Pharmacological Strategies for Insulin Sensitivity in Obesity and Cancer: Thiazolidinediones and Metformin

Improvement of chronic metabolic inflammation and regulation of gut homeostasis: Tea as a potential therapy

Chronic metabolic inflammation is a common mechanism linked to the development of metabolic disorders such as obesity, diabetes, and cardiovascular disease (CVD). Chronic metabolic inflammation often related to alterations in gut homeostasis, and pathological processes involve the activation of endotoxin receptors, metabolic reprogramming, mitochondrial dysfunction, and disruption of intestinal nuclear receptor activity. Recent investigations into homeostasis and chronic metabolic inflammation have revealed a novel mechanism which is characterized by a timing interaction involving multiple components and targets. This article explores the positive impact of tea consumption on metabolic health of populations, with a special focus on the improvement of inflammatory indicators and the regulation of gut microbiota. Studies showed that tea consumption is related to the enrichment of gut microbiota. The relative proportion of Firmicutes/Bacteroidetes (F/B) is altered, while the abundance of Lactobacillus, Bifidobacterium, and A. muciniphila increased significantly in most of the studies. Thus, tea consumption could provide potential protection from the development of chronic diseases by improving gut homeostasis and reducing chronic metabolic inflammation. The direct impact of tea on intestinal homeostasis primarily targets lipopolysaccharide (LPS)-related pathways. This includes reducing the synthesis of intestinal LPS, inhibiting LPS translocation, and preventing the binding of LPS to TLR4 receptors to block downstream inflammatory pathways. The TLR4/MyD88/NF-κB p65 pathway is crucial for anti-metaflammatory responses. The antioxidant properties of tea are linked to enhancing mitochondrial function and mitigating mitochondria-related inflammation by eliminating free radicals, inhibiting NLRP3 inflammasomes, and modulating Nrf2/ARE activity. Tea also contributes to safeguarding the intestinal barrier through various mechanisms, such as promoting the synthesis of short-chain fatty acids in the intestine, activating intestinal aryl hydrocarbon receptor (AhR) and farnesoid X receptor (FXR), and improving enteritis. Functional components that improve chronic metabolic inflammation include tea polyphenols, tea pigments, TPS, etc. Tea metabolites such as 4-Hydroxyphenylacetic acid and 3,4-Dihydroxyflavan derivatives, etc., also contribute to anti-chronic metabolic inflammation effects of tea consumption. The raw materials and processing technologies affect the functional component compositions of tea; therefore, consuming different types of tea may result in varying action characteristics and mechanisms. However, there is currently limited elaboration on this aspect. Future research should conduct in-depth studies on the mechanism of tea and its functional components in improving chronic metabolic inflammation. Researchers should pay attention to whether there are interactions between tea and other foods or drugs, explore safe and effective usage and dosage, and investigate whether there are individual differences in the tea-drinking population leading to different effects of tea intervention. Ultimately, the application of tea drinking could be a universal therapy for regulating intestinal homeostasis, anti-chronic metabolic inflammatory responses, and promoting metabolic health.

Current and emerging strategies for the prevention of hepatocellular carcinoma

Liver cancer is the third leading cause of cancer-related deaths globally, with incident cases expected to rise from 905,700 in 2020 to 1.4 million by 2040. Hepatocellular carcinoma (HCC) accounts for about 80% of all primary liver cancers. Viral hepatitis and chronic excessive alcohol consumption are major risk factors for HCC, but metabolic dysfunction-associated steatotic liver disease is also becoming a dominant cause. The increasing numbers of cases of HCC and changes in risk factors highlight the urgent need for updated and targeted prevention strategies. Preventive interventions encompass strategies to decrease the burden of chronic liver diseases and their progression to HCC. These strategies include nutritional interventions and medications that have shown promise in preclinical models. Although prevailing approaches focus on treating chronic liver disease, leveraging a wider range of interventions represents a promising area to safeguard at-risk populations. In this Review, we explore existing evidence for preventive strategies by highlighting established and potential paths to reducing HCC risk effectively and safely, especially in individuals with chronic liver diseases. We categorize the preventive strategies by the mechanism of action, including anti-inflammatory, antihyperglycaemic, lipid-lowering, nutrition and dietary, antiviral, and antifibrotic pathways. For each category, we discuss the efficacy and safety information derived from mechanistic, translational, observational and clinical trial data, pinpointing knowledge gaps and directions for future research.

Thiazolidinedione derivatives: emerging role in cancer therapy

Cancer remains the leading cause of death worldwide, with the Globocan 2022 study reporting an estimated 9.7 million cancer deaths. Without the selectivity built for tumour cells, chemotherapeutic agents could be toxic to non-cancerous cells. Administration of such non-selective cytotoxic compounds causes severe side effects and could lead to death. Improved cancer treatments are required to overcome the limitations of the current cancer treatment. The potential of thiazolidinedione derivatives as anticancer drugs has recently drawn attention, despite their primary use as insulin sensitizers in the treatment of type 2 diabetes. The ability of thiazolidinedione derivatives to alter important molecular pathways implicated in carcinogenesis, such as cell proliferation, apoptosis, angiogenesis, Raf kinase, EGFR and HER-2 kinases, HDAC, COX-2 enzyme and metastasis, is highlighted in this review, which examines the growing relevance of these compounds in cancer treatment. Thiazolidinediones have anti-inflammatory, antioxidant, and antiproliferative properties in a variety of cancer types, including breast, colon, and prostate cancers, via activating the peroxisome proliferator-activated gamma receptor (PPARγ). In addition to examining the safety profile and difficulties in clinical translation, the paper looks at preclinical and clinical research that points to these medicines potential to improve the effectiveness of immunotherapy and chemotherapy. This review highlights the encouraging therapeutic possibilities and structure-activity relationship insight of TZDs for their anticancer activity and highlights the molecular level facets of the 'glitazone' pharmacophore for its anticancer activity.

Repurposing of Metabolic Drugs Metformin and Simvastatin as an Emerging Class of Cancer Therapeutics

Metabolic alterations are commonly associated with various cancers and are recognized as contributing factors to cancer progression, invasion, and metastasis. Drug repurposing, a strategy in drug discovery, utilizes existing knowledge to recommend established drugs for new indications based on clinical data or biological evidence. This approach is considered a less risky alternative to traditional drug development. Metformin, a biguanide, is a product of Galega officinalis (French lilac) primarily prescribed for managing type 2 diabetes, is recognized for its ability to reduce hepatic glucose production and enhance insulin sensitivity, particularly in peripheral tissues such as muscle. It also improves glucose uptake and utilization while decreasing intestinal glucose absorption. Statins, first isolated from the fungus Penicillium citrinum is another class of medication mainly used to lower cholesterol levels in individuals at risk for cardiovascular diseases, work by inhibiting the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, which is essential for cholesterol biosynthesis in the liver. Metformin is frequently used in conjunction with statins to investigate their potential synergistic effects. Combination of metformin and simvastatin has gathered much attention in cancer research because of its potential advantages for cancer prevention and treatment. In this review, we analyze the effects of metformin and simvastatin, both individually and in combination, on key cancer hallmarks, and how this combination affects the expression of biomolecules and associated signaling pathways. We also summarize preclinical research, including clinical trials, on the efficacy, safety, and potential applications of repurposing metformin and simvastatin for cancer therapy.

The Role of Type 2 Diabetes Mellitus-Related Risk Factors and Drugs in Hepatocellular Carcinoma

With changes in modern lifestyles, type 2 diabetes mellitus (T2DM) has become a global epidemic metabolic disease, and hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. T2DM is a complex metabolic disorder and has been considered an independent risk factor for HCC. Growing evidence supports that T2DM-related risk factors facilitate hepatocarcinogenesis via abundant mechanisms. With the wide implementation of microbiomics, transcriptomics, and immunotherapy, the understanding of the complex mechanisms of intestinal flora and immune cell subsets have advanced tremendously in T2DM-related HCC, uncovering new findings in T2DM-related HCC patients. In addition, reports have indicated the different effects of anti-DM drugs on the progression of HCC. In this review, we summarize the effects of major T2DM-related risk factors (including hyperglycemia, hyperinsulinemia, insulin, chronic inflammation, obesity, nonalcoholic fatty liver disease, gut microbiota and immunomodulation), and anti-DM drugs on the carcinogensis and progression of HCC, as well as their potential molecular mechanisms. In addition, other factors (miRNAs, genes, and lifestyle) related to T2DM-related HCC are discussed. We propose a refined concept by which T2DM-related risk factors and anti-DM drugs contribute to HCC and discuss research directions prompted by such evidence worth pursuing in the coming years. Finally, we put forward novel therapeutic approaches to improve the prognosis of T2DM-related HCC, including exploiting novel diagnostic biomarkers, combination therapy with immunocheckpoint inhibitors, and enhancement of the standardized management of T2DM patients.

Challenges in Pharmacological Intervention in Perilipins (PLINs) to Modulate Lipid Droplet Dynamics in Obesity and Cancer

Perilipins (PLINs) are the most abundant proteins in lipid droplets (LD). These LD-associated proteins are responsible for upgrading LD from inert lipid storage structures to fully functional organelles, fundamentally integrated in the lipid metabolism. There are five distinct perilipins (PLIN1-5), each with specific expression patterns and metabolic activation, but all capable of regulating the activity of lipases on LD. This plurality creates a complex orchestrated mechanism that is directly related to the healthy balance between lipogenesis and lipolysis. Given the essential role of PLINs in the modulation of the lipid metabolism, these proteins can become interesting targets for the treatment of lipid-associated diseases. Since reprogrammed lipid metabolism is a recognized cancer hallmark, and obesity is a known risk factor for cancer and other comorbidities, the modulation of PLINs could either improve existing treatments or create new opportunities for the treatment of these diseases. Even though PLINs have not been, so far, directly considered for pharmacological interventions, there are many established drugs that can modulate PLINs activity. Therefore, the aim of this study is to assess the involvement of PLINs in diseases related to lipid metabolism dysregulation and whether PLINs can be viewed as potential therapeutic targets for cancer and obesity.

Lipid metabolism reprogramming of CD8+ T cell and therapeutic implications in cancer

Effector, memory and exhaustion are three phenotypes of CD8⁺ T cell. In tumor microenvironment (TME), metabolism dysfunction of the three should take the blame for immune escape. Against background of CD8⁺ T cell in normal development, multiple determinants in TME, including nutrition competition, PD-1 signals and other cancer- CD8⁺ T cell interaction, cause metabolism reprograming, including failure in energy metabolism and other abnormal lipid metabolism. Further, incompatibility of different CD8⁺ T cell metabolism pattern results in unresponsiveness of immune checkpoint blockade (ICB). Therefore, combination of ICB and drugs aiming at abnormal lipid metabolism provides promising direction to improve cancer therapy.

The crucial role and mechanism of insulin resistance in metabolic disease

Insulin resistance (IR) plays a crucial role in the development and progression of metabolism-related diseases such as diabetes, hypertension, tumors, and nonalcoholic fatty liver disease, and provides the basis for a common understanding of these chronic diseases. In this study, we provide a systematic review of the causes, mechanisms, and treatments of IR. The pathogenesis of IR depends on genetics, obesity, age, disease, and drug effects. Mechanistically, any factor leading to abnormalities in the insulin signaling pathway leads to the development of IR in the host, including insulin receptor abnormalities, disturbances in the internal environment (regarding inflammation, hypoxia, lipotoxicity, and immunity), metabolic function of the liver and organelles, and other abnormalities. The available therapeutic strategies for IR are mainly exercise and dietary habit improvement, and chemotherapy based on biguanides and glucagon-like peptide-1, and traditional Chinese medicine treatments (e.g., herbs and acupuncture) can also be helpful. Based on the current understanding of IR mechanisms, there are still some vacancies to follow up and consider, and there is also a need to define more precise biomarkers for different chronic diseases and lifestyle interventions, and to explore natural or synthetic drugs targeting IR treatment. This could enable the treatment of patients with multiple combined metabolic diseases, with the aim of treating the disease holistically to reduce healthcare expenditures and to improve the quality of life of patients to some extent.

Role of adipocytokines in endometrial cancer progression

Endometrial cancer is considered a significant barrier to increasing life expectancy and remains one of the most common malignant cancers among women in many countries worldwide. The increasing mortality rates are potentially proportional to the increasing obesity incidence. Adipose tissue secretes numerous adipocytokines, which may play important roles in endometrial cancer progression. In this scenario, we describe the role of adipocytokines in cell proliferation, cell invasion, cell adhesion, inflammation, angiogenesis, and anti-apoptotic action. A better understanding of the mechanisms of these adipocytokines may open up new therapeutic avenues for women with endometrial cancer. In the future, larger prospective studies focusing on adipocytokines and specific inhibitors should be directed at preventing the rapidly increasing prevalence of gynecological malignancies.

A Scoping Review of the Use of Pioglitazone in the Treatment of Temporo-Mandibular Joint Arthritis

Thiazolidinediones (TZDs) are a group of diabetes medications currently being investigated for anti-arthritis effectiveness, one of which is pioglitazone. The purpose of this scoping review is to evaluate the potential use of pioglitazone in the treatment of temporomandibular joint (TMJ) arthritis. The criteria of eligibility were studies with the diagnosis of arthritis and pioglitazone treatment with a change in any inflammation index as an outcome. Of the 1169 records initially identified following the selection process, two animal studies and four clinical studies were included in the review. Improvements from the baseline were observed in each treatment group for each inflammation indicator. The results of the animal studies on the temporomandibular joints and on patients with rheumatoid and psoriatic arthritis indicate that the drug in question may have potential to treat arthritis, including within the temporomandibular joint.

Bauhinia forficata link extract attenuates insulin resistance by preserving glucose uptake in gastrocnemius muscle

Bioactive metabolites from Bauhinia forficata Link (Bf extract) hold therapeutic potential for type 2 diabetes mellitus (T2DM) but the mechanism remains poorly understood. This study aimed to test the extract from Bf leaves obtained by decoction on the prevention of T2DM in vivo. The Bf extract was tested on a streptozotocin-induced T2DM mouse model fed on a high-fat diet. The insulin resistance was attenuated in T2DM animals supplemented with Bf extract, which indicates glucose intolerance reduction and p-AKT/AKT ratio preservation in the gastrocnemius muscle. These observations suggested that Bf extract enhanced glucose uptake. Nevertheless, there was no preservation in β-cell insulin secretion in Bf extract-treated T2DM mice. Interestingly, the Bf extract reduced body weight gain without affecting total energy intake. Hence, Bf extract has a hypoglycemic effect which could attenuate the development of insulin resistance.

PPAR-γ Modulators as Current and Potential Cancer Treatments

Worldwide, cancer has become one of the leading causes of mortality. Peroxisome Proliferator-Activated Receptors (PPARs) is a family of critical sensors of lipids as well as regulators of diverse metabolic pathways. They are also equipped with the capability to promote eNOS activation, regulate immunity and inflammation response. Aside from the established properties, emerging discoveries are also made in PPAR's functions in the cancer field. All considerations are given, there exists great potential in PPAR modulators which may hold in the management of cancers. In particular, PPAR-γ, the most expressed subtype in adipose tissues with two isoforms of different tissue distribution, has been proven to be able to inhibit cell proliferation, induce cell cycle termination and apoptosis of multiple cancer cells, promote intercellular adhesion, and cripple the inflamed state of tumor microenvironment, both on transcriptional and protein level. However, despite the multi-functionalities, the safety of PPAR-γ modulators is still of clinical concern in terms of dosage, drug interactions, cancer types and stages, etc. This review aims to consolidate the functions of PPAR-γ, the current and potential applications of PPAR-γ modulators, and the challenges in applying PPAR-γ modulators to cancer treatment, in both laboratory and clinical settings. We sincerely hope to provide a comprehensive perspective on the prospect of PPAR-γ applicability in the field of cancer treatment.

Relationships are between metformin use and survival in pancreatic cancer patients concurrent with diabetes: A systematic review and meta-analysis

BACKGROUND

Increased risk and cancer-related mortality is observed in pancreatic cancer (PC) patients with diabetes mellitus (DM). Whether using metformin as glucose-lowering therapy can result in survival benefit in this group of patients is still unclear.

METHODS

A meta-analysis of 21 studies that including 38,772 patients was performed to investigate the association between metformin and overall survival in patients with PC and concurrent DM.

RESULTS

A significant survival benefit was observed in metformin treatment group compared with non-metformin group (hazard ratio [HR] = 0.83, 95% confidence interval [CI]: 0.74-0.91). These associations were observed in both subgroups of Asian countries (HR = 0.69, 95% CI: 0.60-0.79) and Western countries (HR = 0.86, 95% CI: 0.76-0.95), the former was more obvious. Survival benefit was gained for patients at early stage (HR = 0.75, 95% CI: 0.64-0.85) and mixed stage (HR = 0.81, 95% CI: 0.70-0.91), but not for patients at advanced stage (HR = 0.99, 95% CI: 0.74-1.24). Similarly, survival benefit was also observed in patients receiving surgery (HR = 0.82, 95% CI: 0.69-0.94) and comprehensive treatment (HR = 0.85, 95% CI: 0.77-0.93), but not in chemotherapy group (HR = 0.99, 95% CI: 0.67-1.30). No obvious benefit was suggested when pooled by time-varying COX model (HR = 0.94, 95% CI: 0.86-1.03).

CONCLUSIONS

These results suggest that metformin is associated with survival benefit in patients with PC and concurrent DM. Further randomized controlled trials and prospective studies with larger sample sizes are required to confirm our findings.

Oxidative Stress Management in Chronic Liver Diseases and Hepatocellular Carcinoma

Chronic viral hepatitis B and C and non-alcoholic fatty liver disease (NAFLD) have been widely acknowledged to be the leading causes of liver cirrhosis and hepatocellular carcinoma. As anti-viral treatment progresses, the impact of NAFLD is increasing. NAFLD can coexist with chronic viral hepatitis and exacerbate its progression. Oxidative stress has been recognized as a chronic liver disease progression-related and cancer-initiating stress response. However, there are still many unresolved issues concerning oxidative stress, such as the correlation between the natural history of the disease and promising treatment protocols. Recent findings indicate that oxidative stress is also an anti-cancer response that is necessary to kill cancer cells. Oxidative stress might therefore be a cancer-initiating response that should be down regulated in the pre-cancerous stage in patients with risk factors for cancer, while it is an anti-cancer cell response that should not be down regulated in the post-cancerous stage, especially in patients using anti-cancer agents. Antioxidant nutrients should be administered carefully according to the patients’ disease status. In this review, we will highlight these paradoxical effects of oxidative stress in chronic liver diseases, pre- and post-carcinogenesis.