Acta physiologica Sinica最新文献

Heart failure with preserved ejection fraction (HFpEF) is a type of heart failure characterized by left ventricular diastolic dysfunction with preserved ejection fraction. With the aging of the population and the increasing prevalence of metabolic diseases, such as hypertension, obesity and diabetes, the prevalence of HFpEF is increasing. Compared with heart failure with reduced ejection fraction (HFrEF), conventional anti-heart failure drugs failed to reduce the mortality in HFpEF due to the complex pathophysiological mechanism and multiple comorbidities of HFpEF. It is known that the main changes of cardiac structure of in HFpEF are cardiac hypertrophy, myocardial fibrosis and left ventricular hypertrophy, and HFpEF is commonly associated with obesity, diabetes, hypertension, renal dysfunction and other diseases, but how these comorbidities cause structural and functional damage to the heart is not completely clear. Recent studies have shown that immune inflammatory response plays a vital role in the progression of HFpEF. This review focuses on the latest research progress in the role of inflammation in the process of HFpEF and the potential application of anti-inflammatory therapy in HFpEF, hoping to provide new research ideas and theoretical basis for the clinical prevention and treatment in HFpEF.

This study aims to explore the auditory response characteristics of the thalamic reticular nucleus (TRN) in awake mice during auditory information processing, so as to deepen the understanding of TRN and explore its role in the auditory system. By in vivo electrophysiological single cell attached recording of TRN neurons in 18 SPF C57BL/6J mice, we observed the responses of 314 recorded neurons to two kinds of auditory stimuli, noise and tone, applied to mice. The results showed that TRN received projections from layer six of the primary auditory cortex (A1). Among 314 TRN neurons, 56.05% responded silently, 21.02% responded only to noise and 22.93% responded to both noise and tone. The neurons with noise response can be divided into three patterns according to their response time: onset, sustain and long-lasting, accounting for 73.19%, 14.49% and 12.32%, respectively. The response threshold of the sustain pattern neurons was lower than those of the other two types. Under noise stimulation, compared with A1 layer six, TRN neurons showed unstable auditory response (P < 0.001), higher spontaneous firing rate (P < 0.001), and longer response latency (P < 0.001). Under tone stimulation, TRN's response continuity was poor, and the frequency tuning was greatly different from that of A1 layer six (P < 0.001), but their sensitivity to tone was similar (P > 0.05), and TRN's tone response threshold was much higher than that of A1 layer six (P < 0.001). The above results demonstrate that TRN mainly undertakes the task of information transmission in the auditory system. The noise response of TRN is more extensive than the tone response. Generally, TRN prefers high-intensity acoustic stimulation.

Pain is a multi-dimensional emotional experience, and pain sensation and pain emotion are the two main components. As for pain, previous studies only focused on a certain link of the pain transmission pathway or a certain key brain region, and there is a lack of evidence that connectivity of brain regions is involved in pain or pain regulation in the overall state. The establishment of new experimental tools and techniques has brought light to the study of neural pathways of pain sensation and pain emotion. In this paper, the structure and functional basis of the neural pathways involved in the formation of pain sensation and the regulation of pain emotion in the nervous system above the spinal cord level, including thalamus, amygdala, midbrain periaqueductal gray (PAG), parabrachial nucleus (PB) and medial prefrontal cortex (mPFC), are reviewed in recent years, providing clues for the in-depth study of pain.

Lipid metabolism is a complex physiological process, which is closely related to nutrient regulation, hormone balance and endocrine function. It involves the interactions of multiple factors and signal transduction pathways. Lipid metabolism disorder is one of the main mechanisms to induce a variety of diseases, such as obesity, diabetes, non-alcoholic fatty liver disease, hepatitis, hepatocellular carcinoma and their complications. At present, more and more studies have found that the "dynamic modification" of N⁶-adenylate methylation (m⁶A) on RNA represents a new "post-transcriptional" regulation mode. m⁶A methylation modification can occur in mRNA, tRNA, ncRNA, etc. Its abnormal modification can regulate gene expression changes and alternative splicing events. Many latest references have reported that m⁶A RNA modification is involved in the epigenetic regulation of lipid metabolism disorder. Based on the major diseases induced by lipid metabolism disorders, we reviewed the regulatory roles of m⁶A modification in the occurrence and development of those diseases. These overall findings inform further in-depth investigations of the underlying molecular mechanisms regarding the pathogenesis of lipid metabolism disorders from the perspective of epigenetics, and provide reference for health prevention, molecular diagnosis and treatment of related diseases.

Early life nutritional environment is not only associated with the growth and development of children, but also affects the health of adults. Numerous epidemiological and animal studies suggest that early nutritional programming is an important physiological and pathological mechanism. DNA methylation is one of the important mechanisms of nutritional programming, which is catalyzed by DNA methyltransferase, a specific base of DNA covalently binds to a methyl group, to regulate gene expression. In this review, we summarize the role of DNA methylation in the "abnormal developmental planning" of key metabolic organs caused by excessive nutrition in early life, resulting in long-term obesity and metabolic disorders in the offspring, and explore the clinical significance of regulating DNA methylation levels through dietary interventions to prevent or reverse the occurrence of metabolic disorders in the early stage in a "deprogramming" manner.

Serum and glucocorticoid-regulated kinase 1 (SGK1) plays an important role in the physiological processes of hormone release, neuronal excitation and cell proliferation. SGK1 also participates in the pathophysiological processes of inflammation and apoptosis in the central nervous system (CNS). Increasing evidence demonstrates that SGK1 may serve as a target of the intervention of neurodegenerative diseases. In this article, we summarize the recent progress on the role and molecular mechanisms of SGK1 in the regulation of the function of the CNS. We also discuss the potential of newly discovered SGK1 inhibitors in the treatment of CNS diseases.

Pancreatic cancer has an insidious onset and lacks effective treatment methods, which is one of the tumors with the worst prognosis, so it is urgent to explore new treatment directions. Metabolic reprogramming is one of the important hallmarks of tumors. Pancreatic cancer cells in the harsh tumor microenvironment have comprehensively increased cholesterol metabolism in order to maintain strong metabolic needs, and cancer associated fibroblasts also provide cancer cells with a large amount of lipids. Cholesterol metabolism reprogramming involves the changes in the synthesis, uptake, esterification and metabolites of cholesterol, which are closely related to the proliferation, invasion, metastasis, drug resistance, and immunosuppression of pancreatic cancer. Inhibition of cholesterol metabolism has obvious anti-tumor effect. In this paper, the important effects and complexity of cholesterol metabolism in pancreatic cancer were comprehensively reviewed from perspectives of risk factors for pancreatic cancer, energy interaction between tumor-related cells, key targets of cholesterol metabolism and its targeted drugs. Cholesterol metabolism has a strict regulation and feedback mechanism, and the effect of single-target drugs in clinical application is not clear. Therefore, multi-target therapy of cholesterol metabolism is a new direction for pancreatic cancer treatment.

The purpose of this study was to investigate the effects of post-traumatic stress disorder (PTSD) on electrophysiological characteristics of glutamatergic and GABAergic neurons in dorsal hippocampus (dHPC) and ventral hippocampus (vHPC) in mice, and to elucidate the mechanisms underlying the plasticity of hippocampal neurons and memory regulation after PTSD. Male C57Thy1-YFP/GAD67-GFP mice were randomly divided into PTSD group and control group. Unavoidable foot shock (FS) was applied to establish PTSD model. The spatial learning ability was explored by water maze test, and the changes in electrophysiological characteristics of glutamatergic and GABAergic neurons in dHPC and vHPC were examined using whole-cell recording method. The results showed that FS significantly reduced the movement speed, and enhanced the number and percentage of freezing. PTSD significantly prolonged the escape latency in localization avoidance training, shortened the swimming time in the original quadrant, extended the swimming time in the contralateral quadrant, and increased absolute refractory period, energy barrier and inter-spike interval of glutamatergic neurons in dHPC and GABAergic neurons in vHPC, while decreased absolute refractory period, energy barrier and inter-spike interval of GABAergic neurons in dHPC and glutamatergic neurons in vHPC. These results suggest that PTSD can damage spatial perception of mice, down-regulate the excitability of dHPC and up-regulate the excitability of vHPC, and the underlying mechanism may involve the regulation of spatial memory by the plasticity of neurons in dHPC and vHPC.

To explore the changes of cold sensitivity after exposure to acute hypoxia and its mechanisms, Sprague-Dawley rats were divided into normoxia control group (21% O₂, 25 °C), 10% O₂ hypoxia group (10% O₂, 25 °C), 7% O₂ hypoxia group (7% O₂, 25 °C), normoxia cold group (21% O₂, 10 °C) and hypoxia cold group (7% O₂, 10 °C). Cold foot withdrawal latency and preference temperature of each group were measured, skin temperatures were estimated using an infrared thermographic imaging camera, body core temperature was recorded by wireless telemetry system, immunohistochemical staining was used to detect the expression of c-Fos in the lateral parabrachial nucleus (LPB). The results showed that acute hypoxia significantly prolonged the latency of cold foot withdrawal and significantly enhanced the intensity of cold stimulation for foot withdrawal, and the rats under hypoxia preferred cold temperature. Cold exposure (10 °C) for 1 h significantly enhanced the expression of c-Fos in LPB of rats in normoxia, while hypoxia inhibited cold-induced c-Fos expression. Acute hypoxia significantly increased the skin temperature of feet and tails, decreased the skin temperature of interscapular region, and decreased the body core temperature of rats. These results indicate that acute hypoxia can significantly blunt cold sensitivity through the inhibition of LPB, suggesting actively keeping warm measures should be taken at the early stage after ascent to high altitude to prevent the upper respiratory infection and acute mountain sickness.

This paper aimed to investigate the role and potential mechanism of p53 on primordial follicle activation. Firstly, the p53 mRNA expression in the ovary of neonatal mice at 3, 5, 7 and 9 days post-partum (dpp) and the subcellular localization of p53 were detected to confirm the expression pattern of p53. Secondly, 2 dpp and 3 dpp ovaries were cultured with p53 inhibitor Pifithrin-μ (PFT-μ, 5 μmol/L) or equal volume of dimethyl sulfoxide for 3 days. The function of p53 in primordial follicle activation was determined by hematoxylin staining and whole ovary follicle counting. The proliferation of cell was detected by immunohistochemistry. The relative mRNA levels and protein levels of the key molecules involved in the classical pathways associated with the growing follicles were examined by immunofluorescence staining, Western blot and real-time PCR, respectively. Finally, rapamycin (RAP) was used to intervene the mTOR signaling pathway, and ovaries were divided into four groups: Control, RAP (1 μmol/L), PFT-μ (5 μmol/L), PFT-μ (5 μmol/L) + RAP (1 μmol/L) groups. The number of follicles in each group was determined by hematoxylin staining and whole ovary follicle counting. The results showed that the expression of p53 mRNA was decreased with the activation of primordial follicles in physiological condition. p53 was expressed in granulosa cells and oocyte cytoplasm of the primordial follicles and growing follicles, and the expression of p53 in the primordial follicles was higher than that in the growing follicles. Inhibition of p53 promoted follicle activation and reduced the primordial follicle reserve. Inhibition of p53 promoted the proliferation of the granulosa cells and oocytes. The mRNA and protein expression levels of key molecules in the PI3K/AKT signaling pathway including AKT, PTEN, and FOXO3a were not significantly changed after PFT-μ treatment, while the expression of RPS6/p-RPS6, the downstream effectors of the mTOR signaling pathway, was upregulated. Inhibition of both p53 and mTOR blocked p53 inhibition-induced primordial follicle activation. Collectively, these findings suggest that p53 may inhibit primordial follicle activation through the mTOR signaling pathway to maintain the primordial follicle reserve.