Pharmacogenomics and pharmacogenetics of thiazolidinediones: role in diabetes and cardiovascular risk factors

Optimizing the Adipogenic Induction Protocol Using Rosiglitazone Improves the Physiological Parameters and Differentiation Capacity of Adipose Tissue-Derived Mesenchymal Stem Cells for Horses, Sheep, Dogs, Murines, and Humans

The investigation of adipose tissue-derived mesenchymal stem cells (ASCs) has received considerable interest in regenerative medicine. A nontoxic adipogenic induction protocol valid for cells of different mammalian species has not been described. This study aims to establish an adipogenic differentiation protocol suitable for horses, sheep, dogs, murines, and human cells. An optimized rosiglitazone protocol, consisting of 5% fetal calf serum in Dulbecco's Modified Eagle's Medium, 10 μg/mL insulin, 0.55 μg/mL transferrin, 6.8 ng sodium selenite, 1 μM dexamethasone, and 1-5 μM of rosiglitazone, is compared to the 3-isobutyl-1-methylxantine (IBMX) protocol, where rosiglitazone was replaced with 0.5 mM IBMX and 0.2 mM indomethacin. Cell viability, cytotoxicity, a morphometric analysis of the lipid, and the expression of adipogenic markers for 14 days were assessed. The data revealed that using 5 µM of rosiglitazone promotes the adipogenic differentiation capacity in horse, sheep, and dog cells compared to IBMX induction. Meanwhile, marked reductions in the cell viability and cell number with the IBMX protocol were detected, and rosiglitazone increased the cell number and lipid droplet size, prevented apoptosis, and upregulated FABP-4 and Leptin expression in the cells of most of the species. Our data revealed that the rosiglitazone protocol improves the adipogenesis of ASCs, together with having less toxicity, and should be considered for cell reproducibility and clinical applications targeting obesity.

Beyond Blood Sugar: Investigating the Cardiovascular Effects of Antidiabetic Drugs

Cardiovascular disease is a major comorbidity associated with diabetes mellitus. Various antidiabetic drugs are currently used to treat type 2 diabetes mellitus and have varying effects on the cardiovascular system. Some drugs, such as glucagon-like peptide 1 (GLP-1) agonists and sodium-glucose cotransporter 2 (SGLT-2) inhibitors, are cardioprotective, whereas others, such as insulin, have deleterious effects on the cardiovascular system. This narrative review assessed the impact of antidiabetic drugs on cardiovascular health in the management of diabetes mellitus. It critically examines various classes of these medications, including conventional options such as metformin and newer agents such as incretin-based therapies and SGLT-2.

Effect of PPARγ on oxidative stress in diabetes-related dry eye

Oxidative stress is closely associated with diabetes and can cause free radical accumulation and eventually lead to ocular surface tissue damage. The purpose of this study was to investigate peroxisome proliferator-activated receptor-γ (PPARγ) expression in the lacrimal gland (LG), meibomian gland, and cornea of diabetes-related dry eye mice and whether the PPARγ agonist rosiglitazone can alleviate the oxidative stress of the ocular surface, thereby improving the condition of diabetes-related dry eye. Quantitative RT-PCR (Q-PCR) showed that the PPARγ, catalase, glutathione peroxidase 3, and heme oxygenase-1 (HO-1) mRNA expression levels in the LG of diabetes-related dry eye mice decreased at 8 and 12 weeks. In addition, the increased levels of oxidative stress were confirmed by western blot. Although the mRNA expression levels of antioxidant enzymes in the cornea and meibomian gland decreased at 8 weeks, some of them recovered by 12 weeks. Rosiglitazone alleviated ocular surface damage and increased corneal sensitivity and tear production in diabetes-related dry eye mice. Moreover, the reactive oxygen species accumulation was reduced and the PPARγ, HO-1, and glutathione peroxidase 3 mRNA expression levels were increased in the LG. The PPARγ, HO-1, translocase of the outer membrane 20, and mitochondrial transcription factor A protein levels were also significantly increased. These results demonstrated that rosiglitazone reduced oxidative stress in the LG of diabetes-related dry eye mice, at least in part, by activating PPARγ to up-regulate antioxidant enzyme expression.

Treatment of type 2 diabetes patients with heart conditions

INTRODUCTION

While type 2 diabetes mellitus (T2DM) increases the risk of cardiac complications, diabetes treatment choices may increase or decrease the rates of cardiac events. In the present review, we comprehensively discussed the treatment options of diabetic subjects with cardiac conditions.

AREAS COVERED

Current evidence related to diabetes treatment in cardiac situations has been reviewed. Clinical trials and meta-analyses on cardiac safety of anti-diabetic medicines are discussed. Treatment choices with proven benefits and those at least without associated increased cardiac risk were drawn from clinical trials; meta-analyses and cardiac safety studies in the recent medical literature were the basis of the suggestions in the present review.

EXPERT OPINION

We can suggest that hypoglycemia and extreme hyperglycemia should be avoided in acute ischemic heart conditions. Certain diabetic treatment options, especially sodium-glucose cotransporter-2 (SGLT2) inhibitors, can reduce overall cardiovascular mortality and hospitalization due to heart failure. Therefore, we suggest that physicians should choose SGLT2 inhibitors as the first-line treatment option in diabetic patients with heart failure or those who have a high risk of heart failure development. T2DM increases the risk of atrial fibrillation (AF), and metformin and pioglitazone seem to reduce the risk of AF in diabetic population.

A Practical Review of Diabetes Mellitus Type 2 Treatment in Primary Care

The treatment of diabetes mellitus type 2 (DM2) is becoming more complex as new medications are approved. Primary care providers must maintain their medical knowledge on emerging medications for best patient care. This review simplifies the non-insulin treatments of diabetes with an emphasis on the cardio-renal protectants, sodium-glucose cotransporter 2 (SGLT-2) inhibitors and glucagon-like peptide 1 receptor agonists (GLP-1).

Thiazolidinediones, alpha-glucosidase inhibitors, meglitinides, sulfonylureas, and hepatocellular carcinoma risk: A meta-analysis

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related death worldwide. Effects of second-line oral antidiabetic medications on incident HCC risk in individuals with type 2 diabetes mellitus remain unclear. This study evaluated associations between sulfonylureas, thiazolidinediones, meglitinides and alpha-glucosidase inhibitors, and incident HCC risk.

METHODS

We systematically reviewed all studies on PubMed, Embase and Web of Science databases. Studies were included if they documented: (1) exposure to oral antidiabetic medication classes; (2) HCC incidence; (3) relative risks/odds ratios (OR) for HCC incidence. Eight eligible observational studies were identified. We performed random-effects meta-analyses to calculate pooled adjusted ORs (aORs) and 95% confidence intervals (CI).

RESULTS

Thiazolidinedione use (7 studies, 280,567 participants, 19,242 HCC cases) was associated with reduced HCC risk (aOR = 0.92, 95% CI = 0.86-0.97, I² = 43%), including among Asian subjects (aOR = 0.90, 95% CI = 0.83-0.97), but not Western subjects (aOR = 0.95, 95% CI = 0.87-1.04). Alpha-glucosidase inhibitor use (3 studies, 56,791 participants, 11,069 HCC cases) was associated with increased HCC incidence (aOR = 1.08; 95% CI = 1.02-1.14, I² = 21%). Sulfonylurea use (8 studies, 281,180 participants, 19,466 HCC cases) was associated with increased HCC risk in studies including patients with established liver disease (aOR = 1.06, 95% CI = 1.02-1.11, I² = 75%). Meglitinide use (4 studies, 58,237 participants, 11,310 HCC cases) was not associated with HCC incidence (aOR = 1.19; 95% CI = 0.89-1.60, I² = 72%).

CONCLUSIONS

Thiazolidinedione use was associated with reduced HCC incidence in Asian individuals with diabetes. Alpha-glucosidase inhibitor or sulfonylurea use was associated with modestly increased HCC risk; future research should determine whether those agents should be avoided in patients with chronic liver disease.

An Artificial-Intelligence-Discovered Functional Ingredient, NRT_N0G5IJ, Derived from Pisum sativum, Decreases HbA1c in a Prediabetic Population

The prevalence of prediabetes is rapidly increasing, and this can lead to an increased risk for individuals to develop type 2 diabetes and associated diseases. Therefore, it is necessary to develop nutritional strategies to maintain healthy glucose levels and prevent glucose metabolism dysregulation in the general population. Functional ingredients offer great potential for the prevention of various health conditions, including blood glucose regulation, in a cost-effective manner. Using an artificial intelligence (AI) approach, a functional ingredient, NRT_N0G5IJ, was predicted and produced from Pisum sativum (pea) protein by hydrolysis and then validated. Treatment of human skeletal muscle cells with NRT_N0G5IJ significantly increased glucose uptake, indicating efficacy of this ingredient in vitro. When db/db diabetic mice were treated with NRT_N0G5IJ, we observed a significant reduction in glycated haemoglobin (HbA1c) levels and a concomitant benefit on fasting glucose. A pilot double-blinded, placebo controlled human trial in a population of healthy individuals with elevated HbA1c (5.6% to 6.4%) showed that HbA1c percentage was significantly reduced when NRT_N0G5IJ was supplemented in the diet over a 12-week period. Here, we provide evidence of an AI approach to discovery and demonstrate that a functional ingredient identified using this technology could be used as a supplement to maintain healthy glucose regulation.

Diabetes Management in Patients with Heart Failure

Diabetes and heart failure (HF) are common diseases, each affecting large segments of the world population. Moreover, prevalence rates for both are expected to rise dramatically over coming decades. The high prevalence rates of both diseases and wellrecognized association of diabetes as a risk factor for HF make it inevitable that both diseases co-exist in a large number of patients, complicating their management and increasing the risk of a poor outcome. Management of diabetes has been shown to impact clinical events in patients with HF and there is emerging evidence that agents used to treat diabetes can reduce HF events, even in non-diabetic patients. In this review we summarize the clinical course and treatment of patients with type 2 diabetes mellitus (T2DM) and HF and review the efficacy and safety of pharmacological agents in patients with T2DM at risk for HF and those with established disease.

Atypical Diabetes Presentations in Sub-Saharan Africa Classification Puzzle and Possible Role of Precision Medicine

Precision in the diagnosis and classification of diabetes mellitus, a complex heterogeneous disease is increasingly required to achieve treatment goals and prevent complications. Several reviews over decades have not completely solved the diabetes classification puzzle. African clinicians are sometimes confronted with the difficulty of classifying a newly diagnosed diabetes patient presenting atypically. These unusual presentations fall into those with diagnosis of either clinical type 1 or 2 diabetes but having some diagnostic and/or therapeutic features at variance with what are seen in the Western nations, those with tropical diabetes and those known as ketosis-prone type 2 diabetes (KPD). Reports from many African countries indicate that patients do not fit the classic pattern seen in the Western nations. In recent times, there has been groundswell of pressures and proposed models to evolve a more accurate classification of diabetes and the recent 2019 WHO diabetes classification seems to have acknowledged and accommodated these concerns. Perhaps advances in genomic knowledge could help with precision in diabetes classification, especially in Africa. This review seeks to highlight the challenges often encountered with classifying diabetes patients in Africa, and proffer suggestions on the way forward including possible benefit from advances in molecular genomics.

Optimizing drug therapy in frail patients with type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is closely linked with ageing. In frail diabetic patients, the risks of intensive antidiabetic therapy outweigh the potential benefits.

AIMS

To study the prevalence of T2DM in frail elderly patients, to identify inappropriate prescription (IP) of antidiabetic drugs and to study the relationship between patients' frailty index (FI) with polypharmacy and IP.

METHODS

This was a prospective, descriptive, observational study of elderly patients. Each patient's antidiabetic treatment was analysed by applying the patient-centred prescription model (PCP), which centres therapeutic decisions on the patient's global assessment and individual therapeutic goal.

RESULTS

210 patients with T2DM were included (25.15% prevalence). They were characterised by high multimorbidity and frailty. 93.3% presented polypharmacy and 51% excessive polypharmacy. IP was identified in 66.2% of patients. A statistically significant relationship was found between the progression in FI degree and IP prevalence (p < 0.05. During the admission, drug therapy regimens were modified in 97.1% of cases with IP (n = 136).

DISCUSSION

These results suggest that in clinical practice T2DM treatment is not individualised, but rather is based on the same general recommendations for the population as a whole.

CONCLUSIONS

There is a high prevalence of T2DM in the elderly. As the frailty of patients increases, so does the prevalence of IP. The application of PCP model enables drug therapy optimization in frail patients according to their main therapeutic goal, and contributes to provide clinical evidences on the applicability of a set of knowledge areas from the theoretical framework to the daily clinical practice.

Association between serum anti‑ASXL2 antibody levels and acute ischemic stroke, acute myocardial infarction, diabetes mellitus, chronic kidney disease and digestive organ cancer, and their possible association with atherosclerosis and hypertension

The aim of the present study was to identify novel antibody markers for the early diagnosis of atherosclerosis in order to improve the prognosis of patients at risk for acute ischemic stroke (AIS) and acute myocardial infarction (AMI). A first screening involved the serological identification of antigens by recombinant cDNA expression cloning and identified additional sex combs-like 2 (ASXL2) as a target antigen recognized by serum IgG antibodies in the sera of patients with atherosclerosis. Antigens, including the recombinant glutathione S-transferasefused ASXL2 protein and its synthetic peptide were then prepared to examine serum antibody levels. Amplified luminescence proximity homoge-neous assay-linked immunosorbent assay, which incorporates glutathione-donor beads and anti-human-IgG-acceptor beads, revealed significantly higher serum antibody levels against the ASXL2 protein and its peptide in the patients with AIS, diabetes mellitus, AMI, chronic kidney disease, esophageal squamous cell carcinoma, or colorectal carcinoma compared with those in healthy donors. The ASXL2 antibody levels were well associated with hypertension complication, but not with sex, body mass index, habitual smoking, or alcohol intake. These results suggest that the serum ASXL2 antibody marker can discriminate between hypertension-induced atherosclerotic AIS and AMI, as well as a number of digestive organ cancers.

Type 2 myocardial infarction: is it a geriatric syndrome?

Type 2 myocardial infarctions (T2-MI) is a type of necrosis that results from reduced oxygen supply and/or increased demand secondary to other causes unrelated to acute coronary atherothrombosis. The development and implementation of sensitive and high-sensitivity cardiac necrosis marker and the age-related increase of comorbidity lead to a boost of the frequency of T2-MI. T2-MI is often a complication of a high degree of clinical frailty in older adults, emerging as a "geriatric syndrome". Age-related non-cardiovascular causes may be the triggering factors and are strongly associated with the diagnosis, treatment, and prognosis of T2-MI. To date, there are no guidelines on management of this pathology in advancing age. Patient-centered approach and comprehensive geriatric assessment play a key role in the diagnosis, therapy and prognosis of geriatric patients with T2-MI.

Rapid RP-HPLC method for simultaneous estimation of metformin, pioglitazone, and glimepiride in human plasma

An isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed for rapid and simultaneous separation and estimation of 3 antidiabetic drugs, namely, metformin, pioglitazone, and glimepiride, in human plasma within 3 min. Separation was carried out on a MAGELLEN 5U C18 (5 μm, 150 mm × 4.60 mm) using a mobile phase of MeOH–0.025 M KH2PO4 adjusted to pH 3.20 using ortho-phosphoric acid (85:15, v/v) at ambient temperature. The flow rate was 1 mL/min, and the maximum absorption was measured at 235 nm. The retention time of metformin, pioglitazone, and glimepiride was noted to be 1.24, 2.32, and 2.77 min, respectively, indicating a very short analysis time compared to that of other reported methods. Also, limits of detection were reported to be 0.05, 0.26, and 0.10 μg/mL for metformin, pioglitazone, and glimepiride, respectively, showing a high degree of method sensitivity. The method was then validated according to the FDA guidelines for the determination of the three drugs clinically in human plasma, in particular, regarding pharmacokinetic and bioequivalence simulation studies.

Association of Pioglitazone with Increased Risk of Prostate Cancer and Pancreatic Cancer: A Functional Network Study

INTRODUCTION

The question of whether pioglitazone, an antidiabetic drug, increases the risk of cancer has been debated for some time. Recent studies have shown that pioglitazone use can increase the risk of prostate cancer as well as pancreatic cancer. However, it is unclear whether pioglitazone is a causal risk factor for these cancers.

METHODS

In this study, we aimed to explore the direct targets of pioglitazone and genes associated with this drug by querying open platforms in order to construct a biological function network, and then to further evaluate the relationships of pioglitazone with prostate cancer and pancreatic cancer.

RESULTS

We first tested our hypothesis using DrugBank and STRING. We identified four direct targets of pioglitazone and 50 pioglitazone-associated genes, which were then selected for KEGG pathway analysis using STRING and WebGestalt. This analysis generated the top 25 KEGG pathways, among which four pathways were related to site-specific cancers, including prostate cancer and pancreatic cancer. Finally, a genomic study using cBioPortal indicated that genomic alterations of two gene sets related to the prostate cancer and pancreatic cancer pathways, respectively, are associated with the acceleration of carcinogenesis.

CONCLUSIONS

Pioglitazone is likely to be a causal risk factor for prostate cancer and pancreatic cancer, so this drug should be used with caution. The present research also demonstrates the use of biological function network analysis to effectively explore drug interactions and drug safety profiles.

Chronic Niche Inflammation in Endometriosis-Associated Infertility: Current Understanding and Future Therapeutic Strategies

Endometriosis is an estrogen-dependent inflammatory disease that affects up to 10% of women of reproductive age and accounts for up to 50% of female infertility cases. It has been highly associated with poorer outcomes of assisted reproductive technology (ART), including decreased oocyte retrieval, lower implantation, and pregnancy rates. A better understanding of the pathogenesis of endometriosis-associated infertility is crucial for improving infertility treatment outcomes. Current theories regarding how endometriosis reduces fertility include anatomical distortion, ovulatory dysfunction, and niche inflammation-associated peritoneal or implantation defects. This review will survey the latest evidence on the role of inflammatory niche in the peritoneal cavity, ovaries, and uterus of endometriosis patients. Nonhormone treatment strategies that target these inflammation processes are also included. Furthermore, mesenchymal stem cell-based therapies are highlighted for potential endometriosis treatment because of their immunomodulatory effects and tropism toward inflamed lesion foci. Potential applications of stem cell therapy in treatment of endometriosis-associated infertility in particular for safety and efficacy are discussed.

Unique pharmacology of a novel allosteric agonist/sensitizer insulin receptor monoclonal antibody

Objective

Insulin resistance is a key feature of Type 2 Diabetes (T2D), and improving insulin sensitivity is important for disease management. Allosteric modulation of the insulin receptor (IR) with monoclonal antibodies (mAbs) can enhance insulin sensitivity and restore glycemic control in animal models of T2D.

Methods

A novel human mAb, IRAB-A, was identified by phage screening using competition binding and surface plasmon resonance assays with the IR extracellular domain. Cell based assays demonstrated agonist and sensitizer effects of IRAB-A on IR and Akt phosphorylation, as well as glucose uptake. Lean and diet-induced obese mice were used to characterize single-dose in vivo pharmacological effects of IRAB-A; multiple-dose IRAB-A effects were tested in obese mice.

Results

In vitro studies indicate that IRAB-A exhibits sensitizer and agonist properties distinct from insulin on the IR and is translated to downstream signaling and function; IRAB-A bound specifically and allosterically to the IR and stabilized insulin binding. A single dose of IRAB-A given to lean mice rapidly reduced fed blood glucose for approximately 2 weeks, with concomitant reduced insulin levels suggesting improved insulin sensitivity. Phosphorylated IR (pIR) from skeletal muscle and liver were increased by IRAB-A; however, phosphorylated Akt (pAkt) levels were only elevated in skeletal muscle and not liver vs. control; immunochemistry analysis (IHC) confirmed the long-lived persistence of IRAB-A in skeletal muscle and liver. Studies in diet-induced obese (DIO) mice with IRAB-A reduced fed blood glucose and insulinemia yet impaired glucose tolerance and led to protracted insulinemia during a meal challenge.

Conclusion

Collectively, the data suggest IRAB-A acts allosterically on the insulin receptor acting non-competitively with insulin to both activate the receptor and enhance insulin signaling. While IRAB-A produced a decrease in blood glucose in lean mice, the data in DIO mice indicated an exacerbation of insulin resistance; these data were unexpected and suggested the interplay of complex unknown pharmacology. Taken together, this work suggests that IRAB-A may be an important tool to explore insulin receptor signaling and pharmacology.

•

A novel anti-insulin receptor monoclonal antibody (IRAB-A) was identified that has both agonist and sensitizing activities.

•

IRAB-A increases the receptor's affinity for insulin by binding to an allosteric site and does not compete with insulin.

•

Mice injected once with IRAB-A show improved glycemia and reduced insulinemia, indicative of enhanced insulin sensitivity.

•

In diet induced obese mice, the insulin sensitizing effect of IRAB-A appears to depend on the degree of insulin resistance.

•

Chronic treatment of obese mice showed mixed effects on glucose homeostasis under normal fed or meal challenged conditions.

Therapeutic Strategies for Treatment of Inflammation-related Depression

BACKGROUND

Mounting evidence demonstrates enhanced systemic levels of inflammatory mediators in depression, indicating that inflammation may play a role in the etiology and course of mood disorders. Indeed, proinflammatory cytokines induce a behavioral state of conservation- withdrawal resembling human depression, characterized by negative mood, fatigue, anhedonia, psychomotor retardation, loss of appetite, and cognitive deficits. Neuroinflammation also contributes to non-responsiveness to current antidepressant (AD) therapies. Namely, response to conventional AD medications is associated with a decrease in inflammatory biomarkers, whereas resistance to treatment is accompanied by increased inflammation.

METHODS

In this review, we will discuss the utility and shortcomings of pharmacologic AD treatment strategies focused on inflammatory pathways, applied alone or as an adjuvant component to current AD therapies.

RESULTS

Mechanisms of cytokine actions on behavior involve activation of inflammatory pathways in the brain, resulting in changes of neurotransmitter metabolism, neuroendocrine function, and neuronal plasticity. Selective serotonin reuptake inhibitors exhibit the most beneficial effects in restraining the inflammation markers in depression. Different anti-inflammatory agents exhibit AD effects via modulating neurotransmitter systems, neuroplasticity markers and glucocorticoid receptor signaling. Anti-inflammatory add-on therapy in depression highlights such treatment as a candidate for enhancement strategy in patients with moderate-to-severe depression.

CONCLUSION

The interactions between the immune system and CNS are not only involved in shaping behavior, but also in responding to therapeutics. Even though, substantial evidence from animal and human research support a beneficial effect of anti-inflammatory add-on therapy in depression, further research with special attention on safety, particularly during prolonged periods of antiinflammatory co-treatments, is required.

Controversy of oral hypoglycemic agents in type 2 diabetes mellitus: Novel move towards combination therapies

AIM

As diabetes mellitus is multi-factorial disease, use of several oral hypoglycemic agents (OHAs) is the main stay of pharmacological treatment. The treatment has become more challenging and controversial as OHAs are heterogeneous in their mode of action that causes unwanted side effects. Complementary approaches such as use of medicinal plants and dietary polyunsaturated fatty acids (PUFA) with hypoglycemic and hypolipidemic activities are therefore imperative. A vast literature has independently documented the effects of OHAs, medicinal plants and PUFA for management of diabetes. In the present article, we have reviewed the current literature to describe the effects of commonly used OHAs, their mechanisms of action and reported controversies. The antidiabetic potential of herbs and/or formulations and omega-3 PUFA with its potential benefits and mode of action is also discussed.

METHODS

PUBMED, MEDLINE, Cochrane Library etc., were searched for relevant articles using appropriate terms (until February 2015). Human and animal studies were selected for the review. Data extraction was carried out by one author and checked by second author.

RESULTS

There is still controversy over the safety profile of OHAs. Medicinal herbs with hypoglycemic activities are increasingly sought because of its natural origin, active constituents and minimal side effects. The current literature suggests that supplementation with PUFA improves macro- and microvascular complications.

CONCLUSION

There is a need for best possible individualized treatment based on variations in biochemical parameters with combinational therapy of nutritional/herbal supplementations. Such a combination may be helpful for better management of diabetes and its complications.

Using Personalized Medicine in the Management of Diabetes Mellitus

Diabetes mellitus is a worldwide problem with an immense pharmacoeconomic burden. The multifactorial and complex nature of the disease lends itself to personalized pharmacotherapeutic approaches to treatment. Variability in individual risk and subsequent development of diabetes has been reported in addition to differences in response to the many oral glucose lowering therapies currently available for diabetes pharmacotherapy. Pharmacogenomic studies have attempted to uncover the heritable components of individual variability in risk susceptibility and response to pharmacotherapy. We review the current pharmacogenomics evidence as it relates to common oral glucose lowering therapies and how they can be utilized in the management of polygenic and monogenic forms of diabetes. Evidence supports the use of genetic testing and personalized approaches to the treatment of monogenic diabetes of the young. The data are not as robust for the current application of pharmacogenetic approaches to the treatment of polygenic type 2 diabetes mellitus, but there are suggestions as to future applications in this regard. We reviewed pertinent primary literature sources as well as current evidence-based guidelines on diabetes management.

The contribution of bone marrow-derived cells to the human adipocyte pool

White adipose tissue is a remarkably expandable organ with results in the last decade showing that human white adipocytes are continuously turned over during the entire life-span. Data primarily in murine models have demonstrated that adipocytes are derived from precursors present mainly in the perivascular areas of adipose tissue but their precise origin remains unclear. Subsets of cells present in bone marrow display a multipotent differentiation capacity which has prompted the hypothesis that bone marrow-derived cells (BMDCs) may also contribute to the adipocyte pool present in peripheral fat depots. This notion was initially demonstrated in a murine transplantation model, however, subsequent animal studies have been conflicting resulting in a debate of whether BMDCs actually differentiate into adipocytes or just fuse with resident fat cells. This controversy was recently resolved in 2 studies of human subjects undergoing bone marrow transplantation. Using a combination of different assays these data suggest that bone marrow contributes to at least 10% of the adipocyte pool. This proportion is doubled in obesity, suggesting that BMDCs may constitute a reserve pool for adipogenesis, particularly upon weight gain. This review discusses the possible mechanisms and relevance of these findings for human pathophysiology.

Anti-neuroinflammatory Activity of Elephantopus scaber L. via Activation of Nrf2/HO-1 Signaling and Inhibition of p38 MAPK Pathway in LPS-Induced Microglia BV-2 Cells

Elephantopus scaber L. (family: Asteraceae) has been traditionally utilized as a folkloric medicine and scientifically shown to exhibit anti-inflammatory activities in various in vivo inflammatory models. Given the lack of study on the effect of E. scaber in neuroinflammation, this study aimed to investigate the anti-neuroinflammatory effect and the underlying mechanisms of ethyl acetate fraction from the leaves of E. scaber (ESEAF) on the release of pro-inflammatory mediators in lipopolysaccharide (LPS)-induced microglia cells (BV-2). Present findings showed that ESEAF markedly attenuated the translocation of NF-κB to nucleus concomitantly with the significant mitigation on the LPS-induced production of NO, iNOS, COX-2, PGE₂, IL-1β, and TNF-α. These inflammatory responses were reduced via the inhibition of p38. Besides, ESEAF was shown to possess antioxidant activities evident by the DPPH and SOD scavenging activities. The intracellular catalase enzyme activity was enhanced by ESEAF in the LPS-stimulated BV-2 cells. Furthermore, the formation of ROS induced by LPS in BV-2 cells was reduced upon the exposure to ESEAF. Intriguingly, the reduction of ROS was found in concerted with the activation of Nrf2 and HO-1. It is conceivable that the activation promotes the scavenging power of antioxidant enzymes as well as to ameliorate the inflammatory response in LPS-stimulated BV-2 cells. Finally, the safety profile analysis through oral administration of ESEAF at 2000 mg/kg did not result in any mortalities, adverse effects nor histopathologic abnormalities of organs in mice. Taken altogether, the cumulative findings suggested that ESEAF holds the potential to develop as nutraceutical for the intervention of neuroinflammatory disorders.

Troglitazone, a PPAR-γ agonist, decreases LTC4 concentration in mononuclear cells in patients with asthma

BACKGROUND

Asthma is an inflammatory disorder with multiple mediators involved in the inflammatory response. Despite several attempts, no new anti-inflammatory drugs have been registered for asthma treatment for several years. However, thiazolidinediones, peroxisome proliferator-activated receptor agonists, have demonstrated some anti-inflammatory properties in various experimental settings. The aim of this study was to assess the influence of troglitazone on LTC₄ and 15-HETE concentrations. It also evaluates TNF-induced eotaxin synthesis in peripheral blood mononuclear cells from 14 patients with mild asthma and 13 healthy controls.

METHODS

PBMCs were isolated from the whole blood of the asthmatics and healthy subjects and pretreated with 0.1, 1 or 10μM of Troglitazone. The cells were then exposed to 10^-6M calcium jonophore or 10ng/ml TNF. The production and release of LTC₄, 15-HETE and eotaxin were then assessed.

RESULTS

Troglitazone caused a dose-dependent inhibition in LTC₄ synthesis in both asthmatics and healthy subjects. Troglitazone did not influence 15-HETE or eotaxin production in either asthmatic patients or in healthy individuals.

CONCLUSION

Due to its inhibition of LTC₄ synthesis, troglitazone therapy is an interesting potential therapeutic approach in asthma and other LTC₄ related inflammatory disorders.

Inflammation in Depression and the Potential for Anti-Inflammatory Treatment

Accumulating evidence supports an association between depression and inflammatory processes, a connection that seems to be bidirectional. Clinical trials have indicated antidepressant treatment effects for anti-inflammatory agents, both as add-on treatment and as monotherapy. In particular, nonsteroidal anti-inflammatory drugs (NSAIDs) and cytokine-inhibitors have shown antidepressant treatment effects compared to placebo, but also statins, poly-unsaturated fatty acids, pioglitazone, minocycline, modafinil, and corticosteroids may yield antidepressant treatment effects. However, the complexity of the inflammatory cascade, limited clinical evidence, and the risk for side effects stress cautiousness before clinical application. Thus, despite proof-of-concept studies of anti-inflammatory treatment effects in depression, important challenges remain to be investigated. Within this paper, we review the association between inflammation and depression together with the current evidence on use of anti-inflammatory treatment in depression. Based on this, we address the questions and challenges that seem most important and relevant to future studies, such as timing, most effective treatment lengths and identification of subgroups of patients potentially responding better to different anti-inflammatory treatment regimens.

Toward Precision Medicine: TBC1D4 Disruption Is Common Among the Inuit and Leads to Underdiagnosis of Type 2 Diabetes

OBJECTIVE

A common nonsense mutation in TBC1D4 was recently found to substantially increase the odds of type 2 diabetes in Greenlandic Inuit, leading to exclusively increased postprandial glucose. We investigated the frequency and effect of the TBC1D4 mutation on glucose metabolism and type 2 diabetes diagnosis among Canadian and Alaskan Inuit.

RESEARCH DESIGN AND METHODS

Exome sequencing of the TBC1D4 variant was performed in 114 Inuit from Nunavik, Canada, and Sanger sequencing was undertaken in 1,027 Alaskan Inuit from the Genetics of Coronary Artery Disease in Alaskan Natives (GOCADAN) Study. Association testing evaluated the effect of the TBC1D4 variant on diabetes-related metabolic traits and diagnosis.

RESULTS

The TBC1D4 mutation was present in 27% of Canadian and Alaskan Inuit. It was strongly associated with higher glucose (effect size +3.3 mmol/L; P = 2.5 x 10^-6) and insulin (effect size +175 pmol/L; P = 0.04) 2 h after an oral glucose load in homozygote carriers. TBC1D4 carriers with prediabetes and type 2 diabetes had an increased risk of remaining undiagnosed unless postprandial glucose values were tested (odds ratio 5.4 [95% CI 2.5-12]) compared with noncarriers. Of carriers with prediabetes or type 2 diabetes, 32% would remain undiagnosed without an oral glucose tolerance test (OGTT).

CONCLUSIONS

Disruption of TBC1D4 is common among North American Inuit, resulting in exclusively elevated postprandial glucose. This leads to underdiagnosis of type 2 diabetes, unless an OGTT is performed. Accounting for genetic factors in the care of Inuit with diabetes provides an opportunity to implement precision medicine in this population.

The effect of abscisic acid chronic treatment on neuroinflammatory markers and memory in a rat model of high-fat diet induced neuroinflammation

Background

Western diet and lifestyle are associated with overweight, obesity, and type 2 diabetes, which, in turn, are correlated with neuroinflammation processes. Exercise and a healthy diet are important in the prevention of these disorders. However, molecules inhibiting neuroinflammation might also be efficacious in the prevention and/or treatment of neurological disorders of inflammatory etiology. The abscisic acid (ABA) is a phytohormone involved in hydric-stress responses. This compound is not only found in plants but also in other organisms, including mammals. In rodents, ABA can play a beneficial role in the regulation of peripheral immune response and insulin action. Thus, we hypothesized that chronic ABA administration might exert a protective effect in a model of neuroinflammation induced by high-fat diet (HFD).

Methods

Male Wistar rats were fed with standard diet or HFD with or without ABA in the drinking water for 12 weeks. Glucose tolerance test and behavioral paradigms were performed to evaluate the peripheral and central effects of treatments. One-Way ANOVA was performed analyzed statistical differences between groups.

Results

The HFD induced insulin resistance peripherally and increased the levels of proinflammatory markers in in the brain. We observed that ABA restored glucose tolerance in HFD-fed rats, as expected. In addition, chronic ABA treatment rescued cognitive performance in these animals, while not affecting control diet fed animals. Moreover, it counteracted the changes induced by HFD in the hypothalamus; microglia activations and TNFα mRNA levels.

Conclusion

These results suggest that ABA might become a new therapeutic molecule improving the neuroinflammatory status and insulin resistance.

Does Thiazolidinedione therapy exacerbate fluid retention in congestive heart failure?

The ever-growing global burden of congestive heart failure (CHF) and type 2 diabetes mellitus (T2DM) as well as their co-existence necessitate that anti-diabetic pharmacotherapy will modulate the cardiovascular risk inherent to T2DM while complying with the accompanying restrictions imposed by CHF. The thiazolidinedione (TZD) family of peroxisome proliferator-activated receptor γ (PPARγ) agonists initially provided a promising therapeutic option in T2DM owing to anti-diabetic efficacy combined with pleiotropic beneficial cardiovascular effects. However, the utility of TZDs in T2DM has declined in the past decade, largely due to concomitant adverse effects of fluid retention and edema formation attributed to salt-retaining effects of PPARγ activation on the nephron. Presumably, the latter effects are potentially deleterious in the context of pre-existing fluid retention in CHF. However, despite a considerable body of evidence on mechanisms responsible for TZD-induced fluid retention suggesting that this class of drugs is rightfully prohibited from use in CHF patients, there is a paucity of experimental and clinical studies that investigate the effects of TZDs on salt and water homeostasis in the CHF setting. In an attempt to elucidate whether TZDs actually exacerbate the pre-existing fluid retention in CHF, our review summarizes the pathophysiology of fluid retention in CHF. Moreover, we thoroughly review the available data on TZD-induced fluid retention and proposed mechanisms in animals and patients. Finally, we will present recent studies challenging the common notion that TZDs worsen renal salt and water retention in CHF.

Rethinking Nuclear Receptors as Potential Therapeutic Targets for Retinal Diseases

Collectively, retinal diseases, including age-related macular degeneration, retinitis pigmentosa, and diabetic retinopathy, result in severe vision impairment worldwide. The absence and/or limited availability of successful drug therapies for these blinding disorders necessitates further understanding their pathobiology and identifying new targetable signaling pathways. Nuclear receptors are transcription regulators of many key aspects of human physiology, as well as pathophysiology, with reported roles in development, aging, and disease. Some of the pathways regulated by nuclear receptors include, but are not limited to, angiogenesis, inflammation, and lipid metabolic dysregulation, mechanisms also important in the initiation and development of several retinal diseases. Herein, we present an overview of the biology of three diseases affecting the posterior eye, summarize a growing body of evidence that suggests direct or indirect involvement of nuclear receptors in disease progression, and discuss the therapeutic potential of targeting nuclear receptors for treatment.

On the origin of human adipocytes and the contribution of bone marrow-derived cells

In the last decade, results in both animal models and humans have demonstrated that white adipocytes are generated over the entire life-span. This adds to the plasticity of adipose tissue and alterations in adipocyte turnover are linked to metabolic dysfunction. Adipocytes are derived from precursors present primarily in the perivascular areas of adipose tissue but their precise origin remains unclear. The multipotent differentiation capacity of bone marrow-derived cells (BMDC) has prompted the suggestion that BMDC may contribute to different cell tissue pools, including adipocytes. However, data in murine transplantation models have been conflicting and it has been a matter of debate whether BMDC actually differentiate into adipocytes or just fuse with resident fat cells. To resolve this controversy in humans, we recently performed a study in 65 subjects that had undergone bone marrow transplantation. Using a set of newly developed assays including single cell genome-wide analyses of mature adipocytes, we demonstrated that bone marrow contributes with approximately 10 % to the adipocyte pool. This proportion was more than doubled in obesity, suggesting that BMDC may constitute a reserve pool for adipogenesis, particularly upon weight gain. This commentary discusses the possible relevance of these and other recent findings for human pathophysiology.

Precision medicine: The future in diabetes care?

Personalized medicine aims at better targeting therapeutic intervention to the individual to maximize benefit and minimize harm. Type 2 diabetes (T2D) is a heterogeneous disease from a genetic, pathophysiological and clinical point of view. Thus, the response to any antidiabetic medication may considerably vary between individuals. Numerous glucose-lowering agents, with different mechanisms of action, have been developed, a diversified armamentarium that offers the possibility of a patient-centred therapeutic approach. In the current clinical practice, a personalized approach is only based upon phenotype, taking into account patient and disease individual characteristics. If this approach may help increase both efficacy and safety outcomes, there remains considerable room for improvement. In recent years, many efforts were taken to identify genetic and genotype SNP's (Single Nucleotide Polymorphism's) variants that influence the pharmacokinetics, pharmacodynamics, and ultimately the therapeutic response of oral glucose-lowering drugs. This approach mainly concerns metformin, sulphonylureas, meglitinides and thiazolidinediones, with only scarce data concerning gliptins and gliflozins yet. However, the contribution of pharmacogenetics and pharmacogenomics to personalized therapy still needs to mature greatly before routine clinical implementation is possible. This review discusses both opportunities and challenges of precision medicine and how this new paradigm may lead to a better individualized treatment of T2D.

A novel small-molecule agonist of PPAR-γ potentiates an anti-inflammatory M2 glial phenotype

Neuroinflammation is a key process for many neurodegenerative diseases. Activated microglia and astrocytes play an essential role in neuroinflammation by producing nitric oxide (NO), inflammatory cytokines, chemokines, and neurotoxins. Therefore, targeting glia-mediated neuroinflammation using small-molecules is a potential therapeutic strategy. In this study, we performed a phenotypic screen using microglia cell-based assay to identify a hit compound containing N-carbamoylated urethane moiety (SNU-BP), which inhibits lipopolysaccharide (LPS)-induced NO production in microglia. SNU-BP inhibited pro-inflammatory cytokines and inducible nitric oxide synthase in LPS-stimulated microglia, and potentiated interleukin-4-induced arginase-1 expression. PPAR-γ was identified as a molecular target of SNU-BP. The PPAR response element reporter assay revealed that SNU-BP specifically activated PPAR-γ, but not PPAR-δ or -α, confirming that PPAR-γ is the target protein of SNU-BP. The anti-inflammatory effect of SNU-BP was attenuated by genetic and pharmacological inhibition of PPAR-γ. In addition, SNU-BP induced an anti-inflammatory phenotype in astrocytes as well, by inhibiting pro-inflammatory NO and TNF-α, while increasing anti-inflammatory genes, such as arginase-1 and Ym-1. Finally, SNU-BP exhibited an anti-inflammatory effect in the LPS-injected mouse brain, demonstrating a protective potential for neuroinflammatory diseases.

Joint effects of diabetic-related genomic loci on the therapeutic efficacy of oral anti-diabetic drugs in Chinese type 2 diabetes patients

Previous pharmacogenomic studies of oral anti-diabetic drugs have primarily focused on the effect of a single site. This study aimed to examine the joint effects of multiple loci on repaglinide or rosiglitazone efficacy in newly diagnosed type 2 diabetes mellitus (T2DM) patients. A total of 209 newly diagnosed T2DM patients were randomly assigned to treatment with repaglinide or rosiglitazone for 48 weeks. The reductions in fasting glucose (ΔFPG), 2h glucose (Δ2hPG) and glycated hemoglobin (ΔHbA1c) levels were significantly associated with genetic score that was constructed using the sum of the effect alleles both in the repaglinide (P = 0.0011, 0.0002 and 0.0067, respectively) and rosiglitazone cohorts (P = 0.0002, 0.0014 and 0.0164, respectively) after adjusting for age, gender, body mass index and dosage. Survival analyses showed a trend towards a greater attainment rate of target HbA1c level in individuals with a high genetic score in the repaglinide cohort and rosiglitazone cohort (P_log-rank = 0.0815 and 0.0867, respectively) when the attainment of treatment targets were defined as more than 20% decrease of FPG, 2hPG, and HbA1c levels after treatment. In conclusion, we identified the joint effects of several T2DM-related loci on the efficacy of oral anti-diabetic drugs; moreover, we built a model to predict the drug efficacy.

Mouse Models as Predictors of Human Responses: Evolutionary Medicine

Mice offer a number of advantages and are extensively used to model human diseases and drug responses. Selective breeding and genetic manipulation of mice have made many different genotypes and phenotypes available for research. However, in many cases, mouse models have failed to be predictive. Important sources of the prediction problem have been the failure to consider the evolutionary basis for species differences, especially in drug metabolism, and disease definitions that do not reflect the complexity of gene expression underlying disease phenotypes. Incorporating evolutionary insights into mouse models allow for unique opportunities to characterize the effects of diet, different gene expression profiles, and microbiomics underlying human drug responses and disease phenotypes.