The prevalence of cardio-metabolic risk factors is differentially elevated in obesity-prone Osborne-Mendel and obesity-resistant S5B/Pl rats

AIMS

Individual susceptibility to develop obesity may impact the development of cardio-metabolic risk factors that lead to obesity-related comorbid conditions. Obesity-prone Osborne-Mendel (OM) rats expressed higher levels of visceral adipose inflammation than obesity-resistant, S5B/Pl (S5B) rats. However, the consumption of a high fat diet (HFD) differentially affected OM and S5B rats and induced an increase in visceral adipose inflammation in S5B rats. The current study examined the effects of HFD consumption on cardio-metabolic risk factors in OM and S5B rats.

MATERIALS & METHODS

Glucose regulation and circulating levels of lipids, adiponectin and C-reactive protein were assessed following 8 weeks of HFD or low fat diet (LFD) consumption. Left ventricle hypertrophy and mRNA expression of cardiovascular disease biomarkers were also quantified in OM and S5B rats.

KEY FINDINGS

Circulating levels of triglycerides were higher, while HDL cholesterol, adiponectin and glycemic control were lower in OM rats, compared to S5B rats. In the left ventricle, BNP and CTGF mRNA expression were higher in OM rats and IL-6, IL-1β, VEGF, and iNOS mRNA expression were higher in S5B rats.

SIGNIFICANCE

These findings support the hypothesis that cardio-metabolic risk factors are increased in obesity-prone individuals, which may increase the risk for the development of obesity-related comorbidities. In the current models, obesity-resistant S5B rats also exhibited cardiovascular risk factors supporting the importance of monitoring cardiovascular health in individuals characterized as obesity-resistant.

Alcohol Vapor Inhalation as a Model of Alcohol-Induced Organ Disease

BACKGROUND

Chronic intermittent ethanol vapor (CIEV) exposure has been used extensively to produce rodent models of alcohol dependence, but unlike other models of alcohol abuse, CIEV has not been assessed as a model of end-organ damage. The purpose of this study was to characterize the effects of CIEV on peripheral organ systems affected by alcohol abuse, including the liver, lungs, and cardiovascular system.

METHODS

Adult male Sprague-Dawley rats were exposed to daily CIEV for a period of 8 weeks (14HR ON/10HR OFF), producing blood alcohol levels of ~200 mg/dl. Controls were exposed to room air. After 8 weeks, echocardiography was performed to assess cardiac function. Indices of liver injury (alanine and aspartate aminotransferases [ALT and AST]; cytochrome p450 2E1 [CYP2E1]; alcohol dehydrogenase [ADH]; Oil Red O and triglyceride content; lipid peroxidation; inflammatory cytokine expression; and macrophage infiltration), and lung inflammatory cell count, proinflammatory cytokine expression, and lipid peroxidation were measured.

RESULTS

Left ventricular posterior wall thickness was significantly decreased, and systolic blood pressure was significantly elevated by CIEV compared with air controls. CIEV led to a significant increase in plasma ALT and triglycerides compared with room air controls. CIEV did not affect liver triglyceride content, lipid staining or peroxidation, but increased CYP2E1 and chemokine (C-C motif) ligand 2 (CCL2) protein expression, while decreasing ADH expression. CIEV significantly increased numbers of both polymorphonuclear neutrophils and lymphocytes in the bronchoalveolar lavage fluid, indicative of pulmonary inflammation. However, CIEV did not produce significant changes in lung mass, pulmonary lipid peroxidation, inflammatory cytokine expression, or edema.

CONCLUSIONS

These results show that CIEV produces hepatic, pulmonary, and cardiovascular effects in rats similar to those found in other models of chronic alcohol administration. Alcohol vapor administration is a novel method of alcohol-induced tissue injury with high potential for widespread use in alcohol toxicology research.

Alcohol's Burden on Immunity Following Burn, Hemorrhagic Shock, or Traumatic Brain Injury

Alcohol consumption contributes to increased incidence and severity of traumatic injury. Compared with patients who do not consume alcohol, alcohol-consuming patients have higher rates of long-term morbidity and mortality during recovery from injury. This can be attributed in part to an impaired immune response in individuals who consume alcohol. Acute and chronic alcohol use can affect both the innate and adaptive immune defense responses within multiple organ systems; the combination of alcohol use and injury results in increased susceptibility to bacterial and viral pathogens. This review examines the major deleterious effects of alcohol on immunity following tissue damage or traumatic injury, with a focus on alcohol's influence on the ability of the immune and major organ systems to fight disease and to repair damaged tissues following injury.