The effect of celastrol on learning and memory in diabetic rats after sevoflurane inhalation

Effect of general anesthesia drugs on GFAP/Iba-1 expression: a meta-analysis

Glial fibrillary acidic protein (GFAP) is a marker associated with astrocyte activation and plays a role in various pathologic processes, including traumatic brain injury, stroke, and neurodegenerative diseases. Interacting boson approximation (Iba-1) is a marker protein for microglia, which are important in neuroinflammatory responses. This meta-analysis aimed to investigate the impact of general anesthetics on the expression of GFAP and Iba-1 in animal models. A meta-analysis was conducted using databases such as PubMed, EMBASE, Springer, and Web of Science. The quality of the selected publications was estimated using the SYRCLE guidelines to ensure credibility and consistency of the research. Continuous variables were measured using mean difference or standardized mean difference (SMD), with a 95% confidence interval (CI) calculated. Ten randomized controlled animal experiments were included in this analysis, utilizing different general anesthetics such as sevoflurane and propofol compared to untreated control groups. The results consistently demonstrated a significant increase in GFAP (SMD = 0.41, 95% CI: 0.09, 0.72, P = 0.01) and Iba-1 (SMD = 0.43, 95% CI: 0.04, 0.83, P = 0.03) expression in the general anesthetic-treated groups, suggesting a neuroinflammatory response induced by these agents. Assessment of publication bias revealed no significant bias in the included studies. This meta-analysis highlights the impact of general anesthetics on GFAP expression in animal models, emphasizing the importance of understanding the neuroinflammatory response associated with anesthesia administration. Further research is warranted to elucidate the underlying molecular pathways and explore possible therapeutic interventions to mitigate adverse effects associated with anesthesia administration.

Sevoflurane anesthesia reduces the expression of inflammatory response genes and β-site amyloid precursor protein-cleaving enzyme in hippocampi of diabetic mice

Diabetes and inhaled anesthesia are associated with an increased likelihood of developing postoperative cognitive dysfunction in humans and animal models, but the mechanisms are unclear. This study aimed to investigate the effect and mechanism of sevoflurane anesthesia on cognitive function in diabetic (DM) mice. Spontaneously diabetic db/db and control db/m mice were subject to sevoflurane anesthesia or allowed to breathe air, respectively. The Morris water maze test as spatial learning and novel object recognition test as recognition memory were performed. The expression of inflammatory cytokines and neurotoxicity-related genes in the hippocampus of four groups was measured using real-time PCR. The expression level of neurotoxicity and neuroprotection-related proteins in DM mice hippocampus were estimated using Western blot assay. It is found that DM mice developed cognitive impairment; however, the cognitive impairment was not exacerbated in sevoflurane-exposed mice. Sevoflurane anesthesia led to a decrease in mRNA levels of inflammatory cytokines in DM mice hippocampi, including interleukin 17 (IL-17), C-C motif chemokine (CCL20), CCL7 as well as high mobility group box 1 and beta-site amyloid-β cleaving enzyme 1; and no effect was observed on the expression of neurotoxicity genes, including amyloid precursor protein, choline O-acetyltransferase, tumor necrosis factor, alpha-induced protein 1, B-cell lymphoma 2 and estrogen receptor 2. In addition, we observed elevated phosphorylation of cAMP response element-binding protein in DM mice exposed to sevoflurane anesthesia. In conclusion, sevoflurane did not exacerbate DM-associated cognitive impairment.

Celastrol attenuates HFD-induced obesity and improves metabolic function independent of adiponectin signaling

Backgound: Celastrol, a leptin sensitiser, has been shown to inhibit food intake and reduce body weight in diet-induced obese mice, making it a potential treatment for obesity and metabolic diseases. Adiponectin signalling has been reported to play an important role in the treatment of obesity, inflammation, and non-alcoholic fatty liver disease.Materials and methods: Wild-type (WT) and AdipoR1 knockout (AdipoR1-/-) mice were placed on a chow diet or a high-fat diet (HFD) and several metabolic parameters were measured. Celastrol was then administered to the HFD-induced mice and the response of WT and AdipoR1-/- mice to celastrol in terms of body weight, blood glucose, and food intake was also recorded.Results: AdipoR1 knockout caused elevated blood glucose and lipids, impaired glucose tolerance and insulin resistance in mice, as well as increased susceptibility to HFD-induced obesity. After 14 days of treatment, WT and AdipoR1-/- mice showed significant reductions in body weight and blood glucose and improvements in glucose tolerance.Conclusion: The present study demonstrated that AdipoR1 plays a critical role in metabolic regulation and that the improvement of weight and metabolic function by celastrol is independent of the AdipoR1-mediated signalling pathway.

The therapeutic potential of triptolide and celastrol in neurological diseases

Neurological diseases are complex diseases affecting the brain and spinal cord, with numerous etiologies and pathogenesis not yet fully elucidated. Tripterygium wilfordii Hook. F. (TWHF) is a traditional Chinese medicine with a long history of medicinal use in China and is widely used to treat autoimmune and inflammatory diseases such as systemic lupus erythematosus and rheumatoid arthritis. With the rapid development of modern technology, the two main bioactive components of TWHF, triptolide and celastrol, have been found to have anti-inflammatory, immunosuppressive and anti-tumor effects and can be used in the treatment of a variety of diseases, including neurological diseases. In this paper, we summarize the preclinical studies of triptolide and celastrol in neurological diseases such as neurodegenerative diseases, brain and spinal cord injury, and epilepsy. In addition, we review the mechanisms of action of triptolide and celastrol in neurological diseases, their toxicity, related derivatives, and nanotechnology-based carrier system.

Neuroprotective Effects of Celastrol in Neurodegenerative Diseases-Unscramble Its Major Mechanisms of Action and Targets

There are rarely new therapeutic breakthroughs present for neurodegenerative diseases in the last decades. Thus, new effective drugs are urgently needed for millions of patients with neurodegenerative diseases. Celastrol, a pentacyclic triterpenoid compound, is one of the main active ingredients isolated from Tripterygium wilfordii Hook. f. that has multiple biological activities. Recently, amount evidence indicates that celastrol exerts neuroprotective effects and holds therapeutic potential to serve as a novel agent for neurodegenerative diseases. This review focuses on the therapeutic efficacy and major regulatory mechanisms of celastrol to rescue damaged neurons, restore normal cognitive and sensory motor functions in neurodegenerative diseases. Importantly, we highlight recent progress regarding identification of the drug targets of celastrol by using advanced quantitative chemical proteomics technology. Overall, this review provides novel insights into the pharmacological activities and therapeutic potential of celastrol for incurable neurodegenerative diseases.

Celastrol inhibits the proliferation and angiogenesis of high glucose-induced human retinal endothelial cells

Background

Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes. Celastrol plays a certain role in the improvement of various diabetes complications. Therefore, this study aimed to explore whether celastrol inhibited the proliferation and angiogenesis of high glucose (HG)-induced human retinal endothelial cells (hRECs) by down-regulating the HIF1/VEGF signaling pathway.

Methods

The viability and proliferation of hRECs treated with glucose, celastrol or dimethyloxallyl glycine (DMOG) were analyzed by MTT assay. The invasion and tube formation ability of hRECs treated with glucose, celastrol or DMOG were in turn detected by transwell assay and tube formation assay. The expression of HIF1α and VEGF in hRECs after indicated treatment was analyzed by Western blot analysis and RT-qPCR analysis and ICAM-1 expression in hRECs after indicated treatment was detected by immunofluorescence assay

Results

HG induction promoted the proliferation, invasion and tube formation ability and increased the expression of HIF-1α and VEGF of hRECs, which were gradually suppressed by celastrol changing from 0.5 to 2.0 μM. DMOG was regarded as a HIF1α agonist, which attenuated the effect of celastrol on HG-induced hRECs.

Conclusion

Celastrol inhibited the proliferation and angiogenesis of HG-induced hRECs by down-regulating the HIF1α/VEGF signaling pathway.

Potential medicinal value of celastrol and its synthesized analogues for central nervous system diseases

The central nervous system (CNS) is a vital part of the human nervous system, and the incidence of CNS disease is increasing year by year, which has become a major public health problem and a prominent social problem. At present, the drugs most commonly used in the clinic are receptor regulators, and neurotransmitter inhibitors, but they are accompanied by serious side effects. Therefore, the identification of new drugs and treatment strategies for CNS disease has been a research hotspot in the medical field. Celastrol, a highly bio-active pentacyclic triterpenoid isolated from Tripterygium wilfordii Hook. F, has been proved to have a wide range of pharmacological effects, such as anti-inflammation, immunosuppression, anti-obesity and anti-tumor activity. However, due to its poor water solubility, low bioavailability and toxicity, the clinical development and trials of celastrol have been postponed. However, in recent years, the extensive medical value of celastrol in the treatment of CNS diseases such as nervous system tumors, Alzheimer's disease, Parkinson's disease, cerebral ischemia, multiple sclerosis, spinal cord injury, and amyotrophic lateral sclerosis has gradually attracted intensive attention worldwide. In particular, celastrol has non-negligible anti-tumor efficacy, and as there are no 100% effective anti-tumor drugs, the study of its structural modification to obtain better leading compounds with higher efficiency and lower toxicity has aroused strong interest in pharmaceutical chemists. In this review, research progress on celastrol in CNS diseases and the synthesis of celastrol-type triterpenoid analogues and their application evaluation in disease models, such as CNS diseases and autotoxicity-related target organ cancers in the past decade are summarized in detail, in order to provide reference for future better application in the treatment of CNS diseases.

Minimal effects from a single exposure to sevoflurane in adult male and female Sprague-Dawley rats

Many people undergo procedures requiring general anesthesia each day and adverse cognitive effects have been reported in response to that anesthesia. Postoperative Cognitive Dysfunction (POCD) may occur in as many as 80% of adults during the first post-surgical week and can have lasting effects. Here, the cognitive and motor effects of sevoflurane exposure in Sprague-Dawley rats was examined along with body weights, blood oxygen saturation, heart rate, and body temperature. Male and female rats were exposed to 2.5% sevoflurane or medical grade air for one hour at postnatal day 115. Beginning the following day, rats began a series of behavioral tests examining locomotor activity, motor coordination, novel object recognition, and spatial learning and memory in a water maze. Blood oxygen saturation, heart rate, and body temperature were not affected by the sevoflurane exposure. A slight effect on locomotor activity was detected, but no effects on motor coordination, novel object recognition, or spatial learning and memory were observed. Brain weights following behavioral testing did not differ. The results reported here along with existing literature suggest sevoflurane is largely without effects on later cognition in adult rodents when exposure is of a relatively short duration and at a relatively low concentration.

Frequency of oligosymptomatic gastrointestinal tract diseases and its relation to insulin-like growth factor I in idiopathic (non-GH-deficient) short stature children

INTRODUCTION

There is a discussion about growth hormone therapy in idiopathic short stature (ISS) children. To diagnose ISS, it is necessary to exclude other diseases; gastrointestinal tract diseases (GIDs) are among them. However, GID symptoms may be scarce. The aim of the study was to evaluate the frequency of unexpected oligosymptomatic GIDs in ISS and assess their influence on auxological parameters and insulin-like growth factor I (IGF-I) concentration.

MATERIAL AND METHODS

The analysis included 101 children with ISS and 95 controls. All patients were tested for celiac disease (CD), inflammatory bowel disease (IBD), lactose malabsorption (LM), cystic fibrosis (CF), Helicobacter pylori (HP) and Ascaris sp. (Asc) infections, as well as Candida albicans (Calb) colonization, by applying simple blood and stool tests and gastrofiberoscopy.

RESULTS

In 75.2% of short children, one or more than one GIDs listed above were diagnosed, with the highest frequency of: Calb (46.5%), LM (33.7%), HP (24.7%) and/or Asc (21.8%). The incidence of GIDs was significantly higher than in the control group. The GID frequency increases with the age of children. In most ISS children, the IGF-I SDS was below -1.0 and it was the lowest in children with HP (p < 0.05).

CONCLUSIONS

High frequency of unexpected oligosymptomatic GIDs in children diagnosed with ISS indicates the need to search for gastrointestinal (GI) causes in each case of short stature in children. The pathomechanisms responsible for short stature in these cases may vary, although it seems that reduced production of IGF-I plays an important role.

Early Celastrol Administration Prevents Ketamine-Induced Psychotic-Like Behavioral Dysfunctions, Oxidative Stress and IL-10 Reduction in The Cerebellum of Adult Mice

Administration of subanesthetic doses of ketamine during brain maturation represents a tool to mimic an early insult to the central nervous system (CNS). The cerebellum is a key player in psychosis pathogenesis, to which oxidative stress also contributes. Here, we investigated the impact of early celastrol administration on behavioral dysfunctions in adult mice that had received ketamine (30 mg/kg i.p.) at postnatal days (PNDs) 7, 9, and 11. Cerebellar levels of 8-hydroxydeoxyguanosine (8-OHdG), NADPH oxidase (NOX) 1 and NOX2, as well as of the calcium-binding protein parvalbumin (PV), were also assessed. Furthermore, celastrol effects on ketamine-induced alterations of proinflammatory (TNF-α, IL-6 and IL-1β) and anti-inflammatory (IL-10) cytokines in this brain region were evaluated. Early celastrol administration prevented ketamine-induced discrimination index decrease at adulthood. The same was found for locomotor activity elevations and increased close following and allogrooming, whereas no beneficial effects on sniffing impairment were detected. Ketamine increased 8-OHdG in the cerebellum of adult mice, which was also prevented by early celastrol injection. Cerebellar NOX1 levels were enhanced at adulthood following postnatal ketamine exposure. Celastrol per se induced NOX1 decrease in the cerebellum. This effect was more significant in animals that were early administered with ketamine. NOX2 levels did not change. Ketamine administration did not affect PV amount in the cerebellum. TNF-α levels were enhanced in ketamine-treated animals; however, this was not prevented by early celastrol administration. While no changes were observed for IL-6 and IL-1β levels, ketamine determined a reduction of cerebellar IL-10 expression, which was prevented by early celastrol treatment. Our results suggest that NOX inhibition during brain maturation prevents the development of psychotic-like behavioral dysfunctions, as well as the increased cerebellar oxidative stress and the reduction of IL-10 in the same brain region following ketamine exposure in postnatal life. This opens novel neuroprotective opportunities against early detrimental insults occurring during brain development.

Celastrol inhibits migration, proliferation and transforming growth factor-β2-induced epithelial-mesenchymal transition in lens epithelial cells

AIM

To investigate the mechanism of celastrol in inhibiting lens epithelial cells (LECs) fibrosis, which is the pathological basis of cataract.

METHODS

Human LEC line SRA01/04 was treated with celastrol and transforming growth factor-β2 (TGF-β2). Wound-healing assay, proliferation assay, flow cytometry, real-time polymerase chain reaction (PCR), Western blot and immunocytochemical staining were used to detect the pathological changes of celastrol on LECs. Then, we cultured Sprague-Dawley rat lens in medium as a semi-in vivo model to find the function of celastrol further.

RESULTS

We found that celastrol inhibited the migration of LECs, as well as proliferation (P<0.05). In addition, it induced the G2/M phase arrest by cell cycle-related proteins (P<0.01). Moreover, celastrol inhibited epithelial-mesenchymal transition (EMT) by the blockade of TGF-β/Smad and Jagged/Notch signaling pathways.

CONCLUSION

Our study demonstrates that celastrol could inhibit TGF-β2-induced lens fibrosis and raises the possibility that celastrol could be a potential novel drug in prevention and treatment of fibrotic cataract.

Modulation of Lipid Metabolism by Celastrol

Hyperlipidemia, characterized by high serum lipids, is a risk factor for cardiovascular disease. Recent studies have identified an important role for celastrol, a proteasome inhibitor isolated from Tripterygium wilfordii Hook. F., in obesity-related metabolic disorders. However, the exact influences of celastrol on lipid metabolism remain largely unknown. Celastrol inhibited the terminal differentiation of 3T3-L1 adipocytes and decreased the levels of triglycerides in wild-type mice. Lipidomics analysis revealed that celastrol increased the metabolism of lysophosphatidylcholines (LPCs), phosphatidylcholines (PCs), sphingomyelins (SMs), and phosphatidylethanolamines (PEs). Further, celastrol reversed the tyloxapol-induced hyperlipidemia induced associated with increased plasma LPCs, PCs, SMs, and ceramides (CMs). Among these lipids, LPC(16:0), LPC(18:1), PC(22:2/15:0), and SM(d18:1/22:0) were also decreased by celastrol in cultured 3T3-L1 adipocytes, mice, and tyloxapol-treated mice. The mRNAs encoded by hepatic genes associated with lipid synthesis and catabolism, including Lpcat1, Pld1, Smpd3, and Sptc2, were altered in tyloxapol-induced hyperlipidemia, and significantly recovered by celastrol treatment. The effect of celastrol on lipid metabolism was significantly reduced in Fxr-null mice, resulting in decreased Cers6 and Acer2 mRNAs compared to wild-type mice. These results establish that FXR was responsible in part for the effects of celastrol in controlling lipid metabolism and contributing to the recovery of aberrant lipid metabolism in obesity-related metabolic disorders.

Effect of different charges of modified electroconvulsive seizure on the cognitive behavior in stressed rats: Effects of GluR1 phosphorylation and CaMKIIα activity

Electroconvulsive therapy (ECT) is an efficient therapy for major depression and modern ECT requires anesthesia to enhance safety. However, the commonly used anesthetic, propofol, may weaken the treatment efficacy. A recent study confirmed that ketamine rapidly reduced the symptoms of depression in affected patients. A previous study found that electroconvulsive seizure (ECS), the animal model for ECT, under anesthesia of low-dose ketamine combined with propofol could enhance the antidepressant efficacy and improve the cognitive performance. The present study aimed to investigate the responses to different charges (0, 60, 120, 180 or 240 mC) of ECS under compound anesthetics, ketamine combined with propofol, in stressed rats and the underlying mechanisms to aid in optimization of treatment regimens. The results indicated that ECS exhibited an improved antidepressant effects at 120 mC compared with 60 mC, however, no significant differences in antidepressant effects were identified among the 120, 180 and 240 mC groups. Furthermore, rats subjected to ECS at 120 mC exhibited the best cognitive performance. The phosphorylation levels of calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) at Thr286, glutamate receptor 1 (GluR1) at Ser831 and cAMP-response element-binding protein (CREB) at the Ser133 were higher in the 120-mC group compared with all other groups. These results indicated that the ECS at medium intensity (120 mC) with administration of compound anesthetics may exert an improved therapeutic effect on depression compared with other intensities (0, 60, 180 and 240 mC). The results also suggested that the improvement in cognitive function in stressed rats may be attributed to the phosphorylation of CaMKIIα (Thr286), GluR1 (Ser831) and CREB (Ser133).