生理学报最新文献

Skin, as the body's largest organ, acts as the primary defense mechanism against infection and injury. The maintenance of skin health heavily relies on the regulation of epidermal stem cells, crucial for ensuring epidermal homeostasis, hair regeneration, and the repair of epidermal injuries. Recent studies have placed a growing emphasis on G protein-coupled receptor (GPCR) in the context of understanding epidermal stem cells, uncovering its significant role in determining their fate. The activation of GPCR triggers the subsequent dissociation of the βγ subunits from the α subunit of G protein, leading to the modulation of various downstream signaling pathways, such as the WNT-BMP signaling crosstalk and the Gαs-PKA signaling pathway. These pathways collectively influence the fate of epidermal stem cells. Consequently, targeted GPCR therapy has emerged as a promising strategy for improving skin health by orchestrating the fate of epidermal stem cells, unveiling potential therapeutic targets that demand further investigation.

Glycine receptors (GlyRs) belong to the ligand-gated ion channel receptor superfamily and are widely distributed throughout the central nervous system. GlyRs are essential for maintaining visual, auditory, sensory and motor functions, and abnormalities in its structure and function can lead to various neurological disorders. This review aims to provide an extensive analysis of the structure, function and regulatory mechanisms of GlyRs, and evaluate its role in various central nervous system diseases. Ultimately, this review will provide theoretical support for the development of novel drugs specifically targeting GlyRs.

Age-related sarcopenia is a degenerative disease characterized by the decline in skeletal muscle mass and function during the aging process. Anabolic resistance, which refers to the diminished response of skeletal muscle to anabolic stimulation from leucine and other nutrients, is a significant contributing factor to its development. Recent studies have suggested that large neutral amino acid-transporter 1 (LAT1/SLC7A5) may play an important role in enhancing leucine's effects on protein synthesis in aging skeletal muscle. In this paper, the structure and function of LAT1 and its key molecules regulating aging skeletal muscle protein synthesis were reviewed, and the potential relationship between LAT1, as a transmembrane transporter of leucine, and protein synthesis in aging skeletal muscle was analyzed. The aim is to explore new mechanisms and insights for prevention and treatment of age-related sarcopenia, and provide reference for the application of relevant targets in clinical translational medicine.

Cancer pain is one of the most common symptoms in patients with advanced cancer. In this study, we aimed to investigate the effects of the Mas-related gene C (MrgC) receptors on bone cancer pain. Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured after the inoculation of Walker 256 mammary gland carcinoma cells into the tibia of adult Sprague-Dawley rats. The effects of MrgC receptor agonist bovine adrenal medulla 8-22 (BAM8-22) on nociceptive behaviors were investigated after intrathecal injection on days 16 and 17. Glial fibrillary acidic protein (GFAP)-positive cells in the spinal dorsal cord, and calcitonin gene related peptide (CGRP)-, neuronal nitric oxide synthase (nNOS)- and IL-1β-positive neurons in the dorsal root ganglia (DRG) were examined by immunofluorescence staining. The expression of nNOS and IL-1β proteins in the spinal dorsal horn and the DRG was examined by Western blotting after treatment with (Tyr6)-γ2-MSH-6-12 (MSH), which was another MrgC receptor agonist. The results showed that intrathecal injection of BAM8-22 (30 nmol) attenuated mechanical allodynia in a rat model of bone cancer pain and the effects could last for about 60 min, and single administration of BAM8-22 for two consecutive days reduced mechanical allodynia by about half on the third day. Moreover, the number of GFAP-positive cells in the spinal dorsal horn, and the number of CGRP-, nNOS- and IL-1β-positive neurons in the DRG were decreased. Similarly, intrathecal administration of MSH (15 nmol) reduced the expression of nNOS and IL-1β in the spinal dorsal horn and the DRG. In conclusion, activation of MrgC receptors suppresses the activation of astrocytes in the spinal dorsal cord and the expression of CGRP, nNOS, and IL-1β in the spinal dorsal cord and/or DRG, which may underlie the inhibition of bone cancer pain. These findings provide a novel strategy for the treatment of bone cancer pain.

The aim of this study was to conduct in vivo experiments using laser speckle contrast imaging (LSCI) technology to investigate the effects of high salt diet on renal vascular reactivity in mice. LSCI is a technology for monitoring blood flow based on the laser speckle principle. It has been widely used to detect microcirculatory functions in tissues such as the skin and brain. The kidneys are located behind the peritoneum, and their position is easily affected by the movement of abdominal organs. Measuring renal microcirculation in a living individual is difficult. The present study used a self-made kidney cup to isolate the kidney and fix its position relatively, and then applied LSCI technology to explore the effect of high salt diet (8% Na⁺) on renal vascular reactivity in male and female mice in vivo. The results showed that a short-term high salt diet (1 week) did not affect the systolic blood pressure of the tail artery, while significantly increased glomerular filtration rate (GFR) and renal blood flow (RBF). Compared with the normal salt diet group, the high salt diet group showed a significant decrease in the ratio of post-occlusive reactive hyperemia (PORH) in male mice, while there was no significant change in the PORH ratio in female mice. These results suggest that, although a short-term high salt diet does not cause changes in blood pressure, it has already affected renal vascular reactivity and has gender differences in its effects. Furthermore, the present study provides a basis for renal microcirculation assessment using LSCI in vivo.

Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid decline in renal function. Renal ischemia-reperfusion injury (RIRI) is one of the main causes of AKI with the underlying mechanism incompletely clarified. The liver X receptors (LXRs), including LXRα and LXRβ, are members of the nuclear receptor superfamily. It has been shown that LXRs play an important role in regulating glucose and lipid metabolism, cholesterol efflux, and inflammation. The purpose of this study was to explore the role and mechanism of LXRs in RIRI. We determined the effects of LXR activation on renal function and histological changes in a mouse RIRI model and a cellular model of hypoxia/reoxygenation (H/R). In vivo results showed that LXRs agonist GW3965 significantly inhibited the increase of serum creatinine and urea nitrogen levels induced by RIRI. Both HE and PAS staining of kidney tissues revealed that GW3965 alleviated the morphological damages caused by RIRI. Immunohistochemical staining showed that GW3965 mitigated 4-HNE and GRP78 levels induced by RIRI. Furthermore, TUNEL assay indicated that GW3965 reduced RIRI-induced renal cell apoptosis. Quantitative real-time PCR (qPCR) analysis revealed that GW3965 attenuated RIRI-induced IL-6 and IL-1β mRNA expression. Compared with wild-type group, LXRα gene deficiency had little effect on RIRI-associated renal functional decline and morphological damages. Additionally, in vitro study demonstrated that GW3965 alleviated H/R-induced decrease of HK-2 human renal proximal tubule cell viability and restored the activity of superoxide dismutase (SOD) after H/R. Western blot results showed that GW3965 mitigated the increase of 4-HNE and GRP78 protein expression levels after H/R; However, knockdown of LXRβ using the small interfering RNA (siRNA) technique reduced cell viability compared to GW3965-treated group. Taken together, the LXRs agonist GW3965 significantly alleviates RIRI in mice possibly by reducing apoptosis, oxidative stress, endoplasmic reticulum stress and inflammation. These results also preliminarily confirm that the renal protective effects of LXRs agonists are dependent on LXRβ.

The objective of the present study was to investigate the role and mechanism of bone marrow microenvironmental cells in regulating the mitochondrial mass of leukemia cells, and to uncover the mechanism of leukemia progression at the metabolic level. A mouse model of acute myeloid leukemia (AML) induced by the overexpression of the MLL-AF9 (MA9) fusion protein was established, and the bone marrow cells of AML mice were transplanted into mitochondrial fluorescence reporter mice expressing the Dendra2 protein (mito-Dendra2 mice). The proportion of Dendra2⁺ cells in bone marrow leukemia cells at different stages of AML was quantified by flow cytometry. The effects of transferred mitochondria on leukemia cells were studied by fluorescence-activated cell sorting (FACS), followed by functional experiments and bulk RNA sequencing. Finally, components within the bone marrow niche, such as mesenchymal stromal cells (MSCs) and endothelial cells (ECs), were co-cultured with leukemia cells in vitro. The proportion of leukemia cells that underwent mitochondrial transfer and the apoptosis level of leukemia cells were then detected by flow cytometry. The results showed that mitochondria from bone marrow cells were transferred to leukemia cells in the AML mouse model, and the proportion of mitochondrial transfer decreased with AML progression. The proportion of mitochondria transferred to leukemia stem cells (LSCs) was lower than that of mature AML cells. In AML cells receiving Dendra2⁺ mitochondria, there was a significant increase in the levels of intracellular reactive oxygen species (ROS) and apoptosis, while the levels of protein translation and their colony-forming capacities were decreased. The transplantation of Dendra2⁺ AML cells resulted in an extension of the survival of mice. RNA sequencing analysis demonstrated a significant downregulation of pathways related to translation, aerobic respiration and mitochondrial organization in AML cells that had received mitochondria. In vitro co-culture experiments indicated that MSCs within the bone marrow niche tended to transfer their mitochondria to leukemia cells and promoted the apoptosis of leukemia cells. These results indicate that in the MA9-induced AML mouse model, bone marrow niche cells can transfer mitochondria to leukemia cells, resulting in a reduction in the overall survival and function of the leukemia cells. Mitochondrial transfer in the bone marrow microenvironment may serve as a self-defensive mechanism of the host bone marrow niche cells, inhibiting the progression of AML.

N6-methyladenosine (m⁶A) is the most common type of RNA modification in eukaryotes, which affects intracellular RNA metabolism and controls gene expression of related pathophysiological processes through dynamic reversible regulation of methyltransferases, demethylases and m⁶A-binding proteins. In recent years, the involvement of m⁶A methylation in the study of neuropathic pain has become a hot topic, some new understandings have been emerging, and m⁶A methylation has become a potential biological target for the treatment of neuropathic pain. Therefore, this article reviews the role and regulation of m⁶A methylation in neuropathic pain, in order to provide new enlightenment for the drug development and treatment of neuropathic pain.

Adipose tissue holds a pivotal position in maintaining systemic energy homeostasis. Brown adipose tissue (BAT) expresses uncoupling protein 1 (UCP1), which is specialized in dissipating chemical energy as heat to maintain euthermia, a process called non-shivering thermogenesis. Conversely, white adipocyte (WAT) predominantly serves as the primary reservoir for energy storage, while also exhibiting endocrine activity by secreting various adipokines, thereby modulating systemic metabolism. Under the stimulation of cold exposure, physical activity and pharmacological intervention, WAT can occur as "browning" or "beiging", and transform into beige adipose tissue. The morphology and function of beige adipocyte are similar to brown adipocyte, both of which express higher levels of UCP1 and also have the function of thermogenesis. Thus, exploring methods to regulate the functional homeostasis of adipose tissue and its underlying molecular mechanisms hold promise for advancing preventative and therapeutic approaches against metabolic diseases. Exosomes, a subtype of extracellular vesicles (EVs) with a diameter of 40-100 nm, facilitate intercellular communication in obese individuals and exert significant influence on insulin resistance and impaired glucose tolerance within adipose tissue. These effects are primarily mediated by microRNA (miRNA) transported by exosomes. MiRNA, originating from various cellular sources, traverses between different cell types via EVs, thereby orchestrating reciprocal functional modulation among diverse tissues and organs. This review systematically summarized the research progress in exosomal miRNA-mediated regulation of adipose tissue functional homeostasis, with the aim of offering novel insights into the diagnosis and treatment of obesity and associated metabolic diseases.

The etiology of rheumatoid arthritis (RA), a chronic inflammatory systemic disease, remains unclear. It is characterized by symmetrical and invasive joint inflammation, primarily affecting distal small joints such as those in the hands and feet. This inflammation can lead to joint deformity and loss of function, and often accompanied by involvement of extra-articular organs like the lungs and heart. Currently, anti-rheumatic drugs only provide symptom improvement but have toxic side effects that require optimization. Therefore, it is crucial to thoroughly analyze the mechanisms underlying RA development for the identification of new drug targets. Programmed cell death (PCD) has been extensively studied in recent years and proved to be one of the key pathogenic factors in RA. Dysregulation of PCD is particularly evident in synoviocytes, immune cells, and osteocytes. This review summarizes various forms of PCD including apoptosis, NETosis, autophagy, pyroptosis, necroptosis, ferroptosis, cuproptosis, as well as their regulatory roles in fibroblast synoviocytes, immune cells and osteocytes. These findings hold significant theoretical implications for optimizing clinical treatment options for RA and developing new target drugs.