Association of cyclin D1 G870A polymorphism with susceptibility to gastric cancers in Korean male patients

Cyclin D1 is a key cell cycle regulator that is upregulated in gastric cancer. The common G870A polymorphism of cyclin D1 which can influence cancer susceptibility and disease outcome has been the most frequently investigated. The specific aim of this study is to investigate whether the G870A polymorphism of cyclin D1 was associated with individual susceptibility to gastric cancer in Korea. The frequency of the polymorphism was examined in 253 gastric cancer patients and 442 healthy controls. Polymorphism analysis was performed by amplifying exon 4 of cyclin D1 and sequencing the products. The frequencies of genotypes: G/G, G/A and A/A were 28.1% (71/253), 49.4% (125/253) and 22.5% (57/253), respectively, in gastric cancer cases, and 23.1%, 51.1% and 25.8%, respectively, in healthy controls. Statistically, the polymorphism was not associated with increased risk of gastric cancer. When stratified by histological subtype of gastric cancer, the risk was also not statistically significant. However, the male gastric cancer patients showed a significantly higher proportion of the homozygous G/G genotype and the G allele (Chi-Square test, P = 0.0242 & P = 0.0307) compared to males in the control group. Thus, our findings suggested that the G870A polymorphism of cyclin D1 was not associated with an increased risk for gastric cancer in this population, however, it may contribute to susceptibility to gastric cancer in men.

Effects of chronic angiotensin II receptor antagonist and angiotensin-converting enzyme inhibitor treatments on neurohormonal levels and haemodynamics during cardiopulmonary bypass

BACKGROUND

Chronic treatment with renin-angiotensin system (RAS) antagonists frequently causes deleterious hypotension during anaesthesia. We compared the effects of angiotensin II receptor antagonists (ARA) and angiotensin-converting enzyme inhibitors (ACEI) on neurohormonal levels and haemodynamics during cardiopulmonary bypass (CPB).

METHODS

Forty-four patients undergoing mitral valvular surgery who were treated with either ARA (ARA group, n=14) or ACEI (ACEI group, n=15) over 12 weeks or who were not treated with any RAS antagonist (control group, n=15) were enrolled. The plasma levels of epinephrine, norepinephrine, arginine vasopressin (AVP) and angiotensin II, and haemodynamic variables were measured before (T1) and 15 min after (T2) the start of CPB, before aortic unclamping (T3) and at skin closure (T4). Mean arterial pressure (MAP) was maintained above 60 mm Hg with phenylephrine administration during CPB.

RESULTS

The plasma epinephrine, norepinephrine, AVP and angiotensin II levels increased during CPB in all groups. Compared with the control group, the AVP level was lower at T1 in the ARA group and at T2 in the ARA and ACEI groups. The angiotensin II level was higher at T1, T2 and T3 in ARA group compared with ACEI and control groups. There were no significant differences in the epinephrine and norepinephrine levels among the three groups. The amount of administered phenylephrine during CPB was greater and MAP was lower in the ARA group compared with the ACEI and control groups.

CONCLUSIONS

Chronic ARA treatment resulted in more profound hypotension than ACEI treatment during CPB, and this may be associated with the blockade of angiotensin II receptors by ARA.

Mitochondrial dysfunction induces aberrant insulin signalling and glucose utilisation in murine C2C12 myotube cells

AIMS/HYPOTHESIS

Mitochondrial dysfunction is considered a critical component in the development of diabetes. The aim of this study was to elucidate the molecular mechanisms involved in the development of insulin resistance and diabetes through investigation of mitochondrial retrograde signalling.

MATERIALS AND METHODS

Mitochondrial function of C2C12 myotube cells was impaired by genetic (ethidium bromide) and metabolic (oligomycin) stress, and changes in target molecules related to insulin signalling were analysed.

RESULTS

Concomitant with reductions in mitochondrial membrane potential (DeltaPsim) and ATP synthesis, production of IRS1 and solute carrier family 2 (facilitated glucose transporter), member 4 (SLC2A4, formerly known as GLUT4) were reduced. Moreover, serine phosphorylation of IRS1 increased, resulting in decreased tyrosine phosphorylation. This indicates that mitochondrial dysfunction decreases insulin-stimulated SLC2A4 translocation and glucose uptake. Mitochondrial stress activated c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) signalling in a Ca(2+)-dependent manner, and removal of free Ca(2+) by BAPTA-AM, as well as inhibition of JNK and p38 MAPK, abrogated mitochondrial stress-induced reductions in IRS1 and SLC2A4 production. Mitochondrial dysfunction after oligomycin treatment significantly increased levels of activating transcription factor 3 (ATF3), which represses Irs1 promoter activity. Removal of the 5' flanking region of Irs1 demonstrated that the promoter region within 191 bases from the transcription site may be involved in the transcriptional repression of Irs1 by mitochondrial stress.

CONCLUSIONS/INTERPRETATION

We show distinct mitochondrial retrograde signalling, where Irs1 is downregulated through ATF3 in a Ca(2+)-, JNK- and p38 MAPK-dependent manner, and IRS1 is inactivated. Therefore, mitochondrial dysfunction causes aberrant insulin signalling and abnormal utilisation of glucose, as observed in many insulin resistance states.

Cholecysto-urachal fistula

The urachus is an embryonic remnant that connects the primitive bladder to the allantois. Multiple urachal anomalies have been described, including the urachal sinus, urachal cyst, patent urachus, and urachal diverticulum. We describe an unusual case in which a patient with urinary tract infection and dysuria was ultimately found to have urinary gallstones from a urachal connection with the gallbladder.

On the relationship between speech- and nonspeech-evoked auditory brainstem responses

Auditory brainstem response (ABR) reflects activation of the neural generators along the ascending auditory pathway when a sound is heard. In this study, we explored the relationship between brainstem encoding of click and speech signals in normal-learning children and in those with language-based learning problems. To that end, ABR was recorded from both types of stimuli. We found that the normal pattern of correlation between click- and speech-evoked ABRs was disrupted when speech-evoked ABRs were delayed. Thus, delayed responses to speech were not indicative of clinically abnormal responses to clicks. We conclude that these two responses reflect largely separate neural processes and that only processes involved in encoding complex signals such as speech are impaired in children with learning problems.

The inhibitory effects of roflumilast on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells are mediated by heme oxygenase-1 and its product carbon monoxide

OBJECTIVES

Heme oxygenase-1 (HO-1) is an enzyme that degrades heme into biliverdin, free iron, and carbon monoxide (CO). This enzyme is known to have cytoprotective and anti-inflammatory effects. In this study, we investigated whether roflumilast, a newly developed specific phosphodiesterase 4 (PDE4) inhibitor, mediates some of its anti-inflammatory effects by blocking nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha) via the induction of HO-1 expression in macrophages.

METHODS

The expression of iNOS and HO-1 was analyzed by western blot analysis. The production of NO and TNF-alpha was assayed by Greiss and ELISA, respectively.

RESULTS

Roflumilast markedly suppressed LPS-induced NO and TNF-alpha production and these phenomena were correlated with the induction of HO-1 protein levels. Moreover, the inhibitory effects of roflumilast on NO production were abrogated by a HO-1 inhibitor and a CO scavenger. Tricarbonyldichlrororuthenium(II) dimer, a CO releasing molecule significantly suppressed NO production.

CONCLUSIONS

These results suggested that roflumilast exerts its anti-inflammatory effects in macrophages through a novel mechanism that involves the action of HO-1 and its product, CO.

Cyclin-dependent kinase-5 prevents neuronal apoptosis through ERK-mediated upregulation of Bcl-2

Cyclin-dependent kinase-5 (Cdk5) is required for neuronal survival, but its targets in the apoptotic pathways remain unknown. Here, we show that Cdk5 kinase activity prevents neuronal apoptosis through the upregulation of Bcl-2. Treatment of SH-SY5Y cells with retinoid acid (RA) and brain-derived neurotrophic factor (BDNF) generates differentiated neuron-like cells. DNA damage triggers apoptosis in the undifferentiated cells through mitochondrial pathway; however, RA/BDNF treatment results in Bcl-2 upregulation and inhibition of the mitochondrial pathway in the differentiated cells. RA/BDNF treatment activates Cdk5-mediated PI3K/Akt and ERK pathways. Inhibition of Cdk5 inhibits PI3K/Akt and ERK phosphorylation and Bcl-2 expression, and thus sensitizes the differentiated cells to DNA-damage. Inhibition of ERK, but not PI3K/Akt, abrogates Cdk5-medidated Bcl-2 upregulation and the protection of the differentiated cells. This study suggests that ERK-mediated Bcl-2 upregulation contributes to BDNF-induced Cdk5-mediated neuronal survival.

5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)- 1,2-isoxazoline as a useful rice herbicide

5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests.

New 2-phenyl-4,5,6,7-tetrahydro-2H-indazole derivatives as paddy field herbicides

A series of 3-chloro-2-(4-chloro-2-fluorophenyl)-4,5,6,7-tetrahydro-2H-indazole derivatives containing various substituted isoxazolinylmethoxy groups at the 5-position of the benzene ring were synthesized and their herbicidal activities assessed under greenhouse and flooded paddy conditions. Among them, compounds having a phenyl or cyano substituent at the 3-position of the 5-methyl-isoxazolin-5-yl structure demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 16-63 g AI ha(-1) under greenhouse conditions. Field trials indicated that these two compounds controlled a wide range of annual weeds rapidly with a good tolerance on transplanted rice seedlings by pre-emergence application. They showed a low mammalian and environmental toxicity in various toxicological tests.

The effects of dual blockade of the renin- angiotensin system on urinary protein and transforming growth factor-b excretion in 2 groups of patients with IgA and diabetic nephropathy

AIMS

The therapeutic benefits of dual blockade of the renin-angiotensin system (RAS) have been inconsistent on renal function and proteinuria. To know the contribution of the heterogeneity of study subjects to such inconsistency, we evaluated the effects of dual blockade of RAS in 2 groups of selected renal diseases, IgA and diabetic nephropathy. To avoid confounding by the blood pressure-reducing effects, angiotensin II receptor antagonists (ATRAs) were added on the patients with long-term, optimally controlled blood pressure taking ACE inhibitors. Twenty-four-hour urinary protein excretion rate and urinary TGF-beta1 level were measured as surrogate markers of renal injury.

METHODS

We conducted a prospective crossover trial with 14 IgA and 18 type-2-diabetic nephropathy patients showing moderate degree of proteinuria (> or = 1.0 g/day) and renal dysfunction (creatinine clearance 25 - 75/ml/min). Four to 8 mg once-daily dose of candesartan and placebo were alternatively added on ramipril dose of 5 - 7.5 mg/day for 16 weeks.

RESULTS

All baseline data except for the age factor were statistically the same between the 2 disease groups. Twenty-four-hour mean arterial blood pressures were 91.2 +/- 1.6 and 92.3 +/- 1.8 mmHg in IgA and diabetic nephropathy patients respectively at baseline (p = NS). Mean arterial pressure did not change by the addition of candesartan or placebo in both groups. The addition of candesartan (combination) reduced 24-hour urinary protein excretion rate in IgA nephropathy patients with a mean change of -12.3 +/- 4.5%, which is significantly greater compared to a mean change of -0.1 +/- 3.3% after the addition of placebo (placebo) (mean difference 12.4 +/- 5.0, 95% CI 1.2 - 23.5; p < 0.05). Urinary TGF-beta1 level was reduced considerably by the combination therapy, with a -28.9 +/- 6.0% decrease, which was significantly different to that by the placebo, with +4.3 +/- 12.4% (33.3 +/- 13.5, 3.2 - 63.3; p < 0.05). In diabetic nephropathy patients, the addition of candesartan did not reduce 24-hour urinary protein excretion rate. Mean changes of 24-hour urinary protein excretion rate were -0.8 +/- 4.7% by the combination therapy and +0.5 +/- 6.1% by placebo (mean difference 1.3 +/- 4.7, 95% CI -6.8 - 13.5; p < NS). The level of urinary TGF-beta1 was reduced by the combination therapy, with -14.3 +/- 9.5% decrease, but it did not reach statistical significance compared to placebo of +0.7 +/- 15.5% (15.0 +/- 13.5, -14.4 - 44.5; p < NS). The changes in 24-hour urinary protein excretion rate and urinary TGF-beta1 level were neither correlated with each other, nor with the change in mean arterial pressure. Significant changes in the renal function were not detected during the study period.

CONCLUSION

Definite beneficial effects of dual blockade of RAS on proteinuria and TGF-beta1 excretion were found in IgA nephropathy patients, which was independent of blood pressure-reducing effect. With our 16-week trial, such benefits were not observed in type 2 diabetic nephropathy. The reduction in urinary TGF-beta1 level suggests that the combination therapy may provide additional renoprotection through the antisclerosing effects. Based on our results, for a proper interpretation the therapeutic effects of the combination therapy should be evaluated separately according to the underlying renal disease.

Epidemiological typing of Streptococcus pneumoniae from various sources in India & Korea using Box A PCR fingerprinting

BACKGROUND & OBJECTIVES

Epidemiological typing of Streptococcus pneumoniae is necessary to study genetic relatedness among strains. The Box A PCR assay, a good epidemiological tool for high resolution typing of pneumococcal isolates, was used for comparison of strains of S. pneumoniae from Korea, an area of high penicillin resistance and India with low resistance to penicillin.

METHODS

The pneumococcal strains from Indian and Korean sources included in the study belonged to serotypes 19F, 23F, 6A & 6B. The penicillin susceptibility of the strains was confirmed by determination of minimum inhibitory concentration values. The strains were then fingerprinted using the Box A PCR protocol and the results were further analysed by Molecular Analyst Software.

RESULTS

The Box fingerprinting technique produced sharp, clear and reproducible banding patterns for strains of S. pneumoniae included in the study. There was no similarity between Indian and Korean strains at the genetic level. Among the Korean strains with similar serotypes, the level of similarity varied. Except for one pair (serotype 23F), that showed a level of homology of about 90 per cent, almost all the others showed less than 80 per cent homology. It was also seen that there was a high percentage of homology (> 90% in nasopharyngeal isolates from India belonging to serotype 19F) between isolates from similar source. Comparison of the Indian and Korean isolates of similar serotype showed low homology, except for one cluster of two strains with serotype 6B which showed 84 per cent homology (blood isolates from India and Korea).

INTERPRETATION & CONCLUSION

Box A PCR is a highly discriminatory and useful method for typing S. pneumoniae. The results of the study have shown low levels of homology between strains from within India and also between two geographically distinct areas.

Incisional hernia after corrective omentectomy for peritoneal dialysis catheter malposition

Laparotomic correction with or without omentectomy is occasionally required for malposition of a peritoneal dialysis (PD) catheter. We reviewed the incidence of incisional hernia following laparotomic PD catheter correction with or with omentectomy. From January 1996 to December 1998, PD catheters were implanted by non open-dissection technique using a trocar in 148 patients. Laparotomy for PD catheter malposition was required in 20 of the 148 patients. Omentectomy was performed simultaneously in 11 patients. After laparotomy, the wound was closed with interrupted or continuous layered polyglycolidelactide polymer sutures. Dialysis was resumed after the third or fourth day. Incisional hernia developed in 30% (6/20) of all patients undergoing laparotomy, but in none of the patients not undergoing laparotomy. The incidence increased when omentectomy was performed [5/11 (45.5%) vs 1/9 (11.1%)]. Multiparity, female sex, and laparotomy at a later time also predisposed to development of incisional hernia. Among the patients with incisional hernia, 2 patients showed multiple recurrences and 1 patient showed later leakage; PD catheters were lost in these patients. Another 3 patients continued continuous ambulatory peritoneal dialysis (CAPD) without a recurrence. The results suggest that incisional hernia is prevalent following laparotomic PD catheter correction, especially when omentectomy is performed simultaneously. Situations that seem to increase the risk of incisional hernia--inevitably encountered during corrective laparotomic omentectomy--are discussed. An evaluation is necessary concerning whether omentectomy acts as an independent risk factor for incisional hernia, and whether incisional hernia occurs more frequently when omentectomy is performed after a period on CAPD as compared with when it is performed at the time of PD catheter implantation. Laparotomic omentectomy should be performed as a last resort for the correction of PD catheter malposition.

Effects of ATP on TTX-sensitive and TTX-resistant sodium currents in rat sensory neurons

Differential effects of ATP on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium currents in rat dorsal root ganglion neurons were studied using the whole-cell variation of path-clamp technique. Currents were evoked by step depolarizations to 0 mV from a holding potential of -80 mV. ATP suppressed TTX-S sodium currents while it increased TTX-R sodium currents. The effects were concentration-dependent and were reversible upon washout with ATP-free external solution. ATP-gamma-S, a hydrolysis-resistant ATP analog, also affected two types of sodium currents similarly to ATP, excluding the possibility that the effects were caused by the products of ATP hydrolysis, namely adenosine. ATP by modulating sodium currents may exert profound effects on the transmission of sensory information such as nociception.

Pseudomonas aeruginosa as a potential cause of antibiotic-associated diarrhea

Although Pseudomonas aeruginosa is not generally considered as a cause of antibiotic-associated diarrhea, several cases of diarrhea caused by P. aeruginosa have been reported. We experienced seven cases of nosocomial diarrhea presumably caused by P. aeruginosa, which was the predominant organism isolated from stool cultures. Clostridium difficile toxin was also positive in one patient. No other potential or recognized enteropathogens were identified from stools. All patients had underlying diseases and had been receiving antibiotics before the diarrheal onset. All of the seven P. aeruginosa isolates were resistant to previously given antibiotics. Diarrhea stopped three days after withdrawal of probable offending antibiotics without specific treatment in two patients. The other five patients having continuous diarrhea despite withdrawal of probable offending antibiotics, were successfully treated with antipseudomonal agents. The median duration of diarrhea after the initiation of treatment was 6.3 days. These data suggest that P. aeruginosa can be a potential cause of antibiotic-associated diarrhea. Further investigations are warranted to evaluate the possible etiologic role of P. aeruginosa in antibiotic-associated diarrhea.

Fatal pulmonary-renal syndrome manifested with immune complex crescentic glomerulonephritis in a patient with MPO-ANCA seropositivity

Recent reports have indicated that a significant number of immune complex glomerulonephritis (GN) cases are associated with antineutrophilic cytoplasmic antibody (ANCA). However, most of the reported cases were associated with underlying primary glomerular diseases. When primary glomerular diseases were not found, immune deposits tended to be non-specific and the level of ANCA is usually borderline. We report here upon a case of life-threatening pulmonary-renal syndrome manifested simultaneously with immune complex GN and myeloperoxidase (MPO)-ANCA seropositivity. A 29- year-old man was admitted with pulmonary hemorrhage and rapidly progressing renal dysfunction. On admission, ANCA revealed perinuclear staining with a titer of 1:160. The MPO-ANCA level was 59 IU by ELISA. Other serologic markers including ANA, anti-DS-DNA and anti-GBM Ab were negative. Renal biopsy showed cellular crescents in eight of 18 glomeruli. Immunofluorescence staining showed strong granular deposits of C3, C1q, IgG and IgM in the capillary loop and the mesangium. Electron microscopy showed multifocal electron dense deposits scattered in the mesangium, paramesangium, and the subendothelial and subepithelial areas. The patient initially responded to steroid and cyclophosphamide. MPO-ANCA decreased to less than 10 IU. Twenty three days after hospital discharge, the patient was re-admitted urgently with fever, generalized papulonodular skin lesions, and a recurrence of massive pulmonary hemorrhage and renal dysfunction. He died from uncontrolled pulmonary hemorrhage and respiratory insufficiency. P-ANCA titer and MPO-ANCA level at the second admission were 1:320 and 82 U/ml respectively. Interestingly, relapse was shown to be triggered by varicella zoster infection.

Involvement of oxidative stress in ascorbate-induced proapoptotic death of PC12 cells

Ascorbate is a reducing agent, but it is also known to oxidize cellular components under specific conditions. The mechanism of this oxidative action, however, is not well established. Ascorbate treatment increased lipid peroxide content in PC12 cells, but did not increase quantities of lipid peroxide when homogenates of PC12 cells were treated with ascorbate, suggesting that cellular integrity is required for ascorbate to generate lipid peroxidation. However, dehydroascorbate increased lipid peroxide production in both intact PC12 cells and the cell homogenates. These differential effects of ascorbate and dehydroascorbate on intact cells versus homogenates suggest that the dehydroascorbate in cytosol induces an oxidative stress. Ascorbate in culture medium is rapidly oxidized to dehydroascorbate, which is transported into cells by a glucose transporter (GLUT). The GLUT antagonists wortmannin and cytochalasin B, or a high concentration of glucose, blocked (14)C uptake (from ascorbate) in a time-dependent manner and suppressed lipid peroxide production in PC12 cells. These observations support the concept that ascorbate is oxidized to dehydroascorbate, which is transported into cells via GLUT. The dehydroascorbate induces oxidative stress. The oxidative stress triggered apoptosis according to ceramide production, caspase-3 activation, and TUNEL. We have concluded that ascorbate is taken up after oxidation to dehydroascorbate via a "dehydroascorbate transporter" (GLUT), and the dehydroascorbate generates an oxidative stress which triggers apoptosis. These studies have significant implications for conditions under which a high concentration of ascorbate in a tissue is released during a period of hypoxia (e.g., stroke) and taken up during a reperfusion period as dehydroascorbate. Inhibiting uptake of dehydroascorbate may offer novel therapeutic strategies to alleviate brain damage during a reperfusion period.

Carriage of antibiotic-resistant pneumococci among Asian children: a multinational surveillance by the Asian Network for Surveillance of Resistant Pathogens (ANSORP)

To investigate the nasal carriage of antibiotic-resistant pneumococci by children, anterior nasal swabs were done for 4963 children <5 years old in 11 countries in Asia and the Middle East. In total, 1105 pneumococci isolates (carriage rate, 22.3%) were collected, 35.8% of which were found to be nonsusceptible to penicillin. Prevalence of penicillin nonsusceptibility was highest in Taiwan (91.3%), followed by Korea (85.8%), Sri Lanka (76.5%), and Vietnam (70.4%). Penicillin resistance was related to residence in urban areas, enrollment in day care, and a history of otitis media. The most common serogroups were 6 (21.5%), 23 (16.5%), and 19 (15.7%). The most common clone, as assessed by pulsed-field gel electrophoresis, was identical to the Spanish 23F clone and to strains of invasive isolates from adult patients. Data in this study documented the high rate of penicillin or multidrug resistance among isolates of pneumococci carried nasally in children in Asia and the Middle East and showed that this is due to the spread of a few predominant clones in the region.

Peripheral blood mitochondrial DNA content is inversely correlated with insulin secretion during hyperglycemic clamp studies in healthy young men

Abnormalities in mitochondrial DNA(mtDNA) have been implicated in the pathogenesis of diabetes mellitus. We recently reported that decreased mtDNA content precedes the development of diabetes mellitus and is associated with parameters of insulin resistance. In this study, we examined whether there is any relation between mtDNA content and insulin secretion. We compared the mtDNA content of peripheral blood leukocytes with the parameters of insulin secretion measured by hyperglycemic clamp in a group of healthy young men. There were statistically significant correlations between mtDNA content in peripheral blood and fasting plasma insulin (r=-0.43, P<0.05) and C-peptide levels (r=-0.44, P<0.05). MtDNA content also correlated negatively with acute insulin response(r=-0.48, P<0.05), late insulin response (r=-0.50, P<0.05) during hyperglycemic clamp and insulin secretion after glucagon stimulation (r=-0.60, P<0.01). mtDNA content in peripheral blood correlated negatively with homeostasis model (HOMA) insulin resistance (r=-0.45, P<0.05) although it did not correlate with the insulin insensitivity index (M/I) during hyperglycemic clamp. In summary, the mtDNA content of peripheral blood correlated negatively with indices of insulin resistance and insulin secretion in healthy young men. The compensatory response of pancreas beta cells to insulin resistance might contribute in part to increased insulin secretion in these subjects.