Acetaminophen normalizes glucose homeostasis in mouse models for diabetes
ABSTRACT Loss of pancreatic beta cell insulin secretion is the most important element in the progression of type 1 and type 2 diabetes. Since oxidative stress is involved in the progressive loss of beta cell function, we evaluated the potential for the over-the-counter analgesic drug and antioxidant, acetaminophen (APAP), to intervene in the diabetogenic process. We used mouse models for type 1 diabetes (streptozotocin) and type 2 diabetes (high-fat diet) to examine the ability of APAP to intervene in the progression of diabetes. In C57BL/6J mice, streptozotocin caused a dosage dependent increase in fasting blood glucose (FBG), from 100 to >600mg/dl. Daily APAP (20mg/kg BW, gastric gavage), significantly prevented and partially reversed the increase in FBG levels produced by streptozotocin. After 10 weeks on a high-fat diet, mice developed fasting hyperinsulemia and impaired glucose tolerance compared to animals fed a control diet. APAP largely prevented these changes in insulin and glucose tolerance. Furthermore, APAP prevented most of the increase in body fat in mice fed the high-fat diet. One protective mechanism for APAP is suggested by studies using isolated liver mitochondria, where low micromolar concentrations abolished the production of reactive oxygen that might otherwise contribute to the destruction of pancreatic beta-cells. These findings suggest that administration of APAP to mice, in a dosage used safely by humans, reduces the production of mitochondrial reactive oxygen and concomitantly prevents the development of type 1 and type 2 diabetes in established animal models.
- SourceAvailable from: Sergey Lupachyk
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- "A beneficial effect of salubrinal on HFD-induced prediabetic neuropathy in the current study is likely mediated through both amelioration of the prediabetic condition per se, and the biochemical changes in the peripheral nervous system independent of the wholebody glucose homeostasis. Our findings are in line with several previous reports (Hoehn et al., 2009; Shertzer et al., 2008; Weisberg et al., 2008) indicating that a HFD-fed mouse is not an ideal model for dissection of pathogenetic mechanisms underlying prediabetes-associated end-organ damage, because pharmacological and genetic manipulations abrogating oxidative and now ER stress in this model interfere with the HFD-induced prediabetic phenotype per se. Evaluation of salubrinal on neuropathy in other models of prediabetes and in overt diabetes has never been performed. "
ABSTRACT: Growing evidence suggests that prediabetes and metabolic syndrome are associated with increased risk for the development of microvascular complications including retinopathy, nephropathy, and, most commonly, peripheral painful neuropathy and/or autonomic neuropathy. The etiology of these disabling neuropathies is unclear, and several clinical and experimental studies implicated obesity, impaired fasting glycemia/impaired glucose tolerance, elevated triglyceride and non-esterified fatty acids, as well as oxidative-nitrative stress. Endoplasmic reticulum stress resulting from abnormal folding of newly synthesized proteins and leading to the impairment of metabolism, transcriptional regulation, and gene expression, is emerging as a key mechanism of metabolic diseases including obesity and diabetes. We evaluated the role for this phenomenon in prediabetic neuropathy using two animal models i.e., Zucker (fa/fa) rats and high-fat diet fed mice which displayed obesity and impaired glucose tolerance in the absence of overt hyperglycemia. Endoplasmic reticulum stress manifest in upregulation of the glucose-regulated proteins BiP/GRP78 and GRP94 of unfolded protein response was identified in the sciatic nerve of Zucker rats. A chemical chaperone, trimethylamine oxide, blunted endoplasmic reticulum stress and alleviated sensory nerve conduction velocity deficit, thermal and mechanical hypoalgesia, and tactile allodynia. A selective inhibitor of eukaryotic initiation factor-2α dephosphorylation, salubrinal, improved glucose intolerance and alleviated peripheral nerve dysfunction in high-fat diet fed mice. Our findings suggest an important role of endoplasmic reticulum stress in the neurobiology of prediabetic peripheral neuropathy, and identify a new therapeutic target.Experimental Neurology 11/2012; 247. DOI:10.1016/j.expneurol.2012.11.001 · 4.62 Impact Factor
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- "Both models exhibit nerve conduction deficit, small sensory nerve fiber dysfunction, and clearly manifested oxidative-nitrosative stress in the peripheral nerve and vasa nervorum      and are, therefore, suitable for dissection of relative contribution of these phenomena to peripheral neuropathy in prediabetes. Zucker fa/fa rat with genetically predetermined obesity, hyperinsulinemia, and other afore-mentioned metabolic abnormalities is the preferential model for this kind of studies, as many pharmacological interventions, including those alleviating oxidative stress, have been reported to interfere with the prediabetic condition per se in high-fat diet fed rodents   . "
ABSTRACT: Peripheral neuropathy develops in human subjects with prediabetes and metabolic syndrome before overt hyperglycemia. The contributions of impaired glucose tolerance and insulin signaling, hypertriglyceridemia and/or increased nonesterified fatty acids (NEFA), and hypercholesterolemia to this condition remain unknown. Niacin and its derivatives alleviate dyslipidemia with a minor effect on glucose homeostasis. This study evaluated the roles of impaired glucose tolerance versus dyslipidemia in prediabetic neuropathy using Zucker fatty (fa/fa) rats and the niacin derivative acipimox, as well as the interplay of hypertriglyceridemia, increased NEFA, and oxidative-nitrosative stress. Sixteen-week-old Zucker fatty rats with impaired glucose tolerance, obesity, hyperinsulinemia, hypertriglyceridemia, hypercholesterolemia, and increased NEFA displayed sensory nerve conduction velocity deficit, thermal and mechanical hypoalgesia, and tactile allodynia. Acipimox (100 mg kg(-1) day(-1), 4 weeks) reduced serum insulin, NEFA, and triglyceride concentrations without affecting glucose tolerance and hypercholesterolemia. It alleviated sensory nerve conduction velocity deficit and changes in behavioral measures of sensory function and corrected oxidative-nitrosative stress, but not impaired insulin signaling, in peripheral nerve. Elevated NEFA increased total and mitochondrial superoxide production and NAD(P)H oxidase activity in cultured human Schwann cells. In conclusion, hypertriglyceridemia and/or increased NEFA concentrations cause prediabetic neuropathy through oxidative-nitrosative stress. Lipid-lowering agents and antioxidants may find a use in the management of this condition.Free Radical Biology and Medicine 02/2012; 52(8):1255-63. DOI:10.1016/j.freeradbiomed.2012.01.029 · 5.71 Impact Factor
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- "POPULATION-BASED DISCOVERY OF BIOMARKERS expression by glucose, was decreased as the degree of liver necrosis increased in animals treated with acetaminophen. Several recent studies demonstrated that acetaminophen can affect blood glucose levels (Kendig et al., 2008) and improve glucose tolerance in mice fed a high-fat diet (Shertzer et al., 2008). The former study showed that daily administration of acetaminophen prevented approximately 70% of weight gain compared to mice fed the highfat diet alone, even at a daily dose that was lower than half of the maximum recommended weight-adjusted human dose (Kendig et al., 2008). "
ABSTRACT: Toxicogenomic studies are increasingly used to uncover potential biomarkers of adverse health events, enrich chemical risk assessment, and to facilitate proper identification and treatment of persons susceptible to toxicity. Current approaches to biomarker discovery through gene expression profiling usually utilize a single or few strains of rodents, limiting the ability to detect biomarkers that may represent the wide range of toxicity responses typically observed in genetically heterogeneous human populations. To enhance the utility of animal models to detect response biomarkers for genetically diverse populations, we used a laboratory mouse strain diversity panel. Specifically, mice from 36 inbred strains derived from Mus mus musculus, Mus mus castaneous, and Mus mus domesticus origins were treated with a model hepatotoxic agent, acetaminophen (300 mg/kg, ig). Gene expression profiling was performed on liver tissue collected at 24 h after dosing. We identified 26 population-wide biomarkers of response to acetaminophen hepatotoxicity in which the changes in gene expression were significant across treatment and liver necrosis score but not significant for individual mouse strains. Importantly, most of these biomarker genes are part of the intracellular signaling involved in hepatocyte death and include genes previously associated with acetaminophen-induced hepatotoxicity, such as cyclin-dependent kinase inhibitor 1A (p21) and interleukin 6 signal transducer (Il6st), and genes not previously associated with acetaminophen, such as oncostatin M receptor (Osmr) and MLX interacting protein like (Mlxipl). Our data demonstrate that a multistrain approach may provide utility for understanding genotype-independent toxicity responses and facilitate identification of novel targets of therapeutic intervention.Toxicological Sciences 06/2009; 110(1):235-43. DOI:10.1093/toxsci/kfp096 · 4.48 Impact Factor