PGC-1alpha, SIRT1 and AMPK, an energy sensing network that controls energy expenditure

Study on the regulation of renal tubular cell apoptosis by SIRT1/NF-κB signaling pathway in septic acute kidney injury

SIRT1 regulates gene transcription via various signaling pathways, mitigating oxidative stress damage in renal tubular epithelial cells, reducing renal inflammation, and decreasing apoptosis in tubular cells. This study explores the mechanisms of action of SIRT1 in sepsis-induced acute kidney injury (AKI), offering a theoretical foundation for future treatments. Experiments were carried out in a CLP mouse model and an in vitro model using LPS-stimulated HK-2 cells. Immunoblotting and ELISA were employed to assess the expression levels of inflammatory cytokines (p < 0.01), finding that SIRT1 effectively reduces the inflammatory response in sepsis-induced AKI. Moreover, the detection of cell apoptosis via multiple pathways showed that SIRT1 can reduce the rate of cell apoptosis and effectively decrease oxidative stress in the validation reaction. Transmission electron microscopy observations further supported these findings, demonstrating that SIRT1 expression induces the blockade of cell apoptosis processes. The biochemical experiments concluded that SIRT1 ameliorates sepsis-induced AKI. Consequently, SIRT1 may represent a novel therapeutic target for AKI.

Mitophagy in Alzheimer's disease and other metabolic disorders: A focus on mitochondrial-targeted therapeutics

Mitochondria, as central regulators of cellular processes such as energy production, apoptosis, and metabolic homeostasis, are essential to cellular function and health. The maintenance of mitochondrial integrity, especially through mitophagy-the selective removal of impaired mitochondria-is crucial for cellular homeostasis. Dysregulation of mitochondrial function, dynamics, and biogenesis is linked to neurodegenerative and metabolic diseases, notably Alzheimer's disease (AD), which is increasingly recognized as a metabolic disorder due to its shared pathophysiologic features: insulin resistance, oxidative stress, and chronic inflammation. In this review, we highlight recent advancements in pharmacological interventions, focusing on agents that modulate mitophagy, mitochondrial uncouplers that reduce oxidative phosphorylation, compounds that directly scavenge reactive oxygen species to alleviate oxidative stress, and molecules that ameliorate amyloid beta plaque accumulation and phosphorylated tau pathology. Additionally, we explore dietary and lifestyle interventions-MIND and ketogenic diets, caloric restriction, physical activity, hormone modulation, and stress management-that complement pharmacological approaches and support mitochondrial health. Our review underscores mitochondria's central role in the pathogenesis and potential treatment of neurodegenerative and metabolic diseases, particularly AD. By advocating for an integrated therapeutic model that combines pharmacological and lifestyle interventions, we propose a comprehensive approach aimed at mitigating mitochondrial dysfunction and improving clinical outcomes in these complex, interrelated diseases.

Is SIRT3 and Mitochondria a Reliable Target for Parkinson's Disease and Aging? A Narrative Review

Aging is a complicated degenerative process that has been thoroughly researched in a variety of taxa, including mammals, worms, yeast, and flies. One important controller of organismal lifetime is the conserved deacetylase protein known as silencing information regulator 2 (SIR2). It has been demonstrated that overexpressing SIR2 lengthens the life span in worms, flies, and yeast, demonstrating its function in enhancing longevity. SIRT3 is a member of the sirtuin protein family, identified as a major regulator of longevity and aging. Sirtuin 3 (SIRT3), a possible mitochondrial tumor suppressor, has been explicitly linked to the control of cellular reactive oxygen species (ROS) levels, the Warburg effect, and carcinogenesis. SIRT3 plays a significant part in neurodegenerative illnesses such as Parkinson's and Alzheimer's disease by decreasing the oxidative stress in mitochondria and reducing the ROS levels. Furthermore, SIRT3 has been linked to metabolic and cardiovascular disorders, indicating its wider role in the pathophysiology of disease and possible therapeutic applications.

Unsaturated fatty acids enhance mitochondrial function and PGC1-α expression in brown adipose tissue of obese mice on a low-carbohydrate diet

Brown adipose tissue (BAT) exhibits greater resilience against inflammation compared to white adipose tissue. However, chronic consumption of a high-fat diet can render brown adipocytes vulnerable to proinflammatory conditions, leading to a decline in their thermogenic capacity and subsequent dysfunction. The analysis of the effects of type fatty acids intake must be important in the context of the dietary pattern and obesity. This study aims to investigate the impact of a low-carbohydrate/high-fat diet, enriched with different types of fatty acids, on mitochondrial activity on brown adipose tissue in obese mice. Male mice were allocated into different dietary groups: a control diet (CTL), and a high-fat diet (HFD) for a duration of 10 weeks to induce obesity. Subsequently, the HFD group was subdivided into the following categories for an additional 6 weeks: HFD with a low carbohydrate content enriched with saturated fatty acids; HFD with a low carbohydrate content enriched with fish oil; HFD with a low carbohydrate content enriched with soybean oil; and HFD with a low carbohydrate content enriched with olive oil. The findings indicated that in comparison to a low-carbohydrate diet rich in saturated fats, diets rich in unsaturated fatty acids-particularly omega-6 (n-6) and omega-9 (n-9)-resulted in elevated expression of UCP1, a marker of BAT activity. Moreover, there was an increase in the expression of PGC1-α, a protein involved in mitochondrial biogenesis, and enhanced functionality of the oxidative phosphorylation system within BAT mitochondria. These results suggest that n-6 and n-9 fatty acids may confer greater benefits to BAT functionality than saturated fats within the context of a low-carbohydrate diet. Therefore, this study revealed some molecular components that mediate BAT mitochondria function influenced by different fatty acids in a low carbohydrate diet, making it an important therapeutic target in obesity.

Platelet Extracellular Vesicles as Natural Delivery Vehicles for Mitochondrial Dysfunction Therapy?

Mitochondria are vital for energy production, metabolic regulation, and cellular signaling. Their dysfunction is strongly implicated in neurological, cardiovascular, and muscular degenerative diseases, where energy deficits and oxidative stress accelerate disease progression. Platelet extracellular vesicles (PEVs), once called "platelet dust", have emerged as promising agents for mitigating mitochondrial dysfunction. Like other extracellular vesicles (EVs), PEVs carry diverse molecular cargo and surface markers implicated in disease processes and therapeutic efficacy. Notably, they may possibly contain intact or partially functional mitochondrial components, making them tentatively attractive for targeting mitochondrial damage. Although direct research on PEVs-mediated mitochondrial rescue remains limited, current evidence suggests that PEVs can modulate diseases associated with mitochondrial dysfunction and potentially enhance mitochondrial health. This review explores the therapeutic potential of PEVs in neurodegenerative and cardiovascular disorders, highlighting their role in restoring mitochondrial health. By examining recent advancements in PEVs research, we aim to shed light on novel strategies for utilizing PEVs as therapeutic agents. Our goal is to underscore the importance of further fundamental and applied research into PEVs-based interventions, as innovative tools for combating a wide range of diseases linked to mitochondrial dysfunction.

Calorie-restriction treatment mitigates the aging in rat liver model

The aging process promotes progressive impairment of homeostasis and the increase of the risk of disease and death. A major hallmark of the aging process is the systemic chronic inflammation which strongly contributes to the onset of aging-related diseases. In the liver, the aging condition drives the hepatocytes to develop a metabolic dysfunction-associated steatosis. Caloric restriction (CR) is a remarkable strategy to delay biological aging, occurring through several mechanisms. In this study we aimed to explore, employing an in vivo rat model, the impact of CR on aging-mediated liver inflammation markers. The experiments were performed on 14 male Sprague-Dawley rats (24 months old). At 18 months old, rats were allocated into two groups: the normal diet (ND) group was continued ad libitum diet, and the CR regimen group was fed a diet of the same chow restricted to 60% of the intake. All animals were sacrificed at 24 months old. Compared to the ND group, morphological examination of the liver revealed a lower level of fibrosis in the CR group, concomitantly with a reduced expression of key fibrotic markers, such as collagen I, fibronectin, and αSMA. Furthermore, CR improved the liver oxidative balance, as showed by the increased expression of two scavenging enzymes, SOD1/SOD. Moreover, we reported concomitant reduction of NLRP3 inflammasome signalling. Interestingly, CR significantly improved the signalling of key members of the nutrition-sensitizing affected by aging, AMPK/SIRT1/LKB1. Collectively our findings support the evidence on the metabolic benefits of CR about aging-related liver inflammation, by inducing a morphological improvement that mirrors the decrease in the expression of inflammatory molecular markers.

Organ dysfunction induced by hemorrhagic shock: From mechanisms to therapeutic medicines

Hemorrhagic shock (HS) leads to organ dysfunction, which increases the incidence of unfavorable outcomes in patients. However, adjuvant drug therapy for HS has not been widely accepted, and the benefits of vasopressors are generally considered to have insufficient evidence. Energy homeostasis disruption and excessive immune system activation are the main mechanisms underlying HS-induced organ dysfunction. Recent reports on HS animal models and clinical trials have revealed potential drugs that target the immune response, oxidative damage, and energy homeostasis in HS, providing new insights for the treatment of HS-induced organ dysfunction. In this review, we first discuss the pathophysiology of organ dysfunction involved in HS injury and then systematically review potential drugs that regulate immunity, the inflammatory response, oxidative damage, energy homeostasis, and cell death. We also review the available drugs with clinical evidence of HS-induced organ dysfunction efficacy. Treatment strategies combined with an improved understanding of the organ injury mechanisms of HS may help identify and develop targeted therapeutic modalities that mitigate severe organ dysfunction and reduce mortality caused by HS injury.

Lactucin and lactucopicrin ameliorate obesity in high-fat diet fed mice by promoting white adipose tissue browning through the activation of the AMPK/SIRT1/PGC-1α pathway

Lactucin and lactucopicrin are the characteristic lipid-lowering active components found in Cichorium glandulosum. However, their effects and underlying mechanisms in obesity remain unclear. In the present study, C57BL/6J mice were simultaneously subjected to a high-fat diet (HFD) and treated with drugs to investigate the impacts of lactucin and lactucopicrin on HFD-induced obese mice. The results demonstrated that in HFD obese mice, lactucin and lactucopicrin significantly decreased body weight and the weights of adipose tissues, improved serum metabolic parameters, and increased the content of irisin. Regarding the intermediate metabolites of intestinal flora, which are closely associated with white adipose tissue (WAT) browning, lactucin and lactucopicrin treatment led to a reduction in the levels of 12-α-OH/non-12-α-OH bile acids (BAs) and also tended to enhance the levels of short-chain fatty acids (SCFAs). qRT-PCR results indicated that lactucin and lactucopicrin treatment elevated the expression levels of genes related to beige fat markers, thermogenesis, mitochondrial biogenesis, and lipolysis in WAT, as well as those of thermogenesis and lipolysis genes in brown adipose tissue (BAT). Western blot analysis revealed that lactucin and lactucopicrin up-regulated the expression of uncoupling protein 1 (UCP1), the core protein in thermogenesis, in both WAT and BAT. Moreover, they also up-regulated the expression levels of AMP-activated kinase (AMPK), sirtuin 1 (SIRT1), and PPARγ coactivator 1-alpha (PGC-1α), which are key pathway proteins involved in WAT browning. Furthermore, 16S rRNA sequencing results showed that in HFD obese mice, lactucin and lactucopicrin improved the composition and function of the intestinal microbiota. In conclusion, lactucin and lactucopicrin may promote WAT browning by activating the AMPK/SIRT1/PGC-1α pathway, thereby ameliorating obesity in HFD mice.

Targeting AMPK as a potential treatment for hepatic fibrosis in MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease, and often progresses to hepatic fibrosis, cirrhosis, and liver failure. Despite its increasing prevalence, effective pharmacological treatments for MASLD-related fibrosis remain limited. Recent research has highlighted AMP-activated protein kinase (AMPK) as a key regulator of the processes that promote fibrogenesis, and AMPK activation shows potential in mitigating fibrosis. Advances in AMPK activators and deeper insights into their role in fibrotic pathways have recently revitalized interest in targeting AMPK for fibrosis treatment. This review discusses the molecular mechanisms linking AMPK to hepatic fibrosis and evaluates emerging AMPK-directed therapies. Furthermore, it addresses challenges in clinical translation. Importantly, we combine the latest mechanistic discoveries with recent therapeutic developments to provide a comprehensive perspective on AMPK as a target for hepatic fibrosis treatment.

Myocellular adaptations to short-term weighted wheel-running exercise are largely conserved during C26-tumour induction in male and female mice

This study investigated whether performing a translatable murine model of concurrent training after tumour induction affects adaptations in juvenile male and female tumour-bearing mice. Male and female Balb/c mice were injected bilaterally with colon-26 adenocarcinoma (C26) cells or PBS at 8 weeks of age. Half the mice then performed 24 days of voluntary wheel running with progressively increased load (PoWeR training), whereas the rest remained sedentary. Deuterium oxide-based protein synthesis, muscle fibre-type composition and size, protein turnover and mitochondrial markers were assessed 25 days after tumour induction. Average gastrocnemius muscle fibre size was smaller with PoWeR regardless of tumour in males and females, concomitant with a pronounced faster-to-slower fibre-type transition. In male tumour-bearing mice, PoWeR training resulted in greater Redd1, Murf1 and Pgc1α mRNA content than all the other groups, along with lower overall running volume, food consumption and protein synthesis relative to control animals. Molecular measures followed a similar pattern in tumour-bearing female mice with PoWeR, but food consumption, running volume and muscle protein synthesis were maintained. PoWeR training lowered gonadal fat during cancer cachexia in both sexes, and greater heart weight was observed regardless of tumour presence. A negative correlation was found between tumour weight and running distance. Collectively, PoWeR has a similar effect on muscle cellular phenotype in both sexes regardless of tumour presence, and a training effect in male mice with cancer cachexia was present despite molecular and protein synthesis dysregulation.

High-Resolution Tracking of Aging-Related Small Molecules: Bridging Pollutant Exposure, Brain Aging Mechanisms, and Detection Innovations

Brain aging is a complex process regulated by genetic, environmental, and metabolic factors, and increasing evidence suggests that environmental pollutants can significantly accelerate this process by interfering with oxidative stress, neuroinflammation, and mitochondrial function-related signaling pathways. Traditional studies have focused on the direct damage of pollutants on macromolecules (e.g., proteins, DNA), while the central role of senescence-associated small molecules (e.g., ROS, PGE2, lactate) in early regulatory mechanisms has been long neglected. In this study, we innovatively proposed a cascade framework of "small molecule metabolic imbalance-signaling pathway dysregulation-macromolecule collapse", which reveals that pollutants exacerbate the dynamics of brain aging through activation of NLRP3 inflammatory vesicles and inhibition of HIF-1α. Meanwhile, to address the technical bottleneck of small molecule spatiotemporal dynamics monitoring, this paper systematically reviews the cutting-edge detection tools such as electrochemical sensors, genetically encoded fluorescent probes and antioxidant quantum dots (AQDs). Among them, AQDs show unique advantages in real-time monitoring of ROS fluctuations and intervention of oxidative damage by virtue of their ultra-high specific surface area, controllable surface modification, and free radical scavenging ability. By integrating multimodal detection techniques and mechanism studies, this work provides a new perspective for analyzing pollutant-induced brain aging and lays a methodological foundation for early intervention strategies based on small molecule metabolic networks.

Withania somnifera Regulates Mitochondrial Biogenesis and Energetics in Rat Cortical Neurons: Role of BDNF and SIRT1

Withania somnifera, a psychoactive plant with putative neuroprotective actions, is used in Indian traditional medicine for the treatment of neuropsychiatric and neurodegenerative disorders. However, the key mechanisms underlying the pleiotropic actions of Withania somnifera on the nervous system remain poorly understood. Given converging evidence suggests a critical role for mitochondrial dysfunction in the pathophysiology of neuropsychiatric and neurodegenerative diseases, we hypothesized that Withania somnifera may exert pleiotropic effects via targeting mitochondria. Treatment with Withania somnifera root extract (RE) or the withanolide-withanoside rich fraction (WLS) enhanced cellular ATP levels in rat cortical neurons in vitro and in the neocortex in vivo. In vivo respirometry performed on mitochondria isolated from the neocortex following RE or WLS treatment revealed increased mitochondrial respiration and OxPhos efficiency. Furthermore, WLS treatment evoked increases in mitochondrial mass, and RE and WLS treatments enhanced expression of brain derived neurotrophic factor (BDNF) and Sirtuin 1 (SIRT1), both in vitro and in vivo. Pharmacological inhibitor studies support an important role for BDNF and SIRT1 in the mitochondrial effects of Withania somnifera. Experiments with distinct phytochemical components of WLS identified withanolide A and withanoside IV as key constituents that enhance mitochondrial biogenesis and neuroenergetics. The neuroprotective actions of WLS, withanolide A and withanoside IV against corticosterone-induced neuronal cell death in vitro, required signaling via BDNF and SIRT1. Collectively, these results indicate that Withania somnifera root extract and specific phytochemical constituents robustly influence mitochondria in cortical neurons, contributing to stress adaptation and neuroprotection via BDNF and SIRT1 signaling.

Polygala fallax Hemsl. ameliorated high glucose-induced podocyte injury by modulating mitochondrial mPTP opening through the SIRT1/PGC-1α pathway

This study aimed to investigate the effects and molecular mechanism of PF on high glucose (HG)-induced podocyte injury. Results found that PF increased proliferation activity, decreased apoptosis, LDH, and caspase-3 levels, and increased nephrin and podocin expression in HG-induced cells. Similarly, PF improved HG-induced mitochondrial damage, decreased Ca2+ and ROS content, alleviated oxidative stress, inhibited mPTP opening, increased mitochondrial membrane potential, and decreased the expressions of Drp1, Bak, Bax, and Cytc in cytoplasm, increased the expressions of SIRT1, PGC-1α, HSP70, HK2, and Cytc in mitochondria of podocytes. The use of mPTP agonist/blocker and SIRT1 inhibitor confirmed that PF alleviates HG-induced podocyte injury by regulating mitochondrial mPTP opening through SIRT1/PGC-1α. In addition, PF affected HK2-VDAC1 protein binding to regulate mPTP opening via the SIRT1/PGC-1α pathway. In conclusion, PF-regulated HK2-VDAC1 protein binding affected mitochondrial mPTP opening and improved HG-induced podocyte injury through the SIRT1/PGC-1α pathway.

Polyplex Nanomicelle-Mediated Pgc-1α4 mRNA Delivery Via Hydrodynamic Limb Vein Injection Enhances Damage Resistance in Duchenne Muscular Dystrophy Mice

Duchenne muscular dystrophy (DMD) is caused by mutations in the DMD gene, leading to the absence of dystrophin and progressive muscle degeneration. Current therapeutic strategies, such as exon-skipping and gene therapy, face limitations including truncated dystrophin production and safety concerns. To address these issues, a novel mRNA-based therapy is explored using polyplex nanomicelles to deliver mRNA encoding peroxisome proliferator-activated receptor gamma coactivator 1 alpha isoform 4 (PGC-1α4) via hydrodynamic limb vein (HLV) administration. Using an in vivo muscle torque measurement technique, it is observed that nanomicelle-delivered Pgc-1α4 mRNA significantly improved muscle damage resistance and mitochondrial activity in mdx mice. Specifically, HLV administration of Pgc-1α4 mRNA in dystrophic muscles significantly relieved the torque reduction and myofiber injury induced by eccentric contraction (ECC), boosted metabolic gene expression, and enhanced muscle oxidative capacity. In comparison, lipid nanoparticles (LNPs), a widely used mRNA delivery system, does not achieve similar protective effects, likely due to their intrinsic immunogenicity. This foundational proof-of-concept study highlights the potential of mRNA-based therapeutics for the treatment of neuromuscular diseases such as DMD and demonstrates the capability of polyplex nanomicelles as a safe and efficient mRNA delivery system for therapeutic applications.

Examining a role for irisin in treating cerebral ischemia

Stroke is a leading cause of death and disability, with ischemic stroke representing most cases. Age is the most significant nonmodifiable risk factor for stroke, and with an aging population, there is an urgent need for effective prevention and treatment strategies. Physical inactivity is a strong risk factor for stroke, and exercise has long been held as a promising approach to improve poststroke outcomes. During exercise, the myokine irisin is released as a product of a type 1 membrane protein cleavage that is encoded by the fibronectin type III domain containing 5 (FNDC5) gene. This review summarizes recent literature on irisin's role in ischemic stroke, examining central effects, stroke risk, poststroke functional outcomes, and exogenous administration. Irisin has value as a prognostic marker for risk stratification. Low levels of irisin correlate with worse outcomes and higher mortality in patients with ischemic stroke. Irisin may also be a key to the benefits of exercise, particularly for high-intensity resistance training, which significantly increases irisin levels. Beyond exercise, exogenous irisin is neuroprotective in murine models, reducing brain edema, inflammation, and apoptosis, and increasing blood-brain barrier integrity and brain-derived neurotrophic factor levels. This underscores irisin's potential to mitigate ischemic damage and promote recovery. Human trials are necessary to validate these findings and explore the feasibility of irisin-based interventions in acute stroke care. This review lays a foundation for future research to clarify irisin's therapeutic benefits, establish optimal exercise protocols, and explore exogenous irisin as a novel intervention for ischemic stroke.

Metabolic Reprogramming in Stromal and Immune Cells in Rheumatoid Arthritis and Osteoarthritis: Therapeutic Possibilities

Metabolic reprogramming of stromal cells, including fibroblast-like synoviocytes (FLS) and chondrocytes, as well as osteoclasts (OCs), are involved in the inflammatory and degenerative processes underlying rheumatoid arthritis (RA) and osteoarthritis (OA). In RA, FLS exhibit mTOR activation, enhanced glycolysis and reduced oxidative phosphorylation, fuelling inflammation, angiogenesis, and cartilage degradation. In OA, chondrocytes undergo metabolic rewiring, characterised by mTOR and NF-κB activation, mitochondrial dysfunction, and increased glycolysis, which promotes matrix metalloproteinase production, extracellular matrix (ECM) degradation, and angiogenesis. Macrophage-derived immunometabolites, including succinate and itaconate further modulate stromal cell function, acting as signalling molecules that modulate inflammatory and catabolic processes. Succinate promotes inflammation whilst itaconate is anti-inflammatory, suppressing inflammatory joint disease in models. Itaconate deficiency also correlates inversely with disease severity in RA in humans. Emerging evidence highlights the potential of targeting metabolic processes as promising therapeutic strategies for connective tissue disorders.

Thermogenesis and Energy Metabolism in Brown Adipose Tissue in Animals Experiencing Cold Stress

Cold exposure is a regulatory biological functions in animals. The interaction of thermogenesis and energy metabolism in brown adipose tissue (BAT) is important for metabolic regulation in cold stress. Brown adipocytes (BAs) produce uncoupling protein 1 (UCP1) in mitochondria, activating non-shivering thermogenesis (NST) by uncoupling fuel combustion from ATP production in response to cold stimuli. To elucidate the mechanisms underlying thermogenesis and energy metabolism in BAT under cold stress, we explored how cold exposure triggers the activation of BAT thermogenesis and regulates overall energy metabolism. First, we briefly outline the precursor composition and function of BA. Second, we explore the roles of the cAMP- protein kinase A (PKA) and adenosine monophosphate-activated protein kinase (AMPK) signaling pathways in thermogenesis and energy metabolism in BA during cold stress. Then, we analyze the mechanism by which BA regulates mitochondria homeostasis and energy balance during cold stress. This research reveals potential therapeutic targets, such as PKA, AMPK, UCP1 and PGC-1α, which can be used to develop innovative strategies for treating metabolic diseases. Furthermore, it provides theoretical support for optimizing cold stress response strategies, including the pharmacological activation of BAT and the genetic modulation of thermogenic pathways, to improve energy homeostasis in livestock.

Preliminary Evidence Suggests That a 12-Week Treatment with Tirzepatide Plus Low-Energy Ketogenic Therapy Is More Effective than Its Combination with a Low-Calorie Diet in Preserving Fat-Free Mass, Muscle Strength, and Resting Metabolic Rate in Patients with Obesity

Background: Tirzepatide (TZP), a unimolecular dual agonist targeting glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors, is a promising weight loss agent in obesity. The preservation of metabolically active fat-free mass (FFM), muscle strength (MS), and resting metabolic rate (RMR) is essential for optimizing fat mass (FM) reduction. Although TZP is typically combined with a low-calorie diet (LCD), its impact on FFM is uncertain, and studies on MS and RMR are lacking. Evidence suggests that Low-Energy Ketogenic Therapy (LEKT) may reduce FM while preserving FFM, MS, and RMR. Therefore, this study aimed to compare the effects of an LEKT and an LCD, both combined with TZP, on body weight (BW), FM, FFM, MS, and RMR in patients with obesity. Methods: We prospectively compared the effects of TZP combined with either an LCD or LEKT in 60 patients with obesity (n = 30 per group) over 12 weeks. BW, FM, FFM, MS, and RMR were measured at baseline and after 12 weeks. Clinical parameters, an assessment of dietary compliance, and side effects were also evaluated. Results: At 12-week follow-up, both groups showed a significant BW reduction from baseline (TZP+LEKT, p = 0.0289; TZP+LCD, p = 0.0278), with no significant intergroup difference (p = 0.665). Similarly, FM decreased significantly in both cohorts (TZP+LEKT, p < 0.001; TZP+LCD, p = 0.0185), with the TZP+LEKT group achieving a greater FM loss (p = 0.042). However, the TZP+LCD group exhibited significant declines from baseline in FFM (p = 0.0284), MS (p = 0.0341), and RMR (p < 0.001), whereas we did not observe any significant changes in FFM (p = 0.487), MS (p = 0.691), and RMR (p = 0.263) in the TZP+LEKT group. Intergroup direct comparisons confirmed that the TZP+LCD group experienced significantly greater reductions in FFM (p = 0.0388), MS (p = 0.046), and RMR (p = 0.019). Conclusions: Based on the findings of these preliminary data, we are able to support the hypothesis that TZP+LEKT seems to be superior to TZP+LCD in promoting FM reduction while preserving FFM, MS, and RMR in patients with obesity.

Dual Action of Pueraria montana var. lobata Extract on Myogenesis and Muscle Atrophy

Background/Objectives: Muscle atrophy, defined by diminished muscle mass and function, is a notable concern associated with aging, disease, and glucocorticoid treatment. Pueraria montana var. lobata extract (PMLE) demonstrates multiple bioactive properties, such as antioxidant, anti-inflammatory, and metabolic regulatory activities; however, its role in muscle atrophy has not been extensively investigated to date. This study examined how PMLE influences both muscle cell differentiation and dexamethasone (DEX)-induced muscle degeneration by focusing on the underlying molecular mechanisms. Methods: This study examined the effects of PMLE on myogenic differentiation and DEX-induced muscle atrophy. C2C12 myoblasts were treated with PMLE (10-100 ng/mL) and assessed for changes in the expression of myogenesis-related genes and activation of Akt/mTOR and AMPK/SIRT1/PGC-1α signaling cascades. In vivo, a DEX-induced muscle atrophy model was used to assess muscle mass, fiber morphology, and molecular changes. Results: PMLE PMLE promoted muscle cell development by increasing the expression of MyHC, MyoD, and myogenin while activating protein synthesis and mitochondrial biogenesis pathways. PMLE counteracted DEX-induced myotube atrophy, restoring myotube diameter and promoting cellular fusion in vitro. In vivo, PMLE mitigated muscle degradation in fast-twitch muscle groups and reversed DEX-induced suppression of key anabolic and mitochondrial pathways. Conclusions: These findings suggest that PMLE promotes myogenic differentiation and protects against muscle atrophy by regulating critical molecular pathways, indicating its promise as a treatment candidate for conditions involving muscle wasting. Further studies are required to assess its clinical application and long-term safety efficacy.

Estradiol activates the CaMKKβ/AMPK pathway to enhance neurite outgrowth in cultured adult sensory neurons

Adult rat dorsal root ganglion (DRG) sensory neurons express estrogen receptors (ERs) α and β. Estrogen regulates multiple aspects of the nervous system including development, survival, and axonal outgrowth of DRG neurons. While previous studies have established estrogen's neuroprotective role in these neurons, the specific ER subtypes and downstream signaling pathways mediating these effects remain poorly defined. The objective of our study was to investigate the effects of 17 beta-estradiol (E2) on mitochondrial function and axonal regeneration of cultured DRG neurons and explore the pathways by which E2 acts. We observed that E2 treatment upregulated the levels of phosphorylated AMP-activated protein kinase (AMPK). E2 also increased the levels of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and activating transcription factor 3 (ATF3), which are proteins involved in mitochondrial biogenesis and axonal regeneration. The Seahorse assay showed that E2 elevated basal respiration in cultured DRG neurons. Additionally, E2 treatment for 24 h significantly increased total neurite outgrowth of DRG neurons. Pharmacological inhibition of AMPK using Compound C inhibited E2-mediated increases in ATF3 expression and neurite outgrowth. The Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) inhibitor STO-609 blocked E2-mediated AMPK activation. Furthermore, we assessed whether these effects were mediated by ERα or ERβ by using the ERα selective agonist propyl pyrazole triol (PPT) and ERβ selective agonist diarylpropionitrile (DPN). PPT upregulated phosphorylated AMPK levels and increased total neurite outgrowth, whereas DPN was ineffective. The results demonstrate that E2 acts through ERα to promote neurite outgrowth via a pathway involving activation of CaMKKβ/AMPK in adult DRG neurons. Our findings identify ERα-mediated AMPK activation as a therapeutic target for enhancing neuronal regeneration and mitochondrial function in neurodegenerative disorders.

Polysaccharide from Momordica charantia L. Alleviates Type 2 Diabetes Mellitus in Mice by Activating the IRS1/PI3K/Akt and AMPK Signaling Pathways and Regulating the Gut Microbiota

Developing effective therapies for type 2 diabetes mellitus (T2DM) remains a critical global health priority. This study explored the novel antidiabetic potential of MCPS-3, a polysaccharide derived from Momordica charantia L., and its underlying mechanisms in a high-fat diet and streptozotocin-induced T2DM mouse model. Our results indicated that MCPS-3 treatment significantly reduced serum glucose levels, improved glucose tolerance, and enhanced insulin sensitivity, alongside increased glycogen storage and improved liver enzyme activities. It also alleviated diabetes-induced damage in the pancreas, liver, and kidneys and improved serum lipid profiles by lowering triglycerides and LDL-C while increasing HDL-C levels. Mechanistic studies revealed that MCPS-3 activated the IRS1/PI3K/AKT and AMPK pathways, essential for glucose and lipid regulation. Importantly, MCPS-3 treatment restored gut microbial balance by increasing microbial diversity and shifting the composition of harmful and beneficial bacteria. Metabolomic analysis further identified changes in 46 metabolites, implicating pathways related to steroid and lipid metabolism. These findings underscore the multifaceted nature of MCPS-3's antidiabetic effects, including its role as a modulator of gut microbiota and metabolic pathways, and support its potential as a therapeutic agent for improving metabolic health in T2DM.

Action and therapeutic targets of folliculin interacting protein 1: a novel signaling mechanism in redox regulation

Rapid activation of adenosine monophosphate-activated protein kinase (AMPK) induces phosphorylation of mitochondrial-associated proteins, a process by which phosphate groups are added to regulate mitochondrial function, thereby modulating mitochondrial energy metabolism, triggering an acute metabolic response, and sustaining metabolic adaptation through transcriptional regulation. AMPK directly phosphorylates folliculin interacting protein 1 (FNIP1), leading to the nuclear translocation of transcription factor EB (TFEB) in response to mitochondrial functions. While mitochondrial function is tightly linked to finely-tuned energy-sensing mobility, FNIP1 plays critical roles in glucose transport and sensing, mitochondrial autophagy, cellular stress response, and muscle fiber contraction. Consequently, FNIP1 emerges as a promising novel target for addressing aberrant mitochondrial energy metabolism. Recent evidence indicates that FNIP1 is implicated in mitochondrial biology through various pathways, including AMPK, mTOR, and ubiquitination, which regulate mitochondrial autophagy, oxidative stress responses, and skeletal muscle contraction. Nonetheless, there is a dearth of literature discussing the physiological mechanism of action of FNIP1 as a novel therapeutic target. This review outlines how FNIP1 regulates metabolic-related signaling pathways and enzyme activities, such as modulating mitochondrial energy metabolism, catalytic activity of metabolic enzymes, and the homeostasis of metabolic products, thereby controlling cellular function and fate in different contexts. Our focus will be on elucidating how these metabolite-mediated signaling pathways regulate physiological processes and inflammatory diseases.

Therapeutic effects of stevia aqueous extract alone or in combination with metformin in induced polycystic ovary syndrome rats: Gene expression, hormonal balance, and metabolomics aspects

OBJECTIVES

This study aimed to assess the individual and combined effects of SAE and Met on the expression of genes related to insulin signaling, oxidative stress, hormonal imbalance, insulin resistance, and dyslipidemia in rats with induced PCOS.

METHODS

The estrous cycle of 50 adult Wistar female rats was monitored through vaginal smears. Subsequently, the rats were randomly assigned into five groups of 10, including control (receiving 1ml of carboxymethyl cellulose for 49 days), induction (letrozole at 1mg/kg/d for 21 days), SAE, Met, and SAE/Met. SAE and Met were orally administered at doses of 400mg/kg/d and 250mg/kg/d on day 22 and continued for an additional 28 days. Vaginal smears were analyzed, and gene expression levels of GLUT4, SIRT1, TNF-α, and INSR were evaluated using RT-qPCR. Antioxidant parameters were assessed using detection kits.

RESULTS

Treatment with SAE and Met restored a regular estrous cycle pattern in PCOS rats. Furthermore, SAE and Met treatment improved hormonal balance, dyslipidemia, and hyperglycemia in the rats. Administration of SAE and Met significantly elevated levels of antioxidant enzymes SOD and GPx in ovarian tissue (P<0.001). Additionally, mRNA levels of GLUT4, SIRT1, and INSR were significantly increased in ovarian tissue following SAE and Met treatment, while TNF-α gene expression decreased significantly (P<0.0001).

CONCLUSION

The findings suggest that SAE and Met aqueous extract exert protective effects on letrozole-induced PCOS in rats by modulating gene expression associated with insulin signaling and oxidative stress.

Glutamate increases the lean percentage and intramuscular fat content and alters gut microbiota in Shaziling pigs

This study aimed to explore the effects of glutamate (Glu) supplementation on the growth performance, carcass traits, meat quality, composition of amino acids and fatty acids in the longissimus dorsi muscle, and the colonic microbial community of Shaziling pigs. A total of 48 healthy male Shaziling pigs (150 d, 31.56 ± 0.95 kg) were randomly assigned to two groups, and fed a basal diet with no supplement (control group) or supplemented with 1% Glu (Glu group) for 51 d, and 6 pigs per group were finally slaughtered. Glu significantly increased the average daily gain (P = 0.039), lean percentage (P = 0.023), and intramuscular fat (IMF) content (P = 0.015), and decreased the fat percentage (P = 0.021) of Shaziling pigs. In the muscle, Glu increased the concentrations of inosine-5'-monophosphate (P = 0.094), Fe (P = 0.002), Cu (P = 0.052), and monounsaturated fatty acids (MUFAs) (P = 0.024), and decreased the content of C18:2n6 (P = 0.011), n-6 polyunsaturated fatty acids (n-6 PUFAs) (P = 0.014), and PUFAs (P = 0.014). Moreover, Glu significantly upregulated the mRNA expression of adipogenesis-related genes (FAS, SREBP-1C) (P = 0.032, P = 0.026) and muscle growth-related genes (MyHCⅡb, MyHCⅡx) (P = 0.038, P = 0.019) in the muscle, and increased the relative abundance of Spirochaetota (P < 0.001) and the acetic acid content in the colon (P = 0.039). Correlation analysis indicated that the acetic acid content was positively correlated with the relative Spirochaetota abundance and the IMF content, and a negative trend with the fat percentage of Shaziling pigs. In conclusion, these results indicated that Glu could simultaneously increase the lean percentage and IMF content and decrease the fat percentage of Shaziling pigs, and these beneficial effects may be related to increased colonic Spirochaetota abundance and acetic acid concentrations.

Ameliorative effects of Asiasarum root and rhizome extract on high fat diet‑induced obesity in mice through regulation of the SIRT1/PGC1α/AMPK pathways in muscle and liver tissues

Asiasarum root and rhizome (Asarum) is commonly used as a diaphoretic. Due to its warm and pungent characteristics in traditional Chinese and Korean medicine, it is considered as having the potential to prevent disease. The present study investigated the effects of Asarum extract on the symptoms of obesity in mice, and the regulation of energy metabolism in the liver and skeletal muscle tissues. In addition, to identify the potential molecular targets and signaling pathways involved in the mechanism of action of Asarum extract in obesity, network pharmacological and molecular docking analysis was performed. In vitro studies demonstrated that Asarum extract significantly increased the expression of regulators of energy metabolism [sirtuin 1 (SIRT1), peroxisome proliferator‑activated receptor γ coactivator 1‑α (PGC1α), nuclear respiratory factor 1, AMP‑activated protein kinase (AMPK) and glucose transporter type 4 (GLUT4)] and myogenic regulatory factors (MyoD, myogenin and myosin heavy chain) in C2C12 myotubes. Furthermore, the in vivo studies demonstrated that Asarum extract could reduce increases in body weight, and the levels of blood glucose, insulin, total cholesterol, triglycerides and low‑density lipoprotein cholesterol in the sera of obese mice. Asarum extract also improved pathological changes in the liver and pancreatic tissues of obese mice, and significantly increased the ratio of brown fat mass to body weight. In addition, Asarum extract reversed the expression of energy metabolism regulators and myogenic regulatory factors in the gastrocnemius tissues of obese mice. Asarum extract also activated the expression of SIRT1, PGC1α and AMPK in the liver tissues of obese mice. These findings indicated that Asarum extract may exert anti‑obesity effects, such as body weight loss, decreases in lipid metabolite levels, and inhibition of pancreatic and liver damage. Using network pharmacological analysis, the mechanisms underlying the effects of Asarum extract on the regulation of energy metabolism were explored, particularly in skeletal muscle and liver tissues.

The regulation of cell metabolism by hypoxia and hypercapnia

Every cell in the body is exposed to a certain level of CO2 and O2. Hypercapnia and hypoxia elicit stress signals to influence cellular metabolism and function. Both conditions exert profound yet distinct effects on metabolic pathways and mitochondrial dynamics, highlighting the need for cells to adapt to changes in the gaseous microenvironment. The interplay between hypercapnia and hypoxia signaling is the key for dictating cellular homeostasis as microenvironmental CO2 and O2 levels are inextricably linked. Hypercapnia, characterized by elevated pCO2, introduces metabolic adaptations within the aerobic metabolism pathways, affecting tricarboxylic acid cycle flux, lipid, and amino acid metabolism, oxidative phosphorylation and the electron transport chain. Hypoxia, defined by reduced oxygen availability, necessitates a shift from oxidative phosphorylation to anaerobic glycolysis to sustain ATP production, a process orchestrated by the stabilization of hypoxia-inducible factor-1α. Given that hypoxia and hypercapnia are present in both physiological and cancerous microenvironments, how might the coexistence of hypercapnia and hypoxia influence metabolic pathways and cellular function in physiological niches and the tumor microenvironment?

Suzi Daotan Decoction alleviates asthmatic airway remodeling through the AMPK/SIRT1/PGC-1α signaling pathway and PI3K/AKT signaling pathway

Suzi Daotan Decoction (SZDTD), recorded in the "New Edition of the Sasang of Eastern Medicine", serves as a prominent formula for managing asthma in Shao-Yin individuals in Korean traditional medicine. This prescription demonstrates clinical efficacy in asthma treatment and is associated with anti-inflammatory and antioxidant properties. Nonetheless, the precise underlying mechanism remains incompletely understood. This study aims to elucidate the impact of SZDTD in ameliorating asthmatic airway remodeling and investigate whether its mechanism is related to the AMPK/SIRT1/PGC-1α and PI3K/AKT signaling pathways. Through network pharmacology analysis, the components and putative targets of SZDTD were investigated, along with the target genes associated with allergic asthma. Enrichment analysis identified the AMPK/SIRT1/PGC-1α and PI3K/AKT signaling pathways as relevant pathways. Subsequently, in an allergic asthma mouse model sensitized and challenged with ovalbumin (OVA), mice were orally administered a low dose of SZDTD, a high dose of SZDTD, or dexamethasone before the challenge. The control group received 0.9% NaCl only. The number of inflammatory cells was assessed using Diff-Quik staining. The levels of interleukin-4(IL-4), IL-5, IL-13 in broncho-alveolar lavage fluid (BALF), total immunoglobulin E(IgE), and OVA-specific IgE in serum were detected by Enzyme-linked immunosorbent assay. IL-4 and interferon γ (IFN-γ) in spleen and lymph were detected by flow cytometry. Histological staining was employed to observe lung tissue pathology. Protein levels were evaluated using Immunohistochemistry(IHC), Western blotting (WB), and immunofluorescence (IF). Furthermore, BEAS-2B human bronchial epithelial cells stimulated with LPS were treated with varying concentrations of SZDTD, and WB analysis was conducted to determine associated protein levels. SZDTD demonstrated a significant reduction in inflammatory cell infiltration, as well as decreased levels of IL-4, IL-5, and IL-13 in BALF, and total IgE and ovalbumin-specific IgE levels in serum. Flow cytometry analysis revealed that SZDTD treatment led to decreased levels of IFN-γ and IL-4 in the lymph nodes and spleen, with a more pronounced effect observed on IL-4 level. Moreover, results from MASSON staining indicated that SZDTD treatment markedly reduced the expression of α-SMA (α-smooth muscle actin) and mitigated collagen deposition symptoms. Furthermore, SZDTD stimulated the phosphorylation of Adenosine 5'-monophosphate-activated protein kinase (AMPK) and enhanced the expression of Silent information regulator 1 (SIRT1) and Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), while inhibiting the expression of P-PI3K, P-AKT. In vitro experiments showed that SZDTD promoted the phosphorylation of AMPK, increased the expression of SIRT1 and PGC-1α, and suppressed the expression of P-PI3K, P-AKT. SZDTD can alleviate airway remodeling in allergic asthma by a mechanism related to activation of AMPK/SIRT1/PGC-1α and inhibition of PI3K/AKT signaling pathways.

Effect of time-restricted feeding and caloric restriction in metabolic associated fatty liver disease in male rats

BACKGROUND

The prevalence of metabolic associated fatty liver disease (MAFLD) is high. However, there are few studies on the effects of time-restricted feeding (TRF) and caloric restriction (CR) in MAFLD.

OBJECTIVES

To investigate the efficacy and mechanism of 4 h TRF and 60% CR in MAFLD.

METHODS

Twelve male Sprague-Dawley rats were randomly assigned to the Normal group (normal diet, 10 kcal% fat), while the remaining 38 rats were assigned to the MAFLD group (high-fat diet, 60 kcal% fat). 10 weeks later, the MAFLD group was randomly divided into the 4 h TRF, 60% CR, 4 h TRF + 60% CR, and Model groups; all rats were then given normal diet. After 4 weeks, weight, blood lipid, and other indicators were detected.

RESULTS

After the high-fat diet was discontinued, the liver lipid levels in the rat with MAFLD significantly reduced, while the body weight was not significantly changed. The rats in the Model group were heavier than those in the other four groups (p < 0.01). The triglyceride levels were higher in the TRF + CR group compared with the Model group (p < 0.01). Compared with the Model group, 110 metabolites were decreased in the TRF + CR group, and 83 metabolites were elevated in liver. Kyoto Encyclopedia of Genes and Genomes revealed that the mechanism involved the proliferator-activated receptor alpha signaling pathway, metabolic pathway, and so on. We observed differences in silent information regulator transcript 1 (SIRT1) mRNA levels in all five groups (p = 0.003).

CONCLUSIONS

4 h TRF and 60% CR significantly reduced body weight and liver lipid in rats with MAFLD. 4 h TRF can improve MAFLD, and there is no need to excessively restrict food intake.

High intensity interval training alters gene expression linked to mitochondrial biogenesis and dynamics in high fat diet fed rats

A High-Fat Diet (HFD) leads to disruption of mitochondrial biogenesis and dynamics. Exercise training, especially High-Intensity Interval Training (HIIT) increases mitochondrial biogenesis and dynamics. The present study aimed to investigate the effect of a period of HIIT with and without HFD consumption on the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc1-α), Mitofusins-2 (Mfn2), Optic atrophy-1 (Opa1), Dynamin-related protein-1 (Drp1) and mitochondrial Fission protein-1 (Fis1) genes as indicators of mitochondrial biogenesis and dynamics function in the soleus muscle of male Wistar rats. Twenty-four healthy male Wistar rats were randomly divided into four groups: (1) Control, (2) Control + HIIT, (3) HFD, and (4) HFD + HIIT. The HIIT training protocol lasted for 10 weeks with a frequency of 3 sessions per week. The Real-Time Quantitative Reverse Transcription PCR method was used to investigate the gene expression. One-way ANOVA and Fisher's post-hoc analyses were used to examine group differences. HFD consumption caused an increase in weight (P < 0.05), the expression of Drp1 and Fis1 genes (P < 0.001), and a decreased expression of Pgc1-α, Mfn2, and Opa1 genes (P < 0.001). HIIT training increased the expression of PGC1-α (P = 0.009), Mfn2 (P < 0.004), and Opa1 (P < 0.011) genes, while it decreased the expression of Drp1 (P = 0.003) and Fis1 genes (P = 0.027). These findings suggest that HIIT can counteract the negative effects of HFD on mitochondrial function by modulating gene expression related to mitochondrial biogenesis and dynamics.

Plant-Derived Treatments for Different Types of Muscle Atrophy

With the development of medicine and chemistry, an increasing number of plant-derived medicines have been shown to exert beneficial therapeutic on the treatment of various physical and psychological diseases. In particular, by using physical chemistry methods, we are able to examine the chemical components of plants and the effects of these substances on the human body. Muscle atrophy (MA) is characterized by decreased muscle mass and function, is caused by multiple factors and severely affects the quality of life of patients. The multifactorial and complex pathogenesis of MA hinders drug research and disease treatment. However, phytotherapy has achieved significant results in the treatment of MA. We searched PubMed and the Web of Science for articles related to plant-derived substances and muscle atrophy. After applying exclusion and inclusion criteria, 166 and 79 articles met the inclusion criteria, respectively. A total of 173 articles were included in the study after excluding duplicates. The important role of phytoactives such as curcumin, resveratrol, and ginsenosides in the treatment of MA (e.g., maintaining a positive nitrogen balance in muscles and exerting anti-inflammatory and antioxidant effects) has been extensively studied. Unfortunately, MA dose not have to a single cause, and each cause has its own unique mechanism of injury. This review focuses on the therapeutic mechanisms of active plant components in MA and provides insights into the personalized treatment of MA.

Sirtuin1 in Spinal Cord Injury: Regulatory Mechanisms, Microenvironment Remodeling and Therapeutic Potential

BACKGROUND

Spinal cord injury (SCI) is a complex central nervous system disorder characterized by multifaceted pathological processes, including inflammation, oxidative stress, programmed cell death, autophagy, and mitochondrial dysfunction. Sirtuin 1 (Sirt1), a critical NAD+-dependent deacetylase, has emerged as a promising therapeutic target for SCI repair due to its potential to protect neurons, regulate glial and vascular cells, and optimize the injury microenvironment. However, the regulatory roles of Sirt1 in SCI are complex and challenging, as its effects vary depending on activation timing, expression levels, and cell types.

METHODS

A systematic literature review was conducted using PubMed, Scopus, and Web of Science to identify studies investigating Sirt1 in SCI. Relevant publications were analyzed to synthesize current evidence on Sirt1's mechanisms, therapeutic effects, and challenges in SCI repair.

RESULTS

Sirt1 exerts broad regulatory effects across diverse pathological processes and cell types post-SCI. It promotes neuronal survival and axonal regeneration, modulates astrocytes and microglia to resolve inflammation, supports oligodendrocyte-mediated myelination, and enhances vascular endothelial function. Proper Sirt1 activation may mitigate secondary injury, whereas excessive or prolonged activation could impair inflammatory resolution or disrupt cellular homeostasis. This review highlights Sirt1 activation as potential therapies, but challenges include optimizing spatiotemporal activation and addressing dual roles in different cell types.

CONCLUSION

Targeting Sirt1 represents a viable strategy for SCI repair, given its multifaceted regulation of neuroprotection, immunomodulation, and tissue remodeling. However, translating these findings into therapies requires resolving critical issues such as cell type-specific delivery, precise activation timing, and dosage control. This review provides a theoretical foundation and practical insights for advancing Sirt1-based treatments for SCI.

The link between Mitochondria and Sarcopenia

Sarcopenia, a widespread condition, is characterized by a variety of factors influencing its development. The causes of sarcopenia differ depending on the age of the individual. It is defined as the combination of decreased muscle mass and impaired muscle function, primarily observed in association with ageing. As people age from 20 to 80 years old, there is an approximate 30% reduction in muscle mass and a 20% decline in cross-sectional area. This decline is attributed to a decrease in the size and number of muscle fibres. The regression of muscle mass and strength increases the risk of fractures, frailty, reduced quality of life, and loss of independence. Muscle cells, fibres, and tissues shrink, resulting in diminished muscle power, volume, and strength in major muscle groups. One prominent theory of cellular ageing posits a strong positive relationship between age and oxidative damage. Heightened oxidative stress leads to early-onset sarcopenia, characterized by neuromuscular innervation breakdown, muscle atrophy, and dysfunctional mitochondrial muscles. Ageing muscles generate more reactive oxygen species (ROS), and experience decreased oxygen consumption and ATP synthesis compared to younger muscles. Additionally, changes in mitochondrial protein interactions, cristae structure, and networks may contribute to ADP insensitivity, which ultimately leads to sarcopenia. Within this framework, this review provides a comprehensive summary of our current understanding of the role of mitochondria in sarcopenia and other muscle degenerative diseases, highlighting the crucial need for further research in these areas.

Muscarinic acetylcholine type 1 receptor antagonism activates TRPM3 to augment mitochondrial function and drive axonal repair in adult sensory neurons

OBJECTIVE

Antagonism of the muscarinic acetylcholine type 1 receptor (M1R) promotes sensory axon repair and is protective in peripheral neuropathy, however, the mechanism remains elusive. We investigated the role of the heat-sensing transient receptor potential melastatin-3 (TRPM3) cation channel in M1R antagonism-mediated nerve regeneration and explored the potential of TRPM3 activation to facilitate axonal plasticity.

METHODS

Dorsal root ganglion (DRG) neurons from adult control or diabetic rats were cultured and treated with TRPM3 agonists (CIM0216, pregnenolone sulfate) and M1R antagonists pirenzepine (PZ) or muscarinic toxin 7 (MT7). Ca2+ transients, mitochondrial respiration, AMP-activated protein kinase (AMPK) expression, and mitochondrial inner membrane potential were analyzed. The effect of M1R activation or blockade on TRPM3 activity mediated by phosphatidylinositol 4,5-bisphosphate (PIP2) was studied. Metabolic profiling of DRG neurons and human neuroblastoma SH-SY5Y cells was conducted.

RESULTS

M1R antagonism induced by PZ or MT7 increased Ca2+ influx in DRG neurons and was inhibited by TRPM3 antagonists or in the absence of extracellular Ca2+. TRPM3 agonists elevated Ca2+ levels, augmented mitochondrial respiration, AMPK activation and neurite outgrowth. M1R antagonism stimulated TRPM3 channel activity through inhibition of PIP2 hydrolysis to activate Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ)/AMPK, leading to augmented mitochondrial function and neuronal metabolism. DRG neurons with AAV-mediated shRNA knockdown of TRPM3 exhibited suppressed antimuscarinic drug-induced neurite outgrowth. TRPM3 agonists increased glycolysis and TCA cycle metabolites, indicating enhanced metabolism in DRG neurons and SH-SY5Y cells.

CONCLUSIONS

Activation of the TRPM3/CaMKKβ/AMPK pathway promoted collateral sprouting of sensory axons, positioning TRPM3 as a promising therapeutic target for peripheral neuropathy.

MDPAO1 peptide from human milk enhances brown adipose tissue thermogenesis and mitigates obesity

The regulatory effect of breastfeeding on offspring metabolism has garnered significant attention as an effective strategy in combating childhood obesity. However, the underlying mechanism remains largely unknown. Through integrated analysis of multiple human milk peptide databases and functional screening, MDPAO1 (milk-derived peptide associated with obesity 1) was identified as having potential activity in promoting the expression of thermogenic genes. In lactating mice, intervention with MDPAO1 enhanced the thermogenic phenotype of brown adipose tissue (BAT) and overall metabolic activity. Moreover, MDPAO1 intervention led to reduced body weight gain, increased brown fat mass, and improved glucose tolerance and insulin sensitivity in a mouse model of high-fat diet (HFD)-induced obesity. RNA-seq analysis of BAT post-MDPAO1 intervention revealed close association with mitochondrial oxidative respiratory chain and mitophagy. Subsequent in vitro experiments conducted on primary brown adipocytes confirmed that MDPAO1 inhibited mitophagy, increased mitochondrial mass, and elevated levels of mitochondrial respiratory chain complexes. In conclusion, this study underscores the potential of MDPAO1, a peptide enriched in breast milk, in activating the thermogenic phenotype of brown adipose tissue and mitigating obesity, thus offering novel insights into the mechanisms underlying breastfeeding's role in preventing childhood obesity.

Cannabidiol reshapes the gut microbiome to promote endurance exercise in mice

Cannabidiol (CBD), a nonpsychoactive compound from Cannabis, has various bioactive functions in humans and animals. Evidence suggests that CBD promotes muscle injury recovery in athletes, but whether and how CBD improves endurance performance remains unclear. Here we investigated the effects of CBD treatment on exercise performance in mice and assessed whether this effect involves the gut microbiome. CBD administration significantly increased treadmill running performance in mice, accompanied by an increase in oxidative myofiber composition. CBD also increased mitochondrial biogenesis and the expression of associated genes such as PGC-1α, phosphorylated CREB and AMPK in muscle tissue. Interestingly, CBD altered the composition of the gut microbiome, and antibiotic treatment reduced the muscle endurance-enhancing effects of CBD and mitochondrial biogenesis. We isolated Bifidobacterium animalis, a microbe increased by CBD administration, and named it KBP-1. Treatment with B. animalis KBP-1 in mice resulted in improved running performance. Whole-genome analysis revealed that B. animalis KBP-1 presented high expression of genes involved in branched-chain amino acid biosynthesis, expression of branched-chain amino acid release pumps and metabolism of lactic acid. In summary, our study identified CBD and B. animalis KBP-1 as potential endurance exercise-promoting agents.

Role of PGC-1α in the proliferation and metastasis of malignant tumors

Malignant tumors are among the major diseases threatening human survival in the world, and advancements in medical technology have led to a steady increase in their detection rates worldwide. Despite unique clinical presentations across the spectrum of malignancies, treatment modalities generally adhere to common strategies, encompassing primarily surgical intervention, radiation therapy, chemotherapy, and targeted treatments. Uncovering the genetic elements contributing to cancer cell proliferation, metastasis, and drug resistance remains a pivotal pursuit in the development of novel targeted therapeutics. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A/PGC-1α) is a transcriptional coactivator that influences most cellular metabolic pathways. Its aberrant expression is associated with numerous chronic diseases, including diabetes, heart failure, neurodegenerative disorders, and cancer development. This study primarily discusses the structure, physiological functions, regulatory mechanisms, and research advancement concerning the role of PGC-1α in the proliferation and metastasis of malignant tumors. Targeting PGC-1α and its related regulatory pathways for therapeutic interventions holds promise in facilitating precise and individualized oncological treatments. This approach is expected to counteract drug resistance in patients with cancer and offer a novel direction for the treatment of malignant tumors.

Study on the role of Dihuang Yinzi in regulating the AMPK/SIRT1/PGC-1α pathway to promote mitochondrial biogenesis and improve Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Dihuang Yinzi (DHYZ) is a classic prescription in traditional Chinese medicine. Its therapeutic effect on Alzheimer's disease (AD) has been widely validated. However, the underlying molecular mechanisms of DHYZ in AD treatment remain unclear and require further research.

AIM OF THE STUDY

Elucidating DHYZ's promotion of mitochondrial biogenesis through the AMPK/SIRT1/PGC-1α pathway improves neuronal loss, mitochondrial damage, and memory deficits in AD.

MATERIALS AND METHODS

Administering DHYZ by gavage to SAMP8 mice, after completing behavioral tests, the effects of DHYZ on hippocampal neuron loss and mitochondrial structural damage in AD model mice were assessed using Nissl staining and transmission electron microscopy. Western blot was used to detect the expression of mitochondrial biogenesis-related proteins PGC-1α, CREB, mitochondrial fusion protein MFN2, and mitochondrial fission proteins DRP1 and FIS1. At the same time, immunofluorescence (IF) was employed to measure the relative fluorescence intensity of mitochondrial fusion protein MFN1. After determining the optimal dose of DYHZ for treating AD, we conducted mechanistic studies. By intraperitoneally injecting SAMP8 mice with the AMPK inhibitor (Compound C) to inhibit AMPK protein expression and subsequently treating them with DHYZ, the impact of DHYZ on hippocampal neurons in AD model mice was evaluated using Nissl and hematoxylin-eosin staining. Western blot was used to detect the protein expression of AMPK, p-AMPK, SIRT1, PGC-1α, NRF1, and TFAM. In contrast, IF was used to measure the relative fluorescence intensity of PGC-1α, NRF1, and TFAM proteins in the hippocampal CA1 region.

RESULTS

DHYZ significantly improved AD model mice's cognitive impairment and memory deficits and mitigated hippocampal neuron loss and degeneration. Additionally, it ameliorated mitochondrial morphological structures. DHYZ upregulated the protein expression of mitochondrial biogenesis-related proteins PGC-1α, CREB, and mitochondrial fusion proteins MFN1 and MFN2 while inhibiting the expression of mitochondrial fission proteins DRP1 and FIS1. Further studies revealed that DHYZ could upregulate the expression of the AMPK/SIRT1/PGC-1α pathway proteins and their downstream proteins NRF1 and TFAM.

CONCLUSION

DHYZ promotes mitochondrial biogenesis by activating the AMPK/SIRT1/PGC-1α signaling pathway, thereby improving memory deficits, neuronal loss, and mitochondrial dysfunction in AD.

Fatty Acid Esterification of Octacosanol Attenuates Triglyceride and Cholesterol Synthesis in Mice

This study aimed to evaluate the cholesterol-regulatory effects of lauric-acid-esterified octacosanol (LEO) and oleic-acid-esterified octacosanol (OEO) compared to their unmodified counterparts and to investigate the underlying mechanisms by partially substituting the fat content in obese C57BL/6J mice induced with a high-fat diet (HFD). Rice bran oil and coconut oil were also investigated as they are rich in oleic acid and lauric acid, respectively. The results showed that all supplemented groups significantly inhibited weight gain induced by the HFD, but the groups treated with esterified octacosanol exhibited a more pronounced effect. Esterified octacosanol inhibited fatty acid synthesis via the Sirtuin 1/AMP-activated protein kinase/Sterol regulatory element-binding protein 1 (SIRT1/AMPK/SREBP-1c) pathway by decreasing fatty acid synthase (FASN) (0.78 fold ±0.09, p < 0.05) transcription and affecting the phospho-acetyl-coA carboxylase/acetyl-coA carboxylase (p-ACC/ACC) (1.42 fold ±0.18, p < 0.05) ratio, as well as by inhibiting cholesterol synthesis by reducing sterol regulatory element-binding protein 2 (SREBP-2) (0.75 fold ±0.08, p < 0.05) and low-density lipoprotein receptor (LDL-R) (1.24 fold ±0.1, p < 0.05), which are responsible for cholesterol uptake. Our findings indicate that OEO had a greater influence on fatty acid and cholesterol synthesis compared to the other agents.

Single-Cell RNA sequencing reveals mitochondrial dysfunction in microtia chondrocytes

Microtia is a congenital malformation characterized by underdevelopment of the external ear. While chondrocyte dysfunction has been implicated in microtia, the specific cellular abnormalities remain poorly understood. This study aimed to investigate mitochondrial dysfunction in microtia chondrocytes using single-cell RNA sequencing. Cartilage samples were obtained from patients with unilateral, non-syndromic microtia and healthy controls. Single-cell RNA sequencing was performed using the 10 × Genomics platform. Bioinformatic analyses including cell type identification, trajectory analysis, and gene co-expression network analysis were conducted. Mitochondrial function was assessed through ROS levels, membrane potential, and transmission electron microscopy. Chondrocytes from microtia samples showed lower mitochondrial function scores compared to normal samples. Trajectory analysis revealed more disorganized differentiation patterns in microtia chondrocytes. Mitochondrial dysfunction in microtia chondrocytes was confirmed by increased ROS production, decreased membrane potential, and altered mitochondrial structure. Gene co-expression network analysis identified hub genes associated with mitochondrial function, including SDHA, SIRT1, and PGC1A, which showed reduced expression in microtia chondrocytes. This study provides evidence of mitochondrial dysfunction in microtia chondrocytes and identifies potential key genes involved in this process. These findings offer new insights into the pathogenesis of microtia and may guide future therapeutic strategies.

Emerging targets in amyotrophic lateral sclerosis (ALS): The promise of ATP-binding cassette (ABC) transporter modulation

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative primarily affecting motor neurons, leading to disability and neuronal death, and ATP-Binding Cassette (ABC) transporter due to their role in drug efflux and modulation of various cellular pathways contributes to the pathogenesis of ALS. In this article, we extensively investigated various molecular and mechanistic pathways linking ALS transporter to the pathogenesis of ALS; this involves inflammatory pathways such as Mitogen-Activated Protein Kinase (MAPK), Phosphatidylinositol-3-Kinase/Protein Kinase B (PI3K/Akt), Toll-Like Receptor (TLR), Glycogen Synthase Kinase 3β (GSK-3β), Nuclear Factor Kappa-B (NF-κB), and Cyclooxygenase (COX). Oxidative pathways such as Astrocytes, Glutamate, Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Sirtuin 1 (SIRT-1), Forkhead box protein O (FOXO), Extracellular signal-regulated kinase (ERK). Additionally, we delve into the role of autophagic pathways like TAR DNA-binding protein 43 (TDP-43), AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and lastly, the apoptotic pathways. Furthermore, by understanding these intricate interactions, we aim to develop novel therapeutic strategies targeting ABC transporters, improving drug delivery, and ultimately offering a promising avenue for treating ALS.

Mitochondrial quality control: a pathophysiological mechanism and potential therapeutic target for chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a prevalent chronic respiratory disease worldwide. Mitochondrial quality control mechanisms encompass processes such as mitochondrial biogenesis, fusion, fission, and autophagy, which collectively maintain the quantity, morphology, and function of mitochondria, ensuring cellular energy supply and the progression of normal physiological activities. However, in COPD, due to the persistent stimulation of harmful factors such as smoking and air pollution, mitochondrial quality control mechanisms often become deregulated, leading to mitochondrial dysfunction. Mitochondrial dysfunction plays a pivotal role in the pathogenesis of COPD, contributing toinflammatory response, oxidative stress, cellular senescence. However, therapeutic strategies targeting mitochondria remain underexplored. This review highlights recent advances in mitochondrial dysfunction in COPD, focusing on the role of mitochondrial quality control mechanisms and their dysregulation in disease progression. We emphasize the significance of mitochondria in the pathophysiological processes of COPD and explore potential strategies to regulate mitochondrial quality and improve mitochondrial function through mitochondrial interventions, aiming to treat COPD effectively. Additionally, we analyze the limitations and challenges of existing therapeutic strategies, aiming to provide new insights and methods for COPD treatment.

Microglial activation states and their implications for Alzheimer's Disease

Alzheimer's Disease (AD) is a chronic neurodegenerative disorder characterized by the accumulation of toxic amyloid-beta (Aβ) plaques and neurofibrillary tangles (NFTs) of tau protein in the brain. Microglia, key immune cells of the central nervous system, play an important role in AD development and progression, primarily through their responses to Aβ and NFTs. Initially, microglia can clear Aβ, but in AD, chronic activation overwhelms protective mechanisms, leading to sustained neuroinflammation that enhances plaque toxicity, setting off a damaging cycle that affects neurons, astrocytes, cerebral vasculature, and other microglia. Current AD treatments have been largely ineffective, though emerging immunotherapies focusing on plaque removal show promise, but often overlook the role of neuroinflammation. Activated microglia display a complex range of phenotypes that can be broadly broken into pro- or anti-inflammatory states, although this dichotomy does not describe the significant overlap between states. Aβ can strongly induce inflammatory activity, triggering the production of reactive oxygen species, inflammatory cytokines (e.g., TNF-α, IL-1β, IL-6), synapse engulfment, blood-brain barrier compromise, and impaired Aβ clearance. These processes contribute to neural tissue loss, manifesting as cognitive decline such as impaired executive function and memory. Conversely, anti-inflammatory activation exerts neuroprotective effects by suppressing inflammatory pathways and releasing neurotrophic factors that aid neuron repair and protection. Induction of anti-inflammatory states may offer a dual therapeutic approach to address both neuroinflammation and plaque accumulation in AD. This approach suggests potential strategies to modulate microglial phenotypes, aiming to restore neuroprotective functions and mitigate disease progression by simultaneously targeting inflammation and plaque pathology.

Mechanistic Insights on Cardioprotective Properties of Ursolic Acid: Regulation of Mitochondrial and Non-mitochondrial Pathways

Ursolic acid, a natural pentacyclic triterpenoid compound, has been shown to have significant cardioprotective effects in various preclinical studies. This article reviews the various mechanisms by which ursolic acid achieves its cardioprotective effects, highlighting its potent anti-oxidant, anti-inflammatory, and anti- apoptotic properties. Ursolic acid upregulates anti-oxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx), effectively reducing oxidative stress, thereby decreasing reactive oxygen species (ROS) and improving lipid peroxidation levels. Furthermore, ursolic acid downregulates pro-inflammatory cytokines and inhibits key inflammatory pathways, such as nuclear factor kappa B (NF-κB), which results in its anti-inflammatory effects. These actions help in protecting cardiac tissues from acute and chronic inflammation. Ursolic acid also promotes mitochondrial function and energy metabolism by enhancing mitochondrial biogenesis and reducing dysfunction, which is critical during ischemia-reperfusion (I/R) injury. Additionally, ursolic acid influences multiple molecular pathways, including B-cell leukemia/lymphoma 2 protein (Bcl- 2)/Bcl-2 associated x-protein (Bax), miR-21/extracellular signal-regulated kinase (ERK), and phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), to reduce cardiomyocyte apoptosis. Collectively, these properties make ursolic acid a promising therapeutic agent for cardiovascular diseases (CVDs), warranting further research and clinical trials to harness its potential fully.

GLP-1 Receptor Agonists Alleviate Diabetic Kidney Injury via β-Klotho-Mediated Ferroptosis Inhibition

Semaglutide (Smg), a GLP-1 receptor agonist (GLP-1RA), shows renal protective effects in patients with diabetic kidney disease (DKD). However, the exact underlying mechanism remains elusive. This study employs transcriptome sequencing and identifies β-Klotho (KLB) as the critical target responsible for the role of Smg in kidney protection. Smg treatment alleviates diabetic kidney injury by inhibiting ferroptosis in patients, animal models, and HK-2 cells. Notably, Smg treatment significantly increases the mRNA expression of KLB through the activation of the cyclic adenosine monophosphate (cAMP) signaling pathway, specifically through the phosphorylation of protein kinase A (PKA) and cAMP-response element-binding protein (CREB). Subsequently, the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway is activated, reprograming the key metabolic processes of ferroptosis such as iron metabolism, fatty acid synthesis, and the antioxidant response against lipid peroxidation. Suppression of ferroptosis by Smg further attenuates renal inflammation and fibrosis. This work highlights the potential of GLP-1RAs and KLB targeting as promising therapeutic approaches for DKD management.

Effects of Capsicum Oleoresin on the Energy Expenditure and Mitochondrial Content of Brown Adipose Tissue in Mice Fed a High-Fat Diet

Capsicum oleoresin (CO) is a concentrated extract derived from peppers (Capsicum annum L.) containing capsaicin (the active compound responsible for its pungency) and other bioactive components. The present study aimed to determine whether CO affects the energy expenditure and mitochondrial content of brown adipose tissue (BAT) in diet-induced obese mice. Four-week-old C57BL/6J mice were divided into three groups and fed with a normal chow diet, 45% high-fat diet (HF), or HF supplemented with 0.01% CO (HF+CO) for 16 weeks. The results showed that CO supplementation significantly suppressed weight gain and improved serum lipid profiles compared with HF feeding. The energy expenditure was significantly higher in the HF+CO group than in the HF group. Compared with the HF group, the HF+CO group had significantly upregulated the messenger RNA expression levels of uncoupling protein 1 (UCP1) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) in BAT. The mitochondrial DNA content, which was reduced by HF intake, was significantly restored in the HF+CO group. Furthermore, the mitochondrial size and number were restored in the HF+CO group than in in the HF group. The activity of adenosine monophosphate-activated protein kinase (AMPK) in BAT was significantly increased in the HF+CO group than in the HF group. In conclusion, CO potentially inhibits weight gain by increasing energy expenditure in diet-induced obese mice. This beneficial effect is likely associated with the enhancement of mitochondrial content by upregulating key markers, including UCP1, PGC-1α, and AMPK, in BAT.

Cinnamon for Metabolic Diseases and Their Cardiovascular and Hepatic Complications: A Mechanistic Review

Cinnamon is one of the world's oldest and most popular spices, and is derived from the inner bark of several tree species from the genus Cinnamomum. During the last two decades, cinnamon has demonstrated beneficial metabolic effects not only in animal experiments but also in clinical trials. Even recent meta-analyses have shown the protective effects of cinnamon on different components of metabolic syndrome and their complications. In the last 5 years, several experimental studies have unraveled the intricate molecular mechanisms underlying the antihypertensive, antihyperglycemic, lipid-lowering, weight-lowering, and cardioprotective properties of cinnamon. This review paper will discuss how cinnamon and its active components, particularly cinnamaldehyde, suppress inflammation and oxidative stress, modulate mitochondrial dysfunction, and regulate glucose uptake, insulin resistance, lipogenesis, beta-oxidation, Ca2+ signaling, and other cellar events at the molecular level. Specifically, we will delve into the molecular mechanisms involved in the metabolic effects of cinnamon to provide a deeper insight into how cinnamon can bring such beneficial effects. This review hopes to encourage the use of cinnamon in clinical settings, guide the combination of cinnamon with other drugs used to treat different components of metabolic syndrome based on their mechanism of action, and support the concept of complementary medicine for metabolic diseases.

Molecular pathways involved in the control of contractile and metabolic properties of skeletal muscle fibers as potential therapeutic targets for Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is caused by mutations in the gene encoding dystrophin, a subsarcolemmal protein whose absence results in increased susceptibility of the muscle fiber membrane to contraction-induced injury. This results in increased calcium influx, oxidative stress, and mitochondrial dysfunction, leading to chronic inflammation, myofiber degeneration, and reduced muscle regenerative capacity. Fast glycolytic muscle fibers have been shown to be more vulnerable to mechanical stress than slow oxidative fibers in both DMD patients and DMD mouse models. Therefore, remodeling skeletal muscle toward a slower, more oxidative phenotype may represent a relevant therapeutic approach to protect dystrophic muscles from deterioration and improve the effectiveness of gene and cell-based therapies. The resistance of slow, oxidative myofibers to DMD pathology is attributed, in part, to their higher expression of Utrophin; there are, however, other characteristics of slow, oxidative fibers that might contribute to their enhanced resistance to injury, including reduced contractile speed, resistance to fatigue, increased capillary density, higher mitochondrial activity, decreased cellular energy requirements. This review focuses on signaling pathways and regulatory factors whose genetic or pharmacologic modulation has been shown to ameliorate the dystrophic pathology in preclinical models of DMD while promoting skeletal muscle fiber transition towards a slower more oxidative phenotype.

Caffeic acid phenethyl ester restores mitochondrial homeostasis against peritoneal fibrosis induced by peritoneal dialysis through the AMPK/SIRT1 pathway

Increasing evidence suggests that peritoneal fibrosis induced by peritoneal dialysis (PD) is linked to oxidative stress. However, there are currently no effective interventions for peritoneal fibrosis. In the present study, we explored whether adding caffeic acid phenethyl ester (CAPE) to peritoneal dialysis fluid (PDF) improved peritoneal fibrosis caused by PD and explored the molecular mechanism. We established a peritoneal fibrosis model in Sprague-Dawley rats through intraperitoneal injection of PDF and lipopolysaccharide (LPS). Rats in the PD group showed increased peritoneal thickness, submesothelial collagen deposition, and the expression of TGFβ1 and α-SMA. Adding CAPE to PDF significantly inhibited PD-induced submesothelial thickening, reduced TGFβ1 and α-SMA expression, alleviated peritoneal fibrosis, and improved the peritoneal ultrafiltration function. In vitro, peritoneal mesothelial cells (PMCs) treated with PDF showed inhibition of the AMPK/SIRT1 pathway, mitochondrial membrane potential depolarization, overproduction of mitochondrial reactive oxygen species (ROS), decreased ATP synthesis, and induction of mesothelial-mesenchymal transition (MMT). CAPE activated the AMPK/SIRT1 pathway, thereby inhibiting mitochondrial membrane potential depolarization, reducing mitochondrial ROS generation, and maintaining ATP synthesis. However, the beneficial effects of CAPE were counteracted by an AMPK inhibitor and siSIRT1. Our results suggest that CAPE maintains mitochondrial homeostasis by upregulating the AMPK/SIRT1 pathway, which alleviates oxidative stress and MMT, thereby mitigating the damage to the peritoneal structure and function caused by PD. These findings suggest that adding CAPE to PDF may prevent and treat peritoneal fibrosis.

CTRP6-mediated cardiac protection in heart failure via the AMPK/SIRT1/PGC-1α signalling pathway

Heart failure (HF) remains a significant global health concern with limited effective treatments available. C1q/TNF-related protein 6 (CTRP6) is a member of the CTRP family analogous to adiponectin and its role in HF pathogenesis remains unclear. Here, we investigated the impact of CTRP6 on HF progression. To mimic heart failure with reduced ejection fraction (HFrEF), we used isoproterenol injection in mice and administered adenovirus vectors expressing CTRP6 (Ad-CTRP6) via tail vein injection. We assessed cardiac function through echocardiography and histology. CTRP6's effects on hypertrophy, fibrosis, apoptosis, oxidative stress and mitochondrial function were analysed. Downstream pathways (phosphorylated AMP-activated protein kinase (p-AMPK), sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) were studied in heart tissues. In vitro, isoproterenol-stimulated H9c2 cardiomyocytes were treated with CTRP6 to examine viability, apoptosis, F-actin and signalling proteins. Compound C was used to assess AMPK involvement. CTRP6 expression was lower in the plasma of HF patients. In an isoproterenol-induced HFrEF mouse model, adenovirus-mediated overexpression of CTRP6 ameliorated cardiac dysfunction and reduced cardiomyocyte apoptosis, oxidative stress, inflammation and myocardial injury markers. Mechanistically, CTRP6 activation of the AMPK/SIRT1/PGC-1α signalling pathway restored mitochondrial homeostasis, evidenced by reduced mitochondrial reactive oxygen species levels, increased ATP content, and enhanced mitochondrial complex I/III activities in cardiac tissues. In vitro studies using isoproterenol-stimulated H9c2 cardiomyocytes corroborated these findings, demonstrating that CTRP6 upregulation attenuated hypertrophy, apoptosis, oxidative stress and mitochondrial dysfunction. Furthermore, these effects were partially reversed by the AMPK inhibitor Compound C, implicating the involvement of the AMPK pathway in CTRP6-mediated cardioprotection. CTRP6 alleviates HF progression through the AMPK/SIRT1/PGC-1α signalling pathway.

Effects of feeding patterns on production performance, lipo-nutritional quality and gut microbiota of Sunit sheep

This study aimed to investigate the impact of feeding patterns on the production performance, lipo-nutritional quality, and gut microbiota of Sunit sheep. A total of 24 sheep were assigned to two groups: confinement feeding (CF) and pasture feeding (PF) groups. After 90 days, the CF group exhibited significantly increased average daily gain, carcass weight, backfat thickness, and intramuscular fat content of the sheep, whereas the PF group showed significantly increased pH24h and decreased L∗ value and cooking loss of the longissimus lumborum (LL) muscle (P < 0.05). In the PF group, the contents of linoleic, α-linolenic, and docosahexaenoic acids were considerably higher and the n-6/n-3 polyunsaturated fatty acid ratio was significantly lower (P < 0.05). Furthermore, the triglyceride, cholesterol, and nonesterified fatty acid levels in the serum of the CF group significantly increased, whereas the enzyme contents of fatty acid synthase (FASN) and hormone-sensitive lipase (HSL) in the LL muscle of the PF group were markedly elevated (P < 0.05). The PF group also showed altered expression of lipid metabolism-related genes, including upregulated FASN, HSL, fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) (P < 0.05). Meanwhile, differences were observed in the abundance of key bacteria and microbiota functions between the groups. Correlation analysis revealed that production performance and lipid metabolism may be related to the differential effects of bacteria. In conclusion, the transition in the feeding patterns of Sunit sheep caused changes in the gut microbial community and lipid metabolism level in the muscle as well as differences in fat deposition and meat quality.