生理学报最新文献

Neural synchronization activity is considered a key aspect of information processing in the nervous system. Local synchronization within different frequency ranges and inter-regional synchronization are ubiquitous and related to various behavioral and cognitive functions. As memory is a higher cognitive function of the brain, the formation and consolidation of memory are closely related to neural synchronization activity. This article provides an overview of the research progress on the relationship between neural synchronization activity and memory consolidation, focusing primarily on the neuro-oscillatory activities across multiple brain regions during non-rapid eye movement (NREM) sleep in vivo, as well as the synchronous burst activity in cultured neural networks in vitro. Finally, we analyzed the existing issues in current research and provided a perspective on future relevant studies.

Intracerebral hemorrhage (ICH) is the most common subtype of stroke with high disability and high mortality rates. Due to the hypertension with arteriosclerosis, hemopathy and cerebrovascular amyloidosis, the influx of blood from ruptured vessels into the brain destroys the cerebral parenchyma and results in dysfunction of central nervous system because of hematoma compression and a series of toxic metabolites. The cerebral parenchyma consists of gray and white matter. The white matter consists of myelinated axons and oligodendrocytes, whereas the gray matter consists of neuronal cell bodies and dendrites. Currently, most of studies have explored the mechanisms of gray matter injury. But researches of white matter injury (WMI) are still in their infancy, which may be partially responsible for the failure of treatments with neuroprotectants targeting degenerating neuronal cells. In recent years, researchers have progressively identified pathophysiological mechanisms of WMI after ICH including mass effect, neuroinflammation and oxidative stress, but information on the molecular mechanisms of WMI and its effective treatment remains limited. In this paper, we will describe the structure and function of white matter, summarize pathology of WMI and focus on the research advances in the molecular mechanisms and therapeutic strategies of WMI after ICH.

The present study aimed to investigate the effect of human umbilical cord mesenchymal stem cells (MSCs)-derived exosomes (MSCs-Exo) on mice with hypoxic pulmonary hypertension (HPH). MSCs were isolated and cultured from human umbilical cords under aseptic conditions, and exosomes were extracted from the supernatants and identified. Healthy SPF C57BL/6 mice were randomly divided into three groups: normoxic group, hypoxic group, and hypoxic+MSCs-Exo group. Mice in the hypoxic group and the hypoxic+MSCs-Exo group were maintained for 28 d at an equivalent altitude of 5 000 m in a hypobaric chamber to establish HPH mouse model. The mice in the hypoxic+MSCs-Exo group were injected with MSCs-Exo via tail vein before hypoxia and on days 1, 3, 5 and 9 of hypoxia, and the mice in the other two groups were injected with PBS. At the end of the experiment, echocardiography was performed to detect pulmonary arterial acceleration time/pulmonary arterial ejection time ratio (PAAT/PET), right ventricular free wall thickness, and right ventricular hypertrophy index RV/(LV+S). HE staining was performed to observe the lung tissue morphology. EVG staining was performed to observe elastic fiber hyperplasia. Immunohistochemistry was performed to detect α smooth muscle actin (α-SMA) expression in lung tissue. Immunofluorescence staining was used to detect macrophage infiltration in lung tissue. qPCR was performed to detect IL-1β and IL-33 in lung tissue, and cytometric bead array was performed to detect IL-10 secretion. Western blotting was used to detect the M1 macrophage marker iNOS, M2 macrophage marker Arg-1 and IL-33/ST2 pathway proteins in lung tissues. The results showed that hypoxia increased pulmonary artery pressure and pulmonary vascular remodeling, increased macrophage infiltration, IL-1β and IL-33 expression (P < 0.05) and upregulated the IL-33/ST2 pathway (P < 0.05). Compared with the hypoxic group, MSCs-Exo treatment increased PAAT/PET (P < 0.05), decreased right ventricular free wall thickness (P < 0.05), right ventricular hypertrophy index RV/(LV+S) (P < 0.05), α-SMA expression in small pulmonary vessels (P < 0.05), and inflammatory factors including IL-1β and IL-33 expression in lung tissue, however increased IL-10 secretion (P < 0.05). In addition, MSCs-Exo treatment upregulated Arg-1 and downregulated iNOS and IL-33/ST2 (P < 0.05). The results suggest that MSC-Exo may alleviate HPH through their immunomodulatory effects.

Diabetes is a major metabolic disease and health issue worldwide that imposes a heavy burden. Research on its pathogenesis and development of effective treatments are currently our major national demands. With the advent of organoid technology, islet organoids have emerged and are attracting increasing attention as a promising model for diabetes research. The establishment of islet organoids is based on the current understanding of islet development. With addition of extra induction factors in vitro to programmatically activate or inhibit specific signaling pathways during islet development, stem cells can be induced to differentiate into three-dimensional cell cultures that possess structures and functions similar to those of natural islets. Because of their capability to mimic the development of islets in vitro, faithfully replicate islet structure, and perform islet physiological functions, islet organoids have been widely used as a valuable tool for the investigation of diabetes pathogenesis, drug screening and evaluation, and clinical transplantation, showing a great potential application. This paper reviews the current research progress, application, and challenges of islet organoids, and discusses the future directions for research on islet organoids.

Autophagy is a metabolic process in which damaged organelles, obsolete proteins, excess cytoplasmic components, and even pathogens are presented to lysosomes for degradation via autophagosomes. It includes 4 processes: the initiation of autophagy, the formation of autophagosomes, the fusion of autophagosomes with lysosomes, and the degradation and removal of autophagic substrates within autophagic lysosomes. When these processes are continuous, it is called autophagy flux. Blockage of one or certain steps in the autophagy/lysosome signaling pathway can lead to impaired autophagy flux. Numerous studies have shown that impaired autophagy flux is an important cause of neuronal damage in the ischemic penumbra after stroke. This paper summarized research progress in the pathological mechanisms that cause impaired neuronal autophagy flux after ischemic stroke and discusses methods to improve neuronal autophagy flux, in order to provide a reference for an in-depth investigation of the pathological injury mechanisms after stroke.

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive impairment. The main hypotheses about the pathogenesis of AD include the hypothesis of β-amyloid protein, the hypothesis of abnormal phosphorylation of Tau protein, and the hypothesis of neuroinflammation. In recent years, environmental pollutants have been considered as an important factor in causing neurological dysfunction. Common environmental pollutants include heavy metals, pesticides, polychlorinated biphenyls, microplastics, and air pollutants, all of which have been proven to have neurotoxicity. In this review, we not only discussed epidemiological and animal experimental studies that link environmental pollution with AD, but also summarized the mechanisms of action of relevant toxins, providing insights for studying the interrelationships between environmental pollutants and AD.

As a member of the apolipoprotein C (ApoC) family with a relatively high content, ApoC3 plays a major role in the regulation of triglyceride metabolism, and plays an important role in the occurrence and development of cardiovascular diseases, glucose and lipid metabolism disorders. Nonalcoholic fatty liver disease (NAFLD) refers to the accumulation of a large amount of fat in the liver in the absence of a history of chronic alcohol consumption or other damage to the liver. A large number of previous studies have shown that there is a correlation between the gene polymorphism and high expression of ApoC3 and NAFLD. In the context of hypertriglyceridemia (HTG), this article reviews the relationship between ApoC3 and NAFLD, glucose and lipid metabolism, and islet β cell function, showing that ApoC3 can not only inhibit lipoprotein lipase (LPL) and hepatic lipase (HL) activity, delay the decomposition of triglyceride in plasma to maintain the body's energy metabolism during fasting, but also be significantly increased under insulin resistance, prompting the liver to secrete a large amount of very low-density lipoprotein (VLDL) to induce HTG. Therefore, targeting and inhibiting ApoC3 might become a new approach to treat HTG. Increasing evidence suggests that ApoC3 does not appear to be an independent "contributor" to NAFLD. Similarly, our previous studies have shown that ApoC3 is not an independent factor triggering islet β cell dysfunction in ApoC3 transgenic mice, but in a state of excess nutrition, HTG triggered by ApoC3 high expression may exacerbate the effects of hyperglycemia and insulin resistance on islet β cell function, and the underlying mechanism remains to be further discussed.

The present study aims to establish comprehensive evaluation models of physical fitness of the elderly based on machine learning, and provide an important basis to monitor the elderly's physique. Through stratified sampling, the elderly aged 60 years and above were selected from 10 communities in Nanchang City. The physical fitness of the elderly was measured by the comprehensive physical assessment scale based on our previous study. Fuzzy neural network (FNN), support vector machine (SVM) and random forest (RF) models for comprehensive physical evaluation of the elderly people in communities were constructed respectively. The accuracy, sensitivity and specificity of the comprehensive physical fitness evaluation models constructed by FNN, SVM and RF were above 0.85, 0.75 and 0.89, respectively, with the FNN model possessing the best prediction performance. FNN, RF and SVM models are valuable in the comprehensive evaluation and prediction of physical fitness, which can be used as tools to carry out physical evaluation of the elderly.

Chronological aging is the leading risk factor for human diseases, while aging at the cellular level, namely cellular senescence, is the fundamental driving force of organismal aging. The impact of cellular senescence on various life processes, including normal physiology, organismal aging and the progress of various age-related pathologies, has been largely ignored for a long time. However, with recent advancement in relevant fields, cellular senescence has become the core of aging biology and geriatric medicine. Although senescent cells play important roles in physiological processes including tissue repair, wound healing, and embryonic development, they can also contribute to tissue dysfunction, organ degeneration and various pathological conditions during adulthood. Senescent cells exert paracrine effects on neighboring cells in tissue microenvironments by developing a senescence-associated secretory phenotype, thus maintaining long-term and active intercellular communications that ultimately results in multiple pathophysiological effects. This is regarded as one of the most important discoveries in life science of this century. Notably, selective elimination of senescent cells through inducing their apoptosis or specifically inhibiting the senescence-associated secretory phenotype has shown remarkable potential in preclinical and clinical interventions of aging and age-related diseases. This reinforces the belief that senescent cells are the key drug target to alleviate various aging syndromes. However, senescent cells exhibit heterogeneity in terms of form, function and tissue distribution, and even differ among species, which presents a challenge for the translation of significant research achievements to clinical practice in future. This article reviews and discusses the characteristics of senescent cells, current targeting strategies and future trends, providing useful and valuable references for the rapidly blooming aging biology and geriatric medicine.

Aging is an independent risk factor for chronic diseases in the elderly, and understanding aging mechanisms is one of the keys to achieve early prevention and effective intervention for the diseases. Aging process is dynamic and systemic, making it difficult for mechanistic study. With recent advances in aging biomarkers and development of live-imaging technologies, more and more reporter mouse models have been generated, which can live monitor the aging process, and help investigate aging mechanisms at systemic level and develop intervention strategies. This review summarizes recent advances in live-imaging aging reporter mouse models based on widely used aging biomarkers (p16^Ink4a, p21^Waf1/Cip1, p53 and Glb1), and discusses their applications in aging research.