Hirsutine ameliorates hepatic and cardiac insulin resistance in high-fat diet-induced diabetic mice and in vitro models

Single-Atom Ce-N-C Nanozyme Ameliorates Type 2 Diabetes Mellitus by Improving Glucose Metabolism Disorders and Reducing Oxidative Stress

Type 2 diabetes mellitus (T2DM) as a chronic metabolic disease has become a global public health problem. Insulin resistance (IR) is the main pathogenesis of T2DM. Oxidative stress refers to an imbalance between free radical production and the antioxidant system, causing insulin resistance and contributing to the development of T2DM via several molecular mechanisms. Besides, the reduction in hepatic glycogen synthesis also leads to a decrease in peripheral insulin sensitivity. Thus, reducing oxidative stress and promoting glycogen synthesis are both targets for improving insulin resistance and treating T2DM. The current study aims to investigate the pharmacological effects of single-atom Ce-N-C nanozyme (SACe-N-C) on the improvement of insulin resistance and to elucidate its underlying mechanisms using HFD/STZ-induced C57BL/6J mice and insulin-resistant HepG2 cells. The results indicate that SACe-N-C significantly improves hepatic glycogen synthesis and reduces oxidative stress, as well as pancreatic and liver injury. Specifically, compared to the T2DM model group, fasting blood glucose decreased by 29%, hepatic glycogen synthesis increased by 17.13%, and insulin secretion increased by 18.87%. The sod and GPx in the liver increased by 17.80% and 25.28%, respectively. In terms of mechanism, SACe-N-C modulated glycogen synthesis through the PI3K/AKT/GSK3β signaling pathway and activated the Keap1/Nrf2 pathway to alleviate oxidative stress. Collectively, this study suggests that SACe-N-C has the potential to treat T2DM.

Cynomorium songaricum: UHPLC/ESI-LTQ-Orbitrap-MS analysis and mechanistic study on insulin sensitivity of a flavonoid-enriched fraction

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by elevated blood glucose levels, posing a significant global health concern due to its increasing prevalence. Insulin resistance (IR) plays a major role in the development of T2DM and is often linked to factors such as obesity, physical inactivity, and a sedentary lifestyle. Recently, there has been growing interest in exploring the potential of natural products for improving insulin sensitivity and glucose metabolism. Among these, Cynomorium songaricum Rupr., an edible parasitic plant, has shown promising antidiabetic effects. However, research on its beneficial effects on IR is still nascent. Therefore, this study aims to investigate the application of a Cynomorium songaricum flavonoid-enriched fraction (CSF) in the treatment of IR in T2DM, along with elucidating the chemical and biochemical mechanisms involved.

METHOD

First, UHPLC/ESI-LTQ-Orbitrap-MS was utilized to perform a chemical profiling of CSF. Subsequently, glycogen synthesis, gluconeogenesis and glucose consumption assays were conducted on HepG2 cells with a high glucose high insulin-induced IR model to illustrate the favorable impacts of CSF on IR. Then, an innovative network pharmacology analysis was executed to predict the potential chemical components and hub genes contributing to CSF's protective effect against IR. To further elucidate molecular interactions, molecular docking studies were performed, focusing on the binding interactions between active constituents of CSF and crucial targets. Additionally, an RNA-sequencing assay was employed to uncover the underlying biochemical signaling pathway responsible for CSF's beneficial effects. To validate these findings, western blot and qPCR assays were employed to verify the pathways related to IR and the potential signaling cascades leading to the amelioration of IR.

RESULTS

The UHPLC/ESI-LTQ-Orbitrap-MS analysis successfully identified a total of thirty-six flavonoids derived from CSF. Moreover, CSF was shown to significantly improve glycogen synthesis and glucose consumption as well as inhibit gluconeogenesis in HepG2 cells of IR. An innovative network pharmacology analysis unveiled key hub genes-AKT1 and PI3K-integral to metabolic syndrome-related signaling pathways, which contributed to the favorable impact of CSF against IR. Noteworthy active ingredients including quercetin, ellagic acid and naringenin were identified as potential contributors to these effects. The results of western blot and qPCR assays provided compelling evidence that CSF improved insulin sensitivity by modulating the PI3K-Akt signaling pathway. Subsequent RNA-sequencing analysis, in tandem with western blot assays, delved deeper into the potential mechanisms underlying CSF's advantageous effects against IR, potentially associated with the enhancement of endoplasmic reticulum (ER) proteostasis.

CONCLUSION

CSF exhibited a remarkable ability to enhance insulin sensitivity in the IR model of HepG2 cells. This was evident through enhancements in glycogen synthesis and glucose consumption, along with its inhibitory impact on gluconeogenesis. Furthermore, CSF demonstrated an improvement in the insulin-mediated PI3K-Akt signaling pathway. The potential active constituents were identified as quercetin, ellagic acid and naringenin. The underlying biochemical mechanisms responsible for CSF's beneficial effects against IR were closely linked to its capacity to mitigate ER stress, thereby offering a comprehensive understanding of its protective action.

Aberrant activation of p53-TRIB3 axis contributes to diabetic myocardial insulin resistance and sulforaphane protection

INTRODUCTION

Insulin resistance (IR) is associated with multiple pathological features. Although p53- or TRIB3-orchestrated IR is extensively studied in adipose tissue and liver, the role of p53-TRIB3 axis in myocardial IR remains unknown, and more importantly target-directed therapies of myocardial IR are missing.

OBJECTIVES

Considering the beneficial effects of sulforaphane (SFN) on cardiovascular health, it is of particular interest to explore whether SFN protects against myocardial IR with a focus on the regulatory role of p53-TRIB3 axis.

METHODS

Mouse models including cardiac specific p53-overexpressing transgenic (p53-cTg) mice and Trib3 knockout (Trib3-KO) mice, combined with primary cardiomyocytes treated with p53 activator (nutlin-3a) and inhibitor (pifithrin-α, PFT-α), or transfected with p53-shRNA and Trib3-shRNA, followed by multiple molecular biological methodologies, were used to investigate the role of p53-TRIB3 axis in SFN actions on myocardial IR.

RESULTS

Here, we report that knockdown of p53 rescued cardiac insulin-stimulated AKT phosphorylation, while up-regulation of p53 by nutlin-3a or p53-cTg mice blunted insulin sensitivity in cardiomyocytes under diabetic conditions. Diabetic attenuation of AKT-mediated cardiac insulin signaling was markedly reversed by SFN in p53-Tgfl/fl mice, but not in p53-cTg mice. Importantly, we identified TRIB3 was elevated in p53-cTg diabetic mice, and confirmed the physical interaction between p53 and TRIB3. Trib3-KO diabetic mice displayed improved insulin sensitivity in the heart. More specifically, the AMPKα-triggered CHOP phosphorylation and degradation were essential for p53 on the transcriptional regulation of Trib3.

CONCLUSION

Overall, these results indicate that inhibiting the p53-TRIB3 pathway by SFN plays an unsuspected key role in the improvement of myocardial IR, which may be a promising strategy for attenuating diabetic cardiomyopathy (DCM) in diabetic patients.

GPR30 selective agonist G-1 induced insulin resistance in ovariectomized mice on high fat diet and its mechanism

BACKGROUND

Previous in vivo and in vitro studies have demonstrated that estrogen receptor agonist G-1 regulates glucose and lipid metabolism. This study focused on the effects of G-1 on cardiometabolic syndrome and anti-obesity under a high fat diet (HFD).

METHODS

Bilateral ovariectomized female mice were fed an HFD for 6 weeks, and treated them with G-1. A cardiomyocyte insulin resistance model was used to simulate the in vivo environment. The main outcome measures were blood glucose, body weight, and serum insulin levels to assess insulin resistance, while cardiac function and degree of fibrosis were assessed by cardiac ultrasound and pathological observations. We also examined the expression of p-AMPK, p-AKT, and GLUT4 in mice hearts and in vitro models to explore the mechanism by which G-1 regulates insulin signaling.

RESULTS

G-1 reduced body weight in mice on an HFD, but simultaneously increased blood glucose and promoted insulin resistance, resulting in myocardial damage. This damage included disordered cardiomyocytes, massive accumulation of glycogen, extensive fibrosis of the heart, and thickening of the front and rear walls of the left ventricle. At the molecular level, G-1 enhances gluconeogenesis and promotes glucose production by increasing the activity of pyruvate carboxylase (PC) while inhibiting GLUT4 translocation via the AMPK/TBC1D1 pathway, thereby limiting glucose uptake.

CONCLUSION

Despite G-1's the potential efficacy in weight reduction, the concomitant induction of insulin resistance and cardiac impairment in conjunction with an HFD raises significant concerns. Therefore, comprehensive studies of its safety profile and effects under specific conditions are essential prior to clinical use.

Establishment of an animal model of immune-related adverse events induced by immune checkpoint inhibitors

OBJECTIVE

Immunotherapy, specifically immune checkpoint inhibitors (ICIs), has revolutionized cancer treatment. However, it can also cause immune-related adverse events (irAEs). This study aimed to develop a clinically practical animal model of irAEs using BALB/c mice.

METHODS

Subcutaneous tumors of mouse breast cancer 4T1 cells were generated in inbred BALB/c mice. The mice were treated with programmed death-1 (PD-1) and cytotoxic t-lymphocyte antigen 4 (CTLA-4) inhibitors once every 3 days for five consecutive administration cycles. Changes in tumor volume and body weight were recorded. Lung computed tomography (CT) scans were conducted. The liver, lungs, heart, and colon tissues of the mice were stained with hematoxylin-eosin (H&E) staining to observe inflammatory infiltration and were scored. Serum samples were collected, and enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of ferritin, glutamic-pyruvic transaminase (ALT), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), and interleukin-6 (IL-6). Mouse liver and lung cell suspensions were prepared, and changes in macrophages, T cells, myeloid-derived suppressor cells (MDSCs), and regulatory (Treg) cells were detected by flow cytometry.

RESULTS

Mice treated with PD-1 and CTLA-4 inhibitors showed significant reductions in tumor volume and body weight. The tissue inflammatory scores in the experimental group were significantly higher than those in the control group. Lung CT scans of mice in the experimental group showed obvious inflammatory spots. Serum levels of ferritin, IL-6, TNF-α, IFN-γ, and ALT were significantly elevated in the experimental group. Flow cytometry analysis revealed a substantial increase in CD3+T cells, Treg cells, and macrophages in the liver and lung tissues of mice in the experimental group compared with the control group, and the change trend of MDSCs was opposite.

CONCLUSIONS

The irAE-related animal model was successfully established in BALB/c mice using a combination of PD-1 and CTLA-4 inhibitors through multiple administrations with clinical translational value and practical. This model offers valuable insights into irAE mechanisms for further investigation.

Unveiling the Nutritional Veil of Sulforaphane: With a Major Focus on Glucose Homeostasis Modulation

Abnormal glucose homeostasis is associated with metabolic syndromes including cardiovascular diseases, hypertension, type 2 diabetes mellitus, and obesity, highlighting the significance of maintaining a balanced glucose level for optimal biological function. This highlights the importance of maintaining normal glucose levels for proper biological functioning. Sulforaphane (SFN), the primary bioactive compound in broccoli from the Cruciferae or Brassicaceae family, has been shown to enhance glucose homeostasis effectively while exhibiting low cytotoxicity. This paper assesses the impact of SFN on glucose homeostasis in vitro, in vivo, and human trials, as well as the molecular mechanisms that drive its regulatory effects. New strategies have been proposed to enhance the bioavailability and targeted delivery of SFN in order to overcome inherent instability. The manuscript also covers the safety evaluations of SFN that have been documented for its production and utilization. Hence, a deeper understanding of the favorable influence and mechanism of SFN on glucose homeostasis, coupled with the fact that SFN is abundant in the human daily diet, may ultimately offer theoretical evidence to support its potential use in the food and pharmaceutical industries.

Activation of NRF2 by epiberberine improves oxidative stress and insulin resistance in T2DM mice and IR-HepG2 cells in an AMPK dependent manner

ETHNOPHARMACOLOGICAL RELEVANCE

Phytochemical compounds offer a distinctive edge in diabetes management, attributed to their multifaceted target mechanisms and minimal toxicological profiles. Epiberberine (EPI), an alkaloid derived from plants of the Rhizoma Coptidis, has been reported to have antidiabetic effects. However, the underlying molecular mechanism of EPI are not fully elucidated.

AIM OF THE STUDY

This study explored the anti-diabetic effects of EPI and the role of the NRF2/AMPK signaling pathway in improving insulin resistance.

MATERIALS AND METHODS

We utilized two distinct models: in vivo, we employed mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet (HFD) and streptozotocin (STZ) to conduct a range of assessments including measuring physical parameters, conducting biochemical analyses, examining histopathology, and performing Western blot tests. In parallel, in vitro experiments were carried out using insulin resistance (IR)-HepG2 cells, through which we conducted a CCK8 assay, glucose uptake tests, Western blot analyses, and flow cytometry studies.

RESULTS

In the EPI-treated group of T2DM mice, there was a significant reduction in hyperglycemia, IR, and hyperlipidemia, accompanied by beneficial changes in the liver and pancreas, as well as enhanced glucose uptake in IR-HepG2 cells. Herein, our finding also provided evidence that EPI could increase the expression of GLUT4 and activated the IRS-1/PI3K/AKT insulin signaling pathway to improve IR in vitro and in vivo. Moreover, EPI alleviated oxidative stress by enhancing SOD and GPX-px activity, decreasing reactive oxygen species (ROS) and malondialdehyde (MDA) content, and promoting nuclear factor (erythroid-derived 2)-like 2 (NRF2), total NRF2, NAD(P)H-quinone oxidoreductase (NQO1) and heme oxygenase-1 (HO-1) expression in the liver tissue of T2DM mice and IR-HepG2 cells. Furthermore, EPI decreased oxidative stress and improved IR, but these benefits were nullified by siNRF2 transfection. In particular, AMP-activated protein kinase (AMPK) deficiency by short-hairpin RNA (shRNA) partially reversed the effects of EPI on nuclear transcription, oxidative stress, and IR of NRF2 in IR-HepG2 cells.

CONCLUSIONS

Taken together, EPI activated NRF2-dependent AMPK cascade to protect T2DM from oxidative stress, thereby alleviating IR.

A novel mouse model of familial combined hyperlipidemia and atherosclerosis

Within the context of residual cardiovascular risk in post-statin era, emerging evidence from epidemiologic and human genetic studies have demonstrated that triglyceride (TG)-rich lipoproteins and their remnants are causally related to cardiovascular risk. While, carriers of loss-of-function mutations of ApoC3 have low TG levels and are protected from cardiovascular disease (CVD). Of translational significance, siRNAs/antisense oligonucleotide (ASO) targeting ApoC3 is beneficial for patients with atherosclerotic CVD. Therefore, animal models of atherosclerosis with both hypercholesterolemia and hypertriglyceridemia are important for the discovery of novel therapeutic strategies targeting TG-lowering on top of traditional cholesterol-lowering. In this study, we constructed a novel mouse model of familial combined hyperlipidemia through inserting a human ApoC3 transgene (hApoC3-Tg) into C57BL/6 J mice and injecting a gain-of-function variant of adeno-associated virus-proprotein convertase subtilisin/kexin type 9 (AAV-PCSK9)-D377Y concurrently with high cholesterol diet (HCD) feeding for 16 weeks. In the last 10 weeks, hApoC3-Tg mice were orally treated with a combination of atorvastatin (10 mg·kg-1·d-1) and fenofibrate (100 mg·kg-1·d-1). HCD-treated hApoC3-Tg mice demonstrated elevated levels of serum TG, total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C). Oral administration of atorvastatin and fenofibrate significantly decreased the plaque sizes of en face aorta, aortic sinus and innominate artery accompanied by improved lipid profile and distribution. In summary, this novel mouse model is of considerable clinical relevance for evaluation of anti-atherosclerotic drugs by targeting both hypercholesterolemia and hypertriglyceridemia.

Metabolites of traditional Chinese medicine targeting PI3K/AKT signaling pathway for hypoglycemic effect in type 2 diabetes

Type 2 diabetes mellitus is a chronic metabolic disease characterized by insulin resistance, with high morbidity and mortality worldwide. Due to the tightly intertwined connection between the insulin resistance pathway and the PI3K/AKT signaling pathway, regulating the PI3K/AKT pathway and its associated targets is essential for hypoglycemia and the prevention of type 2 diabetes mellitus. In recent years, metabolites isolated from traditional Chinese medicine has received more attention and acceptance for its superior bioactivity, high safety, and fewer side effects. Meanwhile, numerous in vivo and in vitro studies have revealed that the metabolites present in traditional Chinese medicine possess better bioactivities in regulating the balance of glucose metabolism, ameliorating insulin resistance, and preventing type 2 diabetes mellitus via the PI3K/AKT signaling pathway. In this article, we reviewed the literature related to the metabolites of traditional Chinese medicine improving IR and possessing therapeutic potential for type 2 diabetes mellitus by targeting the PI3K/AKT signaling pathway, focusing on the hypoglycemic mechanism of the metabolites of traditional Chinese medicine in type 2 diabetes mellitus and elaborating on the significant role of the PI3K/AKT signaling pathway in type 2 diabetes mellitus. In order to provide reference for clinical prevention and treatment of type 2 diabetes mellitus.

Innovative pharmacotherapy for hepatic metabolic and chronic inflammatory diseases in China

Liver disease constitutes a significant global health concern, particularly in China where it has distinctive characteristics. China grapples with a staggering 300 million cases, predominantly due to hepatitis B and metabolic non-alcoholic fatty liver disease. Additionally, hepatocellular carcinoma has become a prevalent which is a lethal type of cancer. Despite the scarcity of innovative treatment options, Chinese hepatologists and researchers have achieved notable breakthroughs in the prevention, diagnosis, management and treatment of liver diseases. Traditional Chinese medicines have found widespread application in the treatment of various liver ailments owing to their commendable pharmacological efficacy and minimal side effects. Furthermore, there is a growing body of research in extracellular vesicles, cell therapy and gene therapy, offering new hope in the fight against liver diseases. This paper provides a comprehensive overview of the epidemiological characteristics of liver diseases and the diverse array of treatments that Chinese scholars and scientists have pursued in critical field.

Isorhamnetin as a potential therapeutic agent for diabetes mellitus through PGK1/AKT activation

CONTEXT

Type 2 Diabetes Mellitus (T2D) is a significant health concern worldwide, necessitating novel therapeutic approaches beyond conventional treatments.

OBJECTIVE

To assess isorhamnetin's potential in improving insulin sensitivity and mitigating T2D characteristics through oxidative and glycative stress modulation.

MATERIALS AND METHODS

T2D was induced in mice with a high-fat diet and streptozotocin injections. Isorhamnetin was administered at 10 mg/kg for 12 weeks. HepG2 cells were used to examine in vitro effects on stress markers and insulin sensitivity. Molecular effects on the PGK1 and AKT signalling pathway were also analyzed.

RESULTS

The administration of isorhamnetin significantly impacted both in vivo and in vitro models. In HepG2 cells, oxidative and glycative stresses were markedly reduced, indicating a direct effect of isorhamnetin on cellular stress pathways, which are implicated in the deterioration of insulin sensitivity. Specifically, treated cells showed a notable decrease in markers of oxidative stress, such as malondialdehyde, and advanced glycation end products, highlighting isorhamnetin's antioxidant and antiglycative properties. In vivo, isorhamnetin-treated mice exhibited substantially lower fasting glucose levels compared to untreated T2D mice, suggesting a strong hypoglycemic effect. Moreover, these mice showed improved insulin responsiveness, evidenced by enhanced glucose tolerance and insulin tolerance tests. The molecular investigation revealed that isorhamnetin activated PGK1, leading to the activation of the AKT signalling pathway, crucial for promoting glucose uptake and reducing insulin resistance. This molecular action underscores the potential mechanism through which isorhamnetin exerts its beneficial effects in T2D management.

DISCUSSION

The study underscores isorhamnetin's multifaceted role in T2D management, emphasizing its impact on oxidative and glycative stress reduction and molecular pathways critical for insulin sensitivity.

CONCLUSION

Isorhamnetin presents a promising avenue for T2D treatment, offering a novel approach to enhancing insulin sensitivity and managing glucose levels through the modulation of key molecular pathways. Further research is needed to translate these findings into clinical practice.

Vitamin D Alleviates Type 2 Diabetes Mellitus by Mitigating Oxidative Stress-Induced Pancreatic β-Cell Impairment

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is a common metabolic disorder with rising incidence worldwide. This study explored the anti-T2DM role of vitamin D, thereby providing novel therapeutic strategies.

METHODS

C57BL/6 J mice and MIN6 cells were used to induce in vivo T2DM and damaged β-cell models, respectively. Body weights, fasting blood glucose, and fasting insulin were measured in mice. Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were conducted on mice. Lipid indices (TG, TC, LDL-C, and HDL-C) were detected in mouse serum. Hematoxylin-eosin staining was used to evaluate pancreatic tissue injury. ELISA was used to assess insulin and oxidative stress (OS) markers (MDA, GSH, and SOD) in mice and MIN6 cells. Production of ROS was detected in islet β-cells and MIN6 cells. Cell viability and apoptosis were evaluated using CCK-8 and flow cytometry, respectively. QRT-PCR and western blotting were used to detect pro-inflammatory factors (TNF-α and IL-6) and endoplasmic reticulum stress (ERS) markers (CHOP and GRP78), respectively.

RESULTS

Vitamin D reduced body weights, fasting blood glucose, and insulin and ameliorated glucose tolerance and insulin sensitivity in T2DM mice. Besides, vitamin D decreased serum TG, TC, LDL-C, and increased HDL-C in T2DM mice. Vitamin D inhibited pancreatic histopathological injury, cell apoptosis, OS, and β-cell decline in T2DM mice. Moreover, vitamin D alleviated cell death, insufficient insulin secretion, inflammation, OS, and ERS in damaged MIN6 cells. Notably, N-acetyl-L-cysteine (an OS inhibitor) enhanced these effects of vitamin D.

CONCLUSIONS

Vitamin D relieved T2DM symptoms by alleviating OS-induced β-cell impairment.

Inhibiting Rev-erbα-mediated ferroptosis alleviates susceptibility to myocardial ischemia-reperfusion injury in type 2 diabetes

The complex progression of type-2 diabetes (T2DM) may result in increased susceptibility to myocardial ischemia-reperfusion (IR) injury. IR injuries in multiple organs involves ferroptosis. Recently, the clock gene Rev-erbα has aroused considerable interest as a novel therapeutic target for metabolic and ischemic heart diseases. Herein, we investigated the roles of Rev-erbα and ferroptosis in myocardial IR injury during T2DM and its potential mechanisms. A T2DM model, myocardial IR and a tissue-specific Rev-erbα-/- mouse in vivo were established, and a high-fat high glucose environment with hypoxia-reoxygenation (HFHG/HR) in H9c2 were also performed. After myocardial IR, glycolipid profiles, creatine kinase-MB, AI, and the expression of Rev-erbα and ferroptosis-related proteins were increased in diabetic rats with impaired cardiac function compared to non-diabetic rats, regardless of the time at which IR was induced. The ferroptosis inhibitor ferrostatin-1 decreased AI in diabetic rats given IR and LPO levels in cells treated with HFHG/HR, as well as the expression of Rev-erbα and ACSL4. The ferroptosis inducer erastin increased AI and LPO levels and ACSL4 expression. Treatment with the circadian regulator nobiletin and genetically targeting Rev-erbα via siRNA or CRISPR/Cas9 technology both protected against severe myocardial injury and decreased Rev-erbα and ACSL4 expression, compared to the respective controls. Taken together, these data suggest that ferroptosis is involved in the susceptibility to myocardial IR injury during T2DM, and that targeting Rev-erbα could alleviate myocardial IR injury by inhibiting ferroptosis.

Natural products in non-alcoholic fatty liver disease (NAFLD): Novel lead discovery for drug development

With changing lifestyles, non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide. A substantial increase in the incidence, mortality, and associated burden of NAFLD-related advanced liver disease is expected. Currently, the initial diagnosis of NAFLD is still based on ultrasound and there is no approved treatment method. Lipid-lowering drugs, vitamin supplementation, and lifestyle improvement treatments are commonly used in clinical practice. However, most lipid-lowering drugs can produce poor patient compliance and specific adverse effects. Therefore, the exploration of bio-diagnostic markers and active lead compounds for the development of innovative drugs is urgently needed. More and more studies have reported the anti-NAFLD effects and mechanisms of natural products (NPs), which have become an important source for new drug development to treat NAFLD due to their high activity and low side effects. At present, berberine and silymarin have been approved by the US FDA to enter clinical phase IV studies, demonstrating the potential of NPs against NAFLD. Studies have found that the regulation of lipid metabolism, insulin resistance, oxidative stress, and inflammation-related pathways may play important roles in the process. With the continuous updating of technical means and scientific theories, in-depth research on the targets and mechanisms of NPs against NAFLD can provide new possibilities to find bio-diagnostic markers and innovative drugs. As we know, FXR agonists, PPARα agonists, and dual CCR2/5 inhibitors are gradually coming on stage for the treatment of NAFLD. Whether NPs can exert anti-NAFLD effects by regulating these targets or some unknown targets remains to be further studied. Therefore, the study reviewed the potential anti-NAFLD NPs and their targets. Some works on the discovery of new targets and the docking of active lead compounds were also discussed. It is hoped that this review can provide some reference values for the development of non-invasive diagnostic markers and new drugs against NAFLD in the clinic.

Hirsutine, an Emerging Natural Product with Promising Therapeutic Benefits: A Systematic Review

Fruits and vegetables are used not only for nutritional purposes but also as therapeutics to treat various diseases and ailments. These food items are prominent sources of phytochemicals that exhibit chemopreventive and therapeutic effects against several diseases. Hirsutine (HSN) is a naturally occurring indole alkaloid found in various Uncaria species and has a multitude of therapeutic benefits. It is found in foodstuffs such as fish, seafood, meat, poultry, dairy, and some grain products among other things. In addition, it is present in fruits and vegetables including corn, cauliflower, mushrooms, potatoes, bamboo shoots, bananas, cantaloupe, and citrus fruits. The primary emphasis of this study is to summarize the pharmacological activities and the underlying mechanisms of HSN against different diseases, as well as the biopharmaceutical features. For this, data were collected (up to date as of 1 July 2023) from various reliable and authentic literature by searching different academic search engines, including PubMed, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. Findings indicated that HSN exerts several effects in various preclinical and pharmacological experimental systems. It exhibits anti-inflammatory, antiviral, anti-diabetic, and antioxidant activities with beneficial effects in neurological and cardiovascular diseases. Our findings also indicate that HSN exerts promising anticancer potentials via several molecular mechanisms, including apoptotic cell death, induction of oxidative stress, cytotoxic effect, anti-proliferative effect, genotoxic effect, and inhibition of cancer cell migration and invasion against various cancers such as lung, breast, and antitumor effects in human T-cell leukemia. Taken all together, findings from this study show that HSN can be a promising therapeutic agent to treat various diseases including cancer.

Dihydro-Resveratrol Attenuates Oxidative Stress, Adipogenesis and Insulin Resistance in In Vitro Models and High-Fat Diet-Induced Mouse Model via AMPK Activation

Management of obesity has become a prevalent strategy for preventing the diseases closely integrated with excess body weight such as diabetes over the last half century. Searching for therapeutic agents acting on oxidative stress, adipogenesis and insulin resistance is considered as an efficient approach to control obesity-related diseases. The present study was designed to examine the in vitro and in vivo effects of dihydro-resveratrol (DR2), a naturally occurring compound from Dendrobium medicinal plants, on oxidative stress aggravation, adipogenesis, lipogenesis and insulin sensitivity. We utilized an in vitro 3T3-L1 adipocyte differentiation model to show that DR2 could reduce pre-adipocyte maturation by activation of AMPK/SIRT1 signaling proteins to inhibit p38MAPK proteins. With the use of in vitro oxidative-stress-induced hepatocytes and myoblasts models, DR2 was also shown to be able to reduce oxidative stress aggravation through mediation of Nrf2-related antioxidative cascade, reduce intracellular lipid accumulation through phosphorylation of ACC protein, reduce lipid peroxidation in hepatocytes and promote insulin sensitivity via activation of AKT protein in the insulin-resistant HepG2 cells and C2C12 cells. The effects of DR2 on adipogenesis, lipid accumulation, insulin resistance and blood glucose clearance were further demonstrated in the high-fat diet-induced obesity mouse model. Our in vitro and in vivo studies determined that DR2 could contain therapeutic potential for the treatment of obesity and type 2 diabetes.

Abnormalities of glucose and lipid metabolism in myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion injury is a common condition in cardiovascular diseases, and the mechanism of its occurrence involves multiple complex metabolic pathways and signaling pathways. Among these pathways, glucose metabolism and lipid metabolism play important roles in regulating myocardial energy metabolism. Therefore, this article focuses on the roles of glucose metabolism and lipid metabolism in myocardial ischemia-reperfusion injury, including glycolysis, glucose uptake and transport, glycogen metabolism and the pentose phosphate pathway; and triglyceride metabolism, fatty acid uptake and transport, phospholipid metabolism, lipoprotein metabolism, and cholesterol metabolism. Finally, due to the different alterations and development of glucose metabolism and lipid metabolism in myocardial ischemia-reperfusion, there are also complex interregulatory relationships between them. In the future, modulating the equilibrium between glucose metabolism and lipid metabolism in cardiomyocytes and ameliorating aberrations in myocardial energy metabolism represent highly promising novel strategies for addressing myocardial ischemia-reperfusion injury. Therefore, a comprehensive exploration of glycolipid metabolism can offer novel theoretical and clinical insights into the prevention and treatment of myocardial ischemia-reperfusion injury.

Alfuzosin ameliorates diabetes by boosting PGK1 activity in diabetic mice

AIMS

Diabetes mellitus (DM) has become a global problem, causing a huge economic burden. The purpose of this study is to find a new potential method and mechanism for the treatment of DM.

MAIN METHODS

The oxidation, glycation and insulin resistance cell models were built to screen the potential anti-diabetic chemicals. Then the DM mice were induced by the combination of high-fat diet (HFD) and intraperitoneal injection of streptozotocin (50 mg/kg) for five days. The alfuzosin (1.2 mg/kg) was administered by intraperitoneal injection once daily for sequential 12 weeks. Fasting blood glucose, blood lipid, oxidative stress and key markers of glucose metabolism were detected. PGK1/AKT/GLUT4 pathway related proteins were analyzed by Western blot.

KEY FINDINGS

Alfuzosin ameliorated oxidative stress, glycative stress and insulin resistance in HepG2 cells. Further, in a high-fat diet/streptozotocin (HFD/STZ)-induced diabetic mouse model, alfuzosin reduced fasting blood glucose, improved insulin sensitivity. Mechanically, alfuzosin activated PGK1 directly to stimulate the protein kinase B (AKT) signaling pathway, thus facilitating glucose uptake as well as improving insulin resistance.

SIGNIFICANCE

The present finding has shed a new light on the treatment of DM and provides validation for PGK1 as a therapeutic target for DM.

Update of Indoles: Promising molecules for ameliorating metabolic diseases

Obesity and metabolic disorders have gradually become public health-threatening problems. The metabolic disorder is a cluster of complex metabolic abnormalities which are featured by dysfunction in glucose and lipid metabolism, and results from the increasing prevalence of visceral obesity. With the core driving factor of insulin resistance, metabolic disorder mainly includes type 2 diabetes mellitus (T2DM), micro and macro-vascular diseases, non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and the dysfunction of gut microbiota. Strategies and therapeutic attention are demanded to decrease the high risk of metabolic diseases, from lifestyle changes to drug treatment, especially herbal medicines. Indole is a parent substance of numerous bioactive compounds, and itself can be produced by tryptophan catabolism to stimulate glucagon-like peptide-1 (GLP-1) secretion and inhibit the development of obesity. In addition, in heterocycles drug discovery, the indole scaffold is primarily found in natural compounds with versatile biological activity and plays a prominent role in drug molecules synthesis. In recent decades, plenty of natural or synthesized indole deriviatives have been investigated and elucidated to exert effects on regulating glucose hemeostasis and lipd metabolism. The aim of this review is to trace and emphasize the compounds containing indole scaffold that possess immense potency on preventing metabolic disorders, particularly T2DM, obesity and NAFLD, along with the underlying molecular mechanisms, therefore facilitate a better comprehension of their druggability and application in metabolic diseases.

Hepatocellular Carcinoma and Obesity, Type 2 Diabetes Mellitus, Cardiovascular Disease: Causing Factors, Molecular Links, and Treatment Options

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, which will affect more than a million people by the year 2025. However, current treatment options have limited benefits. Nonalcoholic fatty liver disease (NAFLD) is the fastest growing factor that causes HCC in western countries, including the United States. In addition, NAFLD co-morbidities including obesity, type 2 diabetes mellitus (T2DM), and cardiovascular diseases (CVDs) promote HCC development. Alteration of metabolites and inflammation in the tumor microenvironment plays a pivotal role in HCC progression. However, the underlying molecular mechanisms are still not totally clear. Herein, in this review, we explored the latest molecules that are involved in obesity, T2DM, and CVDs-mediated progression of HCC, as they share some common pathologic features. Meanwhile, several therapeutic options by targeting these key factors and molecules were discussed for HCC treatment. Overall, obesity, T2DM, and CVDs as chronic metabolic disease factors are tightly implicated in the development of HCC and its progression. Molecules and factors involved in these NAFLD comorbidities are potential therapeutic targets for HCC treatment.