Obesity and to a greater extent type-2 diabetes are associatedwith impaired glucose utilization and peripheral neuropathy.Different studies demonstrated that diet-induced obese ratsdevelop whole-body insulin resistance and sensory neuropathyassociated with reduced sensory nerve conduction velocity, ther-mal hypoalgesia and decreased intraepidermal nerve fiber densi-ty in the skin. The prediabetic stage is a leading cause of periph-eral neuropathy, accounting for approximately 35.5% of undiag-nosed cases. Moreover, dyslipidemia may contribute to the devel-opment of peripheral neuropathy. The aim of this study was toevaluate the effects of a high-fat diet (HFD) on the sciatic nervein the rodent model of diet-induced obesity (DIO). DIO ratsexposed to high-fat diet ad libitum, provide a useful animal modelsharing several common features with human obesity. DIO ratswere studied after 5 weeks when the obese phenotype appearedand after 17 weeks of the HFD. They were compared to the con-trol rats with no fat diet (CHOW). Histochemical, immunohisto-chemical and immunochemical analysis were performed to eval-uate nerve fiber changes of the sciatic nerve. Systolic blood pres-sure, glycaemia and insulin levels were higher in DIO rats onlyafter 17 weeks of the HFD. No changes in total cholesterol andtriglycerides were found. An increase of thiobarbituric reactivesubstances and oxidated proteins was observed in the serum ofDIO rats compared to CHOW. Axon area and myelin thicknessdid not change in large and small nerve fibers in DIO rats. Adecrease of 200-kDa neurofilament immunoreactivity and areduced expression of myelin basic like-protein were observed inobese rats compared to the control. An inflammatory condition,with an increase of interleukin-band oxidative stress weredetected in the sciatic nerve of the obese rat. Our findings sup-port the hypothesis that obesity, characterized by hyperglycaemiaand adipose tissue accumulation, may represent a risk factor forneuropathy.
Peripheral neuropathy related to obesity: a microanatomical study of sciatic nerve in obese rats.
Tomassoni D;Martinelli I;Moruzzi M;Traini E;Micioni Di Bonaventura MV;Cifani C;Amenta F;
2019-01-01
Abstract
Obesity and to a greater extent type-2 diabetes are associatedwith impaired glucose utilization and peripheral neuropathy.Different studies demonstrated that diet-induced obese ratsdevelop whole-body insulin resistance and sensory neuropathyassociated with reduced sensory nerve conduction velocity, ther-mal hypoalgesia and decreased intraepidermal nerve fiber densi-ty in the skin. The prediabetic stage is a leading cause of periph-eral neuropathy, accounting for approximately 35.5% of undiag-nosed cases. Moreover, dyslipidemia may contribute to the devel-opment of peripheral neuropathy. The aim of this study was toevaluate the effects of a high-fat diet (HFD) on the sciatic nervein the rodent model of diet-induced obesity (DIO). DIO ratsexposed to high-fat diet ad libitum, provide a useful animal modelsharing several common features with human obesity. DIO ratswere studied after 5 weeks when the obese phenotype appearedand after 17 weeks of the HFD. They were compared to the con-trol rats with no fat diet (CHOW). Histochemical, immunohisto-chemical and immunochemical analysis were performed to eval-uate nerve fiber changes of the sciatic nerve. Systolic blood pres-sure, glycaemia and insulin levels were higher in DIO rats onlyafter 17 weeks of the HFD. No changes in total cholesterol andtriglycerides were found. An increase of thiobarbituric reactivesubstances and oxidated proteins was observed in the serum ofDIO rats compared to CHOW. Axon area and myelin thicknessdid not change in large and small nerve fibers in DIO rats. Adecrease of 200-kDa neurofilament immunoreactivity and areduced expression of myelin basic like-protein were observed inobese rats compared to the control. An inflammatory condition,with an increase of interleukin-band oxidative stress weredetected in the sciatic nerve of the obese rat. Our findings sup-port the hypothesis that obesity, characterized by hyperglycaemiaand adipose tissue accumulation, may represent a risk factor forneuropathy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
