Muscle damage induced by experimental hypoglycemia

Characterization of metabolic alterations in the lean metabolically unhealthy alpha defensin transgenic mice

Inflammation is consistently linked to dysmetabolism. In transgenic mice (Def+/+) model the neutrophilic peptide, alpha defensin, proved atherogenic. This phenotype occurred despite favorable cholesterol and glucose levels, and lower body weight and blood pressure. In this study, integration of metabolic&behavioral phenotyping system, endocrine, biochemical and mitochondrial assessment, pathological and immunohistochemical tests, and multiple challenge tests was established to explore the metabolic impact of alpha defensin. Compared to the control group, Def+/+ mice exhibited lower total energy expenditure and carbohydrate utilization, and higher fat oxidation. Their ACTH-cortisol and thyroid profiles were intact. Intriguingly, they had low levels of glucagon, with high ammonia, uric acid, triglyceride, and lactate. Mitochondrial evaluations were normal. Overall, defensin-induced hypoglucagonemia is associated with lipolysis, restricted glucose oxidation, and enhanced wasting. Def+/+ mice may be a useful model for studying the category of lean, apparently metabolically healthy, and atherosclerotic phenotype, with insight into a potential inflammatory-metabolic link.

Surveilling brain damage using brain biomarkers in hypoglycemic neonatal calves with diarrhea

Hypoglycemia is a condition associated with neonatal diarrhea in calves, leading to increased mortality and neurological clinical signs. The aim of the present study was to determine the development of brain damage in hypoglycemic calves with neonatal diarrhea and the diagnostic and prognostic significance of these biomarkers. Ten healthy and 50 hypoglycemic calves with diarrhea were included in the study. Clinical examination, blood gases and complete blood count were performed at admission. Blood serum calcium-binding protein B (S100B), neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), ubiquitin carboxyl-terminal hydrolysis isoenzyme-1 (UCHL-1), activitin A (ACT), adrenomodullin (AM) concentrations, and creatine kinase-BB (CK-BB) enzyme activity were measured using commercial bovine-specific ELISA kits to assess brain damage. Of the hypoglycemic calves enrolled in the study, 13 (26%) survived and 37 (74%) died. In addition, 32 (64%) of the calves had severe acidosis and 24 (48%) had sepsis. S100B, GFAP, UCHL-1, CK-BB (p < 0.001) and NSE (p < 0.05) concentrations were significantly higher in hypoglycemic calves compared to healthy calves, while ACT concentrations were lower. Blood glucose concentration was negatively correlated with serum S100B, GFAP, UCHL-1, and CK-BB enzyme activity and positively correlated with ACT in hypoglycemic calves (p < 0.01). Brain injury biomarkers were not predictive of mortality (p > 0.05). Morever, severe hypoglycemia, severe acidosis and sepsis variables were not found to have sufficient capacity to predict mortality when considered alone or together (p > 0.05). In conclusion, brain damage may develop as a consequence of hypoglycemia in calves. S100B, NSE, GFAP, UCHL-1, ACT, and CK-BB concentrations can be used to diagnose brain damage in hypoglycemic calves. However, the variables of severe hypoglycemia, severe acidosis, and sepsis together with the biomarkers of brain injury have a limited value in predicting the prognosis of neonatal calves with diarrhea.

Clinical analysis of the serum muscle enzyme spectrum of patients with newly diagnosed Sheehan's syndrome

We investigated the factors associated with serum muscle enzyme elevation in patients with Sheehan's syndrome. A total of 48 patients who were newly diagnosed with Sheehan's syndrome were included and divided into 3 groups: Group 1, creatine kinase (CK) ≥ 1000 U/L; Group 2, 140 < CK < 1000 U/L; and Group 3, CK ≤ 140 U/L. Differences in serum muscle enzymes, serum electrolytes, blood glucose and hormones were compared among the 3 groups. A Spearman correlation analysis and multiple linear regression analysis were performed on serum muscle enzymes and the other variables. Four patients in Group 1 underwent electromyography. Fourteen, 26 and 8 patients were divided into Group 1, Group 2, and Group 3, respectively. The levels of plasma osmolality, serum sodium, free triiodothyronine (FT3) and free thyroxine (FT4) in Group 1 were lower than those in Group 3 at admission (P < .05). There were significant differences in CK, CK-MB, aspartate aminotransferase, lactate dehydrogenase, and alpha-hydroxybutyrate dehydrogenase among the three groups (P < .05). CK was correlated with serum sodium (r = -0.642, P < .001), serum potassium (r = -0.29, P = .046), plasma osmolality (r = -0.65, P < .001), FT3 (r = -0.363, P = .012), and FT4 (r = -0.450, P = .002). Moreover, creatine kinase isoenzyme-MB (CK-MB) was correlated with serum sodium (r = -0.464, P = .001) and plasma osmolality (r = -0.483, P < .001). The multiple linear regression showed that serum sodium was independently and negatively correlated with CK (r = -0.352, P = .021). The electromyogram results supported the existence of myogenic injury. Sheehan's syndrome is prone to be complicated by nontraumatic rhabdomyolysis, with both a chronic course and acute exacerbation. Serum muscle enzymes should be routinely measured. For patients with CK levels > 1000 U/L, a CK-MB/CK ratio < 6% can be a simple indicator to differentiate rhabdomyolysis from acute myocardial infarction. Abnormal serum muscle enzymes observed in Sheehan's syndrome may be associated with hypothyroidism and with hyponatremia in particular.

Problematic drinking in the old and its association with muscle mass and muscle function in type II diabetes

Problematic drinking behavior is common in the old and negative consequences of hypoglycemic episodes in type 2 diabetes (T2D) as a result of alcohol consumption have been described previously. Although, associations between such hypoglycemic episodes with reduced muscle mass are discussed, it is uncertain if problematic drinking behavior drives decline of muscle mass and/or muscle function. In the current study, we analyzed data of the Berlin Aging Study II (BASE-II) to examine the association of problematic drinking behavior with muscle mass and grip strength in T2D. Cross-sectional data of 1451 old BASE-II participants (51.6% women; 60–84 years old) were analyzed. Problematic drinking behavior was assessed using the Alcohol Use Identification Test (AUDIT). Muscle mass was measured using dual energy X-ray absorptiometry (DXA), grip strength using a Smedley dynamometer. Adjusted regression models were calculated to assess the association of problematic drinking with muscle mass and grip strength. Problematic drinking was evident in 11.2% of BASE-II participants and in 12.5% of BASE-II participants diabetes was evident. In the fully adjusted model (adjusted for age, trunk fat mass, HbA1c, antidiabetic medication, TSH, CRP, testosterone, physical inactivity, depression (GDS-score), morbidities, smoking status and total energy intake/day, we found a statistically significant association between problematic drinking and muscle mass (β-3.7, SE: 1.3, R² 0.481, partial eta square 0.166, observed power 0.816, p-value 0.005) and grip strength (β-8.1, SE: 3.3, R² 0.222, partial eta square 0.134, observed power 0.670, p-value 0.018) in old diabetic men. These associations were not evident in women and subjects without T2D. Problematic drinking behavior was associated with lower muscle mass and grip strength in old men with diabetes. This topic should be addressed in these subjects as they could be at increased risk for early functional decline, sarcopenia or frailty.

Atrazine is primarily responsible for the toxicity of long-term exposure to a combination of atrazine and inorganic arsenic in the nigrostriatal system of the albino rat

Chronic and simultaneous exposure to a variety of chemicals present in the environment is an unavoidable fact. However, given the complexity of studying chemical mixtures, most toxicological studies have focused on the effects of short-term exposure to single substances. The aim of this study was to evaluate the effects on the nigrostriatal system of the chronic, simultaneous exposure to two widely distributed substances that have been identified as potential dopaminergic system toxicants, inorganic arsenic (iAs) and atrazine (ATR). Six groups of rats were treated daily for one year with atrazine (10mg ATR/kg), inorganic arsenic (0.5 or 50mgiAs/L of drinking water), or a combination of ATR+0.5mgiAs/L or ATR+50mgiAs/L. The 50mgiAs/L group showed locomotor hypoactivity, while all treatments decreased motor coordination in contrast no effects of treatment were found on the place and response learning tasks. Regarding markers for liver and muscle damage, there were no differences between groups in creatine kinase (CK) or aspartate transaminase (AST) activities, while decreases in lactate dehydrogenase (LDH) levels were found in some exposed groups. The striatal DA content was significantly reduced in ATR, 0.5mgiAs/L, ATR+0.5mgiAs/L, and ATR+50mgiAs/L groups, in comparison to the control group. The number of mesencephalic tyrosine hydroxylase positive cells decreased in the ATR and ATR+0.5mgiAs/L groups compared to the control. In contrast, immunoreactivity to cytochrome oxidase was reduced compared to the control in all treated groups, except for the group treated with 0.5iAsmg alone. Our results indicate that ATR has deleterious effects on dopaminergic neurons and that the combination of ATR and iAs does not exacerbate these effects.

Glutathione suppresses increase of serum creatine kinase in experimental hypoglycemia

Inhibitory effects of reduced glutathione (GSH) on serum enzymes including alanine aminotransferase (AST), lactate dehydrogenase (LDH) and creatine kinase (CK) were investigated in the hypoglycemic rabbits. Hypoglycemia lasting for 60 min was induced by intravenous injection of insulin (10U/kg) and then recovered by intravenous glucose injection. Serum levels of ALT, AST, LDH and CK increased significantly (p<0.05) at 6h after the induction of hypoglycemia. Plasma GSH, oxidized glutathione (GSSG) and total glutathione (TGSH) began to increase significantly (p<0.05) at 1h after the insulin injection, and GSSG/TGSH ratio rose significantly (p<0.05) at 6h after the induction of hypoglycemia. GSSG contents and GSSG/TGSH ratio in quadriceps significantly increased during hypoglycemia. Administration of GSH significantly decreased plasma GSSG levels, GSSG/TGSH ratio (p<0.05) and suppressed the rise of serum enzymes induced by hypoglycemia. These results suggest that GSH administration may play a preventive role for increases of serum enzymes by experimental hypoglycemia.

Rise in plasma oxidized glutathione by experimental hypoglycemia

Changes in plasma glutathione were investigated under hypoglycemic status. Twelve rabbits were randomly divided into hypoglycemic group (n=6) and saline-injected control group (n=6). Hypoglycemia was induced by intravenous injection of insulin as 10 U/kg and recovered by intravenous glucose injection after 60 minutes. In the control group, saline was intravenously injected in stead of insulin. Plasma levels of oxidized glutathione (GSSG) rose significantly (p<0.01) and remarkably decrease in plasma GSH/GSSG ratio (p<0.05) accompanying increase in serum enzymes in the hypoglycemic group. These results suggest that hypoglycemia might cause change in plasma GSSG which is related to increase of serum enzymes by hypoglycemia.