoprotein) and ABCG2 (BCRP/MXR/ABCP), are pivotal in multidrug resistance (MDR) development in cancer patients undergoing conventional ...chemotherapy. The absence of approved therapeutic agents for multidrug-resistant cancers presents a significant challenge in effectively treating cancer. Researchers propose repurposing existing drugs to sensitize multidrug-resistant cancer cells, which overexpress ABCB1 or ABCG2, to conventional anticancer drugs. The goal of this study is to assess whether furmonertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor overcomes drug resistance mediated by ABCB1 and ABCG2 transporters. Furmonertinib stands out due to its ability to inhibit drug transport without affecting protein expression. The discovery of this characteristic was validated through ATPase assays, which revealed interactions between furmonertinib and ABCB1/ABCG2. Additionally, in silico docking of furmonertinib offered insights into potential interaction sites within the drug-binding pockets of ABCB1 and ABCG2, providing a better understanding of the underlying mechanisms responsible for the reversal of MDR by this repurposed drug. Given the encouraging results, we propose that furmonertinib should be explored as a potential candidate for combination therapy in patients with tumors that have high levels of ABCB1 and/or ABCG2. This combination therapy holds the potential to enhance the effectiveness of conventional anticancer drugs and presents a promising strategy for overcoming MDR in cancer treatment.
This study aimed to assess the outcome of a modified two-stage flexor tendon reconstruction using silicone tubes as antiadhesion devices while performing simultaneous tendon grafting.
From April 2008 ...to October 2019, 16 patients (21 fingers) with zone II flexor tendon injuries, who sustained failed tendon repair or neglected tendon laceration, were treated by a modified two-stage flexor tendon reconstruction. The first stage of treatment comprised flexor tendon reconstruction with interposition of silicone tubes to minimize fibrosis and adhesion around the tendon graft; the second stage of treatment comprised silicone tube removal under local anesthesia.
The patient median age was 38 (range, 22–65) years. After a median follow-up period of 14 (range, 12–84) months, the median total active motion (TAM) of fingers was 220° (range, 150–250°). Excellent and good TAM ratings were identified in 71.4%, 76.2%, and 76.2% according to the Strickland, modified Strickland, and American Society for Surgery of the Hand (ASSH) evaluation systems, respectively. At follow-up, complications included superficial infections in two fingers of one patient whose silicone tube was removed 4 weeks postoperatively. The most common complication was a flexion deformity of the proximal interphalangeal joint (four fingers) and/or distal interphalangeal joint (nine fingers). The rate of failed reconstruction was higher in patients with preoperative stiffness and infection.
Silicone tubes are suitable antiadhesion devices, and the modified two-stage flexor tendon reconstruction technique is an alternative procedure with a shorter rehabilitation period for complicated flexor tendon injury, compared with current popular reconstructions. Preoperative stiffness and postoperative infection may compromise the final clinical outcome.
Therapeutic IV.
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