The effects of salsalate on glycemic control in patients with type 2 diabetes: a randomized trial

Inflammatory Trajectory of Type 2 Diabetes: Novel Opportunities for Early and Late Treatment

Low-grade inflammation (LGI) represents a key driver of type 2 diabetes (T2D) and its associated cardiovascular diseases (CVDs). Indeed, inflammatory markers such as hs-CRP and IL-6 predict the development of T2D and its complications, suggesting that LGI already increases before T2D diagnosis and remains elevated even after treatment. Overnutrition, unhealthy diets, physical inactivity, obesity, and aging are all recognized triggers of LGI, promoting insulin resistance and sustaining the pathogenesis of T2D. Once developed, and even before frank appearance, people with T2D undergo a pathological metabolic remodeling, with an alteration of multiple CVD risk factors, i.e., glycemia, lipids, blood pressure, and renal function. In turn, such variables foster a range of inflammatory pathways and mechanisms, e.g., immune cell stimulation, the accrual of senescent cells, long-lasting epigenetic changes, and trained immunity, which are held to chronically fuel LGI at the systemic and tissue levels. Targeting of CVD risk factors partially ameliorates LGI. However, some long-lasting inflammatory pathways are unaffected by common therapies, and LGI burden is still increased in many T2D patients, a phenomenon possibly underlying the residual inflammatory risk (i.e., having hs-CRP > 2 mg/dL despite optimal LDL cholesterol control). On the other hand, selected disease-modifying drugs, e.g., GLP-1RA, seem to also act on the pathogenesis of T2D, curbing the inflammatory trajectory of the disease and possibly preventing it if introduced early. In addition, selected trials demonstrated the potential of canonical anti-inflammatory therapies in reducing the rate of CVDs in patients with this condition or at high risk for it, many of whom had T2D. Since colchicine, an inhibitor of immune cell activation, is now approved for the prevention of CVDs, it might be worth exploring a possible therapeutic paradigm to identify subjects with T2D and an increased LGI burden to treat them with this drug. Upcoming studies will reveal whether disease-modifying drugs reverse early T2D by suppressing sources of LGI and whether colchicine has a broad benefit in people with this condition.

Safety and Efficacy of Canakinumab for the Prevention and Control of Type 2 Diabetes Mellitus and Its Complications: A Systematic Review

Today, diabetes mellitus (DM) is one of the leading causes of morbidity and mortality globally.In this grim context, while our current armamentarium of anti-diabetic agents is vast and increasingly available, glycemic control in a significant proportion of these patients continues to remain sub-optimal.This necessitates the exploration of other potential cellular pathways and targets to effectively manage this notorious disease and its numerous complications. Inflammatory responses are thought to be implicated in the decline of pancreatic beta-cell function, with interleukin-1 beta (IL-1β) playing an important role in these pathways. Canakinumab, a human monoclonal anti-IL-1β antibody, operates by reducing inflammation, potentially safeguarding or enhancing pancreatic beta-cell function. This systematic review aims to study the safety and efficacy of canakinumab in the prevention and control of type 2 diabetes mellitus (T2DM) and its complications. This study was conducted in accordance with the PRISMA 2020 Guidelines. PubMed including MEDLINE, Google Scholar and Cochrane Library were used as information sources and randomized clinical trials and retrospective observational studies evaluating patients with T2DM or impaired glucose tolerance with/without complications receiving canakinumab, compared with placebo or standard therapy and reporting about glycemic indicators including hemoglobin A1C (HbA1C) or blood sugar levels (BSL) or insulin levels and/or inflammatory indicators including high-sensitivity C-reactive protein (hsCRP) or interleukin-6 (IL-6) were included. Non-randomized clinical trials, animal studies, review articles, case reports, case series, studies not in the English language and those evaluating type 1 DM were excluded. In total, 271 studies were identified to be included in this study. Subsequently, 27 were found to be duplicate records and were eliminated. Manual screening of title/abstract of 244 records was done which found 207 to be ineligible and 37 studies were shortlisted. These were retrieved and full-text screening was undertaken which resulted in the exclusion of 28 reports due to the following reasons: ineligible study design (17), studies evaluating type 1 DM (three), studies evaluating anakinra (one), trial being canceled (three) and duplicate studies (four). Subsequently, a total of nine studies were included in the final review. All studies were included post quality appraisal. We found that canakinumab had a modest but mostly non-significant effect on glycemic parameters including HbA1C, while having a consistently significant reduction in systemic inflammatory parameters like hsCRP and IL-6. Additionally, it was found to have a significant reduction in incident major adverse cardiovascular events (MACE). Canakinumab was also found to be safe and well-tolerated in all patient populations. Although canakinumab did not reduce incident T2DM, an exploration of alternative pathways and targets implicated in the pathogenesis of this disease process is warranted for the prevention and control of T2DM.

Salsalate Improves Postprandial Glycemic and Some Lipid Responses in Persons With Tetraplegia: A Randomized Clinical Pilot Trial With Crossover Design

Objectives

To investigate the effects of salsalate on fasting and postprandial (PP) glycemic, lipidemic, and inflammatory responses in persons with tetraplegia.

Methods

This study was a randomized, double-blind, cross-over design. It was conducted at a university laboratory. Ten males aged 25 to 50 years with SCI at C5-8 levels for ≥1 year underwent 1 month of placebo and salsalate (4 g/day) treatment. Blood samples were drawn before and 4 hours after breakfast and lunch fast-food meal consumption.

Results

Descriptive statistics indicate that fasting and PP glucose values were reduced with salsalate (pre-post mean difference, 4 ± 5 mg/dL and 8 ± 8 mg/dL, respectively) but largely unchanged with placebo (0 ± 6 mg/dL and -0 ± 7 mg/dL, respectively). Insulin responses were generally reciprocal to glucose, however less pronounced. Fasting free fatty acids were significantly reduced with salsalate (191 ± 216 mg/dL, p = .021) but not placebo (-46 ± 116 mg/dL, p = .878). Results for triglycerides were similar (25 ± 34 mg/dL, p =.045, and 7 ± 29 mg/dL, p = .464). Fasting low-density lipoprotein (LDL) levels were higher after salsalate (-10 ± 12 mg/dL, p = .025) but not placebo (2 ± 9 mg/dL, p = .403) treatment. Inflammatory markers were largely unchanged.

Conclusion

In this pilot trial, descriptive values indicate that salsalate decreased fasting and PP glucose response to fast-food meal challenge at regular intervals in persons with tetraplegia. Positive effects were also seen for some lipid but not for inflammatory response markers. Given the relatively "healthy" metabolic profiles of the participants, it is possible that salsalate's effects may be greater and more consistent in people with less favorable metabolic milieus.

The PTGS2/COX2-PGE2 signaling cascade in inflammation: Pro or anti? A case study with type 1 diabetes mellitus

Prostaglandins are lipid mediators involved in physiological processes, such as constriction or dilation of blood vessels, but also pathophysiological processes, which include inflammation, pain and fever. They are produced by almost all cell types in the organism by activation of Prostaglandin endoperoxide synthases/Cyclooxygenases. The inducible Prostaglandin Endoperoxide Synthase 2/Cyclooxygenase 2 (PTGS2/COX2) plays an important role in pathologies associated with inflammatory signaling. The main product derived from PTGS2/COX2 expression and activation is Prostaglandin E2 (PGE2), which promotes a wide variety of tissue-specific effects, pending environmental inputs. One of the major sources of PGE2 are infiltrating inflammatory cells - the production of this molecule increases drastically in damaged tissues. Immune infiltration is a hallmark of type 1 diabetes mellitus, a multifactorial disease that leads to autoimmune-mediated pancreatic beta cell destruction. Controversial effects for the PTGS2/COX2-PGE2 signaling cascade in pancreatic islet cells subjected to diabetogenic conditions have been reported, allocating PGE2 as both, cause and consequence of inflammation. Herein, we review the main effects of this molecular pathway in a tissue-specific manner, with a special emphasis on beta cell mass protection/destruction and its potential role in the prevention or development of T1DM. We also discuss strategies to target this pathway for future therapies.

A nitroalkene derivative of salicylate alleviates diet-induced obesity by activating creatine metabolism and non-shivering thermogenesis

Obesity-related type II diabetes (diabesity) has increased global morbidity and mortality dramatically. Previously, the ancient drug salicylate demonstrated promise for the treatment of type II diabetes, but its clinical use was precluded due to high dose requirements. In this study, we present a nitroalkene derivative of salicylate, 5-(2-nitroethenyl)salicylic acid (SANA), a molecule with unprecedented beneficial effects in diet-induced obesity (DIO). SANA reduces DIO, liver steatosis and insulin resistance at doses up to 40 times lower than salicylate. Mechanistically, SANA stimulated mitochondrial respiration and increased creatine-dependent energy expenditure in adipose tissue. Indeed, depletion of creatine resulted in the loss of SANA action. Moreover, we found that SANA binds to creatine kinases CKMT1/2, and downregulation CKMT1 interferes with the effect of SANA in vivo. Together, these data demonstrate that SANA is a first-in-class activator of creatine-dependent energy expenditure and thermogenesis in adipose tissue and emerges as a candidate for the treatment of diabesity.

The rheumatoid arthritis drug auranofin lowers leptin levels and exerts antidiabetic effects in obese mice

Low-grade, sustained inflammation in white adipose tissue (WAT) characterizes obesity and coincides with type 2 diabetes mellitus (T2DM). However, pharmacological targeting of inflammation lacks durable therapeutic effects in insulin-resistant conditions. Through a computational screen, we discovered that the FDA-approved rheumatoid arthritis drug auranofin improved insulin sensitivity and normalized obesity-associated abnormalities, including hepatic steatosis and hyperinsulinemia in mouse models of T2DM. We also discovered that auranofin accumulation in WAT depleted inflammatory responses to a high-fat diet without altering body composition in obese wild-type mice. Surprisingly, elevated leptin levels and blunted beta-adrenergic receptor activity achieved by leptin receptor deletion abolished the antidiabetic effects of auranofin. These experiments also revealed that the metabolic benefits of leptin reduction were superior to immune impacts of auranofin in WAT. Our studies uncover important metabolic properties of anti-inflammatory treatments and contribute to the notion that leptin reduction in the periphery can be accomplished to treat obesity and T2DM.

Immunometabolism in type 2 diabetes mellitus: tissue-specific interactions

The immune system is frequently described in the context of its protective function against infections and its role in the development of autoimmunity. For more than a decade, the interactions between the immune system and metabolic processes have been reported, in effect creating a new research field, termed immunometabolism. Accumulating evidence supports the hypothesis that the development of metabolic diseases may be linked to inflammation, and reflects, in some cases, the activation of immune responses. As such, immunometabolism is defined by 1) inflammation as a driver of disease development and/or 2) metabolic processes stimulating cellular differentiation of the immune components. In this review, the main factors capable of altering the immuno-metabolic communication leading to the development and establishment of obesity and diabetes are comprehensively presented. Tissue-specific immune responses suggested to impair metabolic processes are described, with an emphasis on the adipose tissue, gut, muscle, liver, and pancreas.

Evidence that periodontal treatment improves diabetes outcomes: a systematic review and meta-analysis

CONTEXT

The effect of periodontal therapy on diabetes outcomes has not been established.

OBJECTIVE

This update examines the effect of periodontal treatment on diabetes outcomes.

DATA SOURCES

Literature since October 2009 using MEDLINE.

STUDY ELIGIBILITY CRITERIA

Published RCTs including periodontal therapy for diabetic subjects, a metabolic outcome, an untreated control group, and follow-up of 3 months.

DATA EXTRACTION

Pre-defined data fields, including study quality indicators were used.

DATA SYNTHESIS

A search revealed 56 publications of which 9 met inclusion criteria. Mean change of HbA1c from baseline was compared across treatment groups. Pooled analysis was based on random effects models.

RESULTS

A meta-analysis indicated a mean treatment effect of -0.36% HbA1c (CI -0.54, -0.19) compared to no treatment after periodontal therapy (p < 0.0001). Heterogeneity tests revealed only minimal evidence of publication bias (I(2 ) = 9%).

LIMITATIONS

Small sample size and high risk of bias remain problematic for studies of this type. Periodontal therapy varied considerably.

CONCLUSION

The modest reduction in HbA1c observed as a result of periodontal therapy in subjects with type 2 diabetes is consistent with previous systematic reviews. Despite this finding, there is limited confidence in the conclusion due to a lack of multi-centre trials of sufficient sample size are lacking.

AMPK activation--protean potential for boosting healthspan

AMP-activated kinase (AMPK) is activated when the cellular (AMP+ADP)/ATP ratio rises; it therefore serves as a detector of cellular "fuel deficiency." AMPK activation is suspected to mediate some of the health-protective effects of long-term calorie restriction. Several drugs and nutraceuticals which slightly and safely impede the efficiency of mitochondrial ATP generation-most notably metformin and berberine-can be employed as clinical AMPK activators and, hence, may have potential as calorie restriction mimetics for extending healthspan. Indeed, current evidence indicates that AMPK activators may reduce risk for atherosclerosis, heart attack, and stroke; help to prevent ventricular hypertrophy and manage congestive failure; ameliorate metabolic syndrome, reduce risk for type 2 diabetes, and aid glycemic control in diabetics; reduce risk for weight gain; decrease risk for a number of common cancers while improving prognosis in cancer therapy; decrease risk for dementia and possibly other neurodegenerative disorders; help to preserve the proper structure of bone and cartilage; and possibly aid in the prevention and control of autoimmunity. While metformin and berberine appear to have the greatest utility as clinical AMPK activators-as reflected by their efficacy in diabetes management-regular ingestion of vinegar, as well as moderate alcohol consumption, may also achieve a modest degree of health-protective AMPK activation. The activation of AMPK achievable with any of these measures may be potentiated by clinical doses of the drug salicylate, which can bind to AMPK and activate it allosterically.

The effect of salsalate on biochemical factors and endothelial dysfunction of prediabetic patients: A randomized clinical trial

BACKGROUND

The beneficial effect of using nonacetylated salicylates such as salsalate on decreasing the speed of diabetes progression is a controversial issue. The aim of this study was to evaluate the effect of salsalate on metabolic-syndrome-associated parameters as well as the endothelial function of diabetic and impaired glucose tolerance patients.

MATERIALS AND METHODS

Patients were collected from Isfahan endocrinology research center referrals. Patients with impaired glucose tolerance diagnosis or newly diagnosed diabetes were enrolled in the study. Patients were randomized to receive 1.5 g salsalate (2 × 750 mg) BID or placebo twice a day for 3 months. After the mentioned period, all patients were recalled and complete examination was done; blood samples for biochemistry measurements were drawn (for measuring FBS, post prandial glucose, HbA1C, Total cholesterol, HDL, TG, LDL) and forearm flow-mediated dilation (FMD) was performed.

RESULTS

Forty patients were enrolled, 32 patients (80%) were female. Mean age of patients was 47.15 ± 6.67 years. FBS (fasting blood sugar) was shown to be significantly different between intervention and control subjects before or after treatment. FMD increased significantly in the intervention group (P = 0.004).

CONCLUSION

The study showed that salsalate decreased FBS levels of patients. It may also improve endothelial function as FMD increased significantly in the intervention group.

Targeting adipose tissue inflammation to treat the underlying basis of the metabolic complications of obesity

The prevalence of obesity has increased throughout the last three decades due to genetic, metabolic, behavioral, and environmental factors [1]. Obesity in turn increases risk for a number of metabolic diseases including type 2 diabetes, cardiovascular disease, fatty liver disease and some forms of cancer [1]. Despite the well-known link between obesity and increased morbidity, the mechanism of this remains elusive. Thus, the question 'why does increased body fat cause increased metabolic comorbidities' remains unanswered. By understanding the underlying basis of obesity-associated metabolic diseases, different therapies could be designed to target relevant pathways. Although we lack a full understanding of the underlying mechanisms that result in disease, several putative explanations exist for why fat affects metabolic health. One such theory is based on the anatomic location of fat deposition and ectopic fat accumulation [2]. Specifically, current literature suggests that visceral, liver and skeletal fat accumulation affects organ function and contributes to the development of insulin resistance, fatty liver, and the metabolic syndrome [3]. However, even in individuals matched for body fat and fat distribution, significant differences can exist in metabolic outcomes, and the phenomenon of metabolically healthy obese has been well described [4]. More recent data suggest the alternative hypothesis relating excess adipose tissue to disease risk based on the metabolic function and morphological properties of adipose tissue. In this scenario, excess adipose tissue is hypothesized to contribute to a state of chronic inflammation which promotes development of insulin resistance as well as other metabolic complications by stimulating nuclear factor-ĸB and Jun N-terminal kinase pathways in adipocytes and the liver [5]. In this paper, we will review the hypothesis linking excess adipose tissue to increased disease risk through adipose tissue inflammation.