Pregabalin and lacosamide ameliorate paclitaxel-induced peripheral neuropathy via inhibition of JAK/STAT signaling pathway and Notch-1 receptor

Anticonvulsant drugs such as pregabalin (PGB) and lacosamide (LCM), exhibit potent analgesic effects in diabetic neuropathy; however, their possible role/mechanisms in paclitaxel (PTX)-induced peripheral neuropathy have not been elucidated, which is the aim of the present study. Neuropathic pain was induced in rats by injecting PTX (2 mg/kg, i. p) on days 0, 2, 4 and 6. Forty eight hours after the last dose of PTX, rats were treated orally with 30 mg/kg/day of either PGB or LCM for 21 days. Both therapies improved thermal hyperalgesia and cold allodynia induced by PTX. Interestingly, LCM therapy showed no motor impairment that was observed upon using PGB, as demonstrated using rotarod test. Treatment with PGB or LCM restored the sciatic nerve content of the depleted total antioxidant capacity (TAC) and nerve growth factor (NGF), and lessened the elevated contents of nuclear factor kappa B p65 (NF-kB p65), tumor necrosis factor-α (TNF-α), and active caspase-3. On the molecular level, the drugs reduced the protein expression of Notch1 receptor, phosphorylated p38 mitogen-activated protein kinase (p-p38-MAPK), and the trajectory interleukin-6/phosphorylated janus kinase 2/phosphorylated signal transducer and activator of transcription 3 (IL-6/p-JAK2/p-STAT3). Therefore, the current study demonstrated a pivotal role for LCM in the management of PTX-induced peripheral neuropathy similar to PGB, but without motor adverse effects via the inhibition of oxidative stress, inflammation and apoptosis, as well as IL-6/JAK/STAT pathway and Notch1 receptor over-expression.

The association between childhood fractures and adolescence bone outcomes: a population-based study, the Tromsø Study, Fit Futures

Childhood fracture may predict persistent skeletal fragility, but it may also reflect high physical activity which is beneficial to bone development. We observe a difference in the relationship between previous fracture and bone outcome across physical activity level and sex. Further elaboration on this variation is needed.

PURPOSE

Childhood fracture may be an early marker of skeletal fragility, or increased levels of physical activity (PA), which are beneficial for bone mineral accrual. This study investigated the association between a previous history of childhood fracture and adolescent bone mineral outcomes by various PA levels.

METHODS

We recruited 469 girls and 492 boys aged 15-18 years to this study. We assessed PA levels by questionnaire and measured areal bone mineral density (aBMD) and bone mineral content (BMC) using dual-energy X-ray absorptiometry (DXA) at arm, femoral neck (FN), total hip (TH), and total body (TB) and calculated bone mineral apparent density (BMAD, g/cm³). Fractures from birth to time of DXA measurements were retrospectively recorded. We analyzed differences among participants with and without fractures using independent sample t test. Multiple linear regression was used to examine the association between fractures and aBMD and BMC measurements according to adolescent PA.

RESULTS

Girls with and without a previous history of fracture had similar BMC, aBMD, and BMAD at all sites. In multiple regression analyses stratified by physical activity intensity (PAi), there was a significant negative association between fracture and aBMD-TH and BMC-FN yet only in girls reporting low PAi. There was a significant negative association between forearm fractures, BMAD-FN, and BMAD-arm among vigorously active boys.

CONCLUSION

Our findings indicate a negative association between childhood fractures and aBMD/BMC in adolescent girls reporting low PAi. In boys, such an association appears only in vigorously active participants with a history of forearm fractures.

Combination of carvacrol with simvastatin improves the lipid-lowering efficacy and alleviates simvastatin side effects

The present investigation was designed to examine the possible additive hypolipidemic effect of carvacrol (CARV) in combination with simvastatin (SIM) on poloxamer 407 (P407)-induced hyperlipidemia. Rats were injected with P407, (500 mg/ kg; i.p.), twice a week, for 30 days. Treatment was carried out by administration of SIM (20 mg/kg/day; p.o.) or CARV (50 mg/kg/day; p.o.) or combination of them. Treatment with CARV significantly decreased total cholesterol, triglycerides, low-density lipoprotein, atherogenic index, leptin, and increased high-density lipoprotein and adiponectin. Moreover, CARV potentiated the hypolipidemic effect of SIM. Both SIM and CARV alleviated the oxidative stress induced by P407. Interestingly, CARV, when combined with SIM, significantly ameliorated SIM-induced liver and muscle injury by reducing the level of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and myoglobin and restoring the normal histological picture of both liver and muscle as well as apoptosis.

Pinocembrin ex vivo preconditioning improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats

Pulmonary hypertension is still not curable and the available current therapies can only alleviate symptoms without hindering the progression of disease. The present study was directed to investigate the possible modulatory effect of pinocembrin on endothelial progenitor cells transplanted in monocrotaline-induced pulmonary hypertension in rats. Pulmonary hypertension was induced by a single subcutaneous injection of monocrotaline (60mg/kg). Endothelial progenitor cells were in vitro preconditioned with pinocembrin (25mg/L) for 30min before being i.v. injected into rats 2weeks after monocrotaline administration. Four weeks after monocrotaline administration, blood pressure, electrocardiography and right ventricular systolic pressure were recorded. Rats were sacrificed and serum was separated for determination of endothelin-1 and asymmetric dimethylarginine levels. Right ventricles and lungs were isolated for estimation of tumor necrosis factor-alpha and transforming growth factor-beta contents as well as caspase-3 activity. Moreover, protein expression of matrix metalloproteinase-9 and endothelial nitric oxide synthase in addition to myocardial connexin-43 was assessed. Finally, histological analysis of pulmonary arteries, cardiomyocyte cross-sectional area and right ventricular hypertrophy was performed and cryosections were done for estimation of cell homing. Preconditioning with pinocembrin provided a significant improvement in endothelial progenitor cells' effect towards reducing monocrotaline-induced elevation of inflammatory, fibrogenic and apoptotic markers. Furthermore, preconditioned cells induced a significant amelioration of endothelial markers and cell homing and prevented monocrotaline-induced changes in right ventricular function and histological analysis compared with native cells alone. In conclusion, pinocembrin significantly improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats.

Excess mortality after hip fracture in elderly persons from Europe and the USA: the CHANCES project

BACKGROUND

Hip fractures are associated with diminished quality of life and survival especially amongst the elderly.

OBJECTIVE

All-cause mortality after hip fracture was investigated to assess its magnitude.

METHODS

A total of 122 808 participants from eight cohorts in Europe and the USA were followed up for a mean of 12.6 years, accumulating 4273 incident hip fractures and 27 999 deaths. Incident hip fractures were assessed through telephone interviews/questionnaires or national inpatient/fracture registries, and causes of death were verified with death certificates. Cox proportional hazards models and the time-dependent variable methodology were used to assess the association between hip fracture and mortality and its magnitude at different time intervals after the injury in each cohort. We obtained the effect estimates through a random-effects meta-analysis.

RESULTS

Hip fracture was positively associated with increased all-cause mortality; the hazard ratio (HR) in the fully adjusted model was 2.12, 95% confidence interval (CI) 1.76-2.57, after adjusting for potential confounders. This association was stronger amongst men [HR: 2.39, 95% CI: 1.72-3.31] than amongst women [HR: 1.92, 95% CI: 1.54-2.39], although this difference was not significant. Mortality was higher during the first year after the hip fracture [HR: 2.78, 95% CI: 2.12-3.64], but it remained elevated without major fluctuations after longer time since hip fracture [HR (95% CI): 1.89 (1.50-2.37) after 1-4 years; 2.15 (1.81-2.55) after 4-8 years; 1.79 (1.57-2.05) after 8 or more years].

CONCLUSION

In this large population-based sample of older persons across eight cohorts, hip fracture was associated with excess short- and long-term all-cause mortality in both sexes.

Anti-diabetic and renoprotective effects of aliskiren in streptozotocin-induced diabetic nephropathy in female rats

Since chronic kidney disease due to diabetic nephropathy (DN) is becoming an ever larger health burden worldwide, more effective therapies are desperately needed. In the present study, the anti-diabetic and renoprotective effects of aliskiren have been evaluated in streptozotocin (STZ)-induced DN in rats. DN was induced by a single intraperitoneal injection of STZ (65 mg/kg). Three weeks after STZ, rats were divided into four groups; normal, diabetic, diabetic treated with gliclazide (10 mg/kg/day) for 1 month, and diabetic treated with aliskiren (50 mg/kg/day) for 1 month. At the end of the experiment, mean arterial blood pressure and heart rate were recorded. Rats were then euthanized and serum was separated for determination of glucose, insulin, kidney function tests, superoxide dismutase activity (SOD), adiponectin, and tumor necrosis factor-alpha (TNF-α). One kidney was used for estimation of malondialdehyde (MDA), reduced glutathione (GSH), and nitric oxide (NO) contents. Other kidney was used for histopathological study and immunohistochemical measurement of caspase-3 and transforming growth factor beta (TGF-β). In addition, islets of Langerhans were isolated from normal rats by collagenase digestion technique for in vitro study. Aliskiren normalized STZ-induced hyperglycemia, increased insulin level both in vivo and in vitro, normalized kidney function tests and blood pressure, and alleviated STZ-induced kidney histopathological changes. This could be related to the ability of aliskiren toward preserving hemodynamic changes and alleviating oxidative stress and inflammatory and apoptotic markers induced by STZ in rats. However, aliskiren was more effective than gliclazide in relieving STZ-induced DN. These findings support the beneficial effect of aliskiren treatment in DN which could be attributed to its anti-diabetic, renoprotective, antioxidant, anti-inflammatory, and anti-apoptotic effects. Moreover, clinical studies are required to establish the effectiveness of aliskiren treatment in patients suffering from hypertension and diabetes.

Nicorandil enhances the efficacy of mesenchymal stem cell therapy in isoproterenol-induced heart failure in rats

Stem cell transplantation has emerged as a promising technique for regenerative medicine in cardiovascular therapeutics. However, the results have been less than optimal. The aim of the present study was to investigate whether nicorandil could offer an additional benefit over bone marrow-derived mesenchymal stem cell therapy in isoproterenol-induced myocardial damage and its progression to heart failure in rats. Isoproterenol was injected subcutaneously for 2 consecutive days at doses of 85 and 170 mg/kg/day, respectively. Nicorandil (3 mg/kg/day) was then given orally with or without a single intravenous bone marrow-derived mesenchymal stem cell administration. Electrocardiography and echocardiography were recorded 2 weeks after the beginning of treatment. Rats were then sacrificed and the ventricle was isolated for estimation of tumor necrosis factor-alpha, vascular endothelial growth factor and transforming growth factor-beta. Moreover, protein expressions of caspase-3, connexin-43 as well as endothelial and inducible nitric oxide synthases were evaluated. Finally, histological studies of myocardial fibrosis and blood vessel density were performed and cryosections were done for estimation cell homing. Combined nicorandil/bone marrow-derived mesenchymal stem cell therapy provided an additional improvement compared to cell therapy alone toward reducing isoproterenol-induced cardiac hypertrophy, fibrosis and inflammation. Notably, combined therapy induced significant increase in angiogenesis and cell homing and prevented isoproterenol-induced changes in contractility and apoptotic markers. In conclusion, combined nicorandil/bone marrow-derived mesenchymal stem cell therapy was superior to cell therapy alone toward preventing isoproterenol-induced heart failure in rats through creation of a supportive environment for mesenchymal stem cells.

Education, marital status, and risk of hip fractures in older men and women: the CHANCES project

The role of socioeconomic status in hip fracture incidence is unclear. In a diverse population of elderly, higher education was found to be associated with lower, whereas living alone, compared to being married/cohabiting, with higher hip fracture risk. Educational level and marital status may contribute to hip fracture risk.

INTRODUCTION

The evidence on the association between socioeconomic status and hip fracture incidence is limited and inconsistent. We investigated the potential association of education and marital status with hip fracture incidence in older individuals from Europe and USA.

METHODS

A total of 155,940 participants (79 % women) aged 60 years and older from seven cohorts were followed up accumulating 6456 incident hip fractures. Information on education and marital status was harmonized across cohorts. Hip fractures were ascertained through telephone interviews/questionnaires or through record linkage with registries. Associations were assessed through Cox proportional hazard regression adjusting for several factors. Summary estimates were derived using random effects models.

RESULTS

Individuals with higher education, compared to those with low education, had lower hip fracture risk [hazard ratio (HR) = 0.84, 95 % confidence interval (CI) 0.72-0.95]. Respective HRs were 0.97 (95 % CI 0.82-1.13) for men and 0.75 (95 % CI 0.65-0.85) for women. Overall, individuals living alone, especially those aged 60-69 years, compared to those being married/cohabiting, tended to have a higher hip fracture risk (HR = 1.12, 95 % CI 1.02-1.22). There was no suggestion for heterogeneity across cohorts (P heterogeneity > 0.05).

CONCLUSIONS

The combined data from >150,000 individuals 60 years and older suggest that higher education may contribute to lower hip fracture risk. Furthermore, this risk may be higher among individuals living alone, especially among the age group 60-69 years, when compared to those being married/cohabiting.

Tempol, a superoxide dismutase mimetic agent, ameliorates cisplatin-induced nephrotoxicity through alleviation of mitochondrial dysfunction in mice

Background

Mitochondrial dysfunction is a crucial mechanism by which cisplatin, a potent chemotherapeutic agent, causes nephrotoxicity where mitochondrial electron transport complexes are shifted mostly toward imbalanced reactive oxygen species versus energy production. In the present study, the protective role of tempol, a membrane-permeable superoxide dismutase mimetic agent, was evaluated on mitochondrial dysfunction and the subsequent damage induced by cisplatin nephrotoxicity in mice.

Methods and Findings

Nephrotoxicity was assessed 72 h after a single i.p. injection of cisplatin (25 mg/kg) with or without oral administration of tempol (100 mg/kg/day). Serum creatinine and urea as well as glucosuria and proteinuria were evaluated. Both kidneys were isolated for estimation of oxidative stress markers, adenosine triphosphate (ATP) content and caspase-3 activity. Moreover, mitochondrial oxidative phosphorylation capacity, complexes I–IV activities and mitochondrial nitric oxide synthase (mNOS) protein expression were measured along with histological examinations of renal tubular damage and mitochondrial ultrastructural changes. Tempol was effective against cisplatin-induced elevation of serum creatinine and urea as well as glucosuria and proteinuria. Moreover, pretreatment with tempol notably inhibited cisplatin-induced oxidative stress and disruption of mitochondrial function by restoring mitochondrial oxidative phosphorylation, complexes I and III activities, mNOS protein expression and ATP content. Tempol also provided significant protection against apoptosis, tubular damage and mitochondrial ultrastructural changes. Interestingly, tempol did not interfere with the cytotoxic effect of cisplatin against the growth of solid Ehrlich carcinoma.

Conclusion

This study highlights the potential role of tempol in inhibiting cisplatin-induced nephrotoxicity without affecting its antitumor activity via amelioration of oxidative stress and mitochondrial dysfunction.

Naringenin adds to the protective effect of L-arginine in monocrotaline-induced pulmonary hypertension in rats: favorable modulation of oxidative stress, inflammation and nitric oxide

The present study was directed to investigate the possible modulatory effect of naringenin when co-administered with L-arginine in monocrotaline-induced pulmonary hypertension in rats. Pulmonary hypertension was induced by a single subcutaneous injection of monocrotaline (60 mg/kg). L-arginine (500 mg/kg) and naringenin (50 mg/kg) were orally administered daily, alone and in combination, for 3 weeks. Mean arterial blood pressure, electrocardiography and echocardiography were then recorded and rats were sacrificed and serum was separated for determination of total nitrate/nitrite level. Right ventricles and lungs were isolated for estimation of oxidative stress markers, tumor necrosis factor-alpha, total nitrate/nitrite and transforming growth factor-beta. Myeloperoxidase and caspase-3 activities in addition to endothelial and inducible nitric oxide synthase protein expression were also determined. Moreover, histological analysis of pulmonary arteries and cardiomyocyte cross-sectional area was performed. Combined therapy provided a significant improvement in L-arginine protective effect toward preserving hemodynamic changes and alleviating oxidative stress, inflammatory and apoptotic markers induced by monocrotaline treatment. Furthermore, combined therapy prevented monocrotaline-induced changes in endothelial and inducible nitric oxide synthase protein expression as well as histological analysis compared with either treatment alone. In conclusion, naringenin significantly adds to the protective effect of L-arginine in pulmonary hypertension induced by monocrotaline in rats.

Exploring the protective role of apocynin, a specific NADPH oxidase inhibitor, in cisplatin-induced cardiotoxicity in rats

Despite the clinical reports, few studies have focused on reducing the cardiotoxicity of cisplatin. In the present study, cardiotoxicity was examined after a single ip injection of cisplatin (7mg/kg) in rats. Apocynin was given in drinking water (600mg/L) for five successive days before and after cisplatin injection. At the end of the experiment, hemodynamic parameters were recorded, animals were sacrificed and serum creatine kinase-MB activity was determined. The whole ventricle was isolated for estimation of tumor necrosis factor-alpha (TNF-α) content, NADPH oxidase, myeloperoxidase and caspase-3 activities in addition to nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and nuclear factor kappa B (NF-κB) gene expressions. Furthermore, oxidative stress markers and antioxidant enzymes were measured in postmitochondrial and mitochondrial fractions. Mitochondrial membrane potential, nuclear DNA fragmentation and cardiomyocyte cross-sectional area were also evaluated. Apocynin was effective against cisplatin-induced decrement in heart rate and blood pressure. Moreover, pretreatment with apocynin notably ameliorated the state of oxidative stress, mitigated inflammation and preserved mitochondrial membrane potential. Apocynin provided also a significant cardioprotection as revealed by alleviating the overexpression of Nrf2, HO-1 and NF-κB, the elevation of caspase-3 activity, the prominent nuclear DNA fragmentation and the decreased cardiomyocyte cross-sectional area. This study highlights the potential role of apocynin in inhibiting cisplatin-induced hemodynamic changes, postmitochondrial and mitochondrial damage as indicated by improvement in the state of oxidative stress, inflammation and apoptosis.

Nicorandil ameliorates mitochondrial dysfunction in doxorubicin-induced heart failure in rats: possible mechanism of cardioprotection

Despite of its known cardiotoxicity, doxorubicin is still a highly effective anti-neoplastic agent in the treatment of several cancers. In the present study, the cardioprotective effect of nicorandil was investigated on hemodynamic alterations and mitochondrial dysfunction induced by cumulative administration of doxorubicin in rats. Doxorubicin was injected i.p. over 2 weeks to obtain a cumulative dose of 18 mg/kg. Nicorandil (3 mg/kg/day) was given orally with or without doxorubicin treatment. Heart rate and aortic blood flow were recorded 24 h after receiving the last dose of doxorubicin. Rats were then sacrificed and hearts were rapidly excised for estimation of caspase-3 activity, phosphocreatine and adenine nucleotides contents in addition to cytochrome c, Bcl2, Bax and caspase 3 expression. Moreover, mitochondrial oxidative phosphorylation capacity, creatine kinase activity and oxidative stress markers were measured together with the examination of DNA fragmentation and ultrastructural changes. Nicorandil was effective in alleviating the decrement of heart rate and aortic blood flow and the state of mitochondrial oxidative stress induced by doxorubicin cardiotoxicity. Nicorandil also preserved phosphocreatine and adenine nucleotides contents by restoring mitochondrial oxidative phosphorylation capacity and creatine kinase activity. Moreover, nicorandil provided a significant cardioprotection via inhibition of apoptotic signaling pathway, DNA fragmentation and mitochondrial ultrastructural changes. Interestingly, nicorandil did not interfere with cytotoxic effect of doxorubicin against the growth of solid Ehrlich carcinoma. In conclusion, nicorandil was effective against the development of doxorubicin-induced heart failure in rats as indicated by improvement of hemodynamic perturbations, mitochondrial dysfunction and ultrastructural changes without affecting its antitumor activity.

Does recalled dieting increase the risk of non-vertebral osteoporotic fractures? The Tromsø Study

The risk of non-vertebral osteoporotic fractures increased by increasing recalled amount of weight loss when dieting in women aged ≥ 46 years and in those with BMI < 25 kg/m(2) participating in the Tromsø Study (1994/1995-2009). The increased risk was present both in women with few and several episodes of recalled dieting.

INTRODUCTION

The influence of repeated dieting on bone health is uncertain. This study aims to investigate whether recalled dieting is a risk factor for non-vertebral osteoporotic fractures.

METHODS

In 1994/1995 weight and height were measured in all participants aged 25-69 years in the population-based Tromsø Study. Information about socioeconomic background, diseases and lifestyle factors was collected by questionnaires-including number of recalled dieting episodes and largest amount of weight loss when dieting. The participating 20,745 women and men were followed for 15 years, fractures were registered from X-ray archives and analysed by Cox's proportional hazards models.

RESULTS

Among those who recalled dieting, 975 women and 364 men suffered a non-vertebral osteoporotic fracture during follow-up. Compared to women without recalled weight loss when dieting, women who reported their largest weight loss of 11 kg or more had a hazard ratio (HR) = 1.48 (95% CI 1.13-1.94) for osteoporotic fracture, adjusted for age, marital status, body mass index, height, education, physical activity, smoking, alcohol intake, history of cardiovascular disease and psychological distress. The increased risk was statistically significant only in women aged ≥ 46 years and in those with BMI < 25 kg/m(2). Women who recalled ≥ 11 dieting episodes had HR = 1.73 (CI 1.11-2.68) for osteoporotic fracture compared to those with no recalled episodes. Dieting was not associated with risk of fractures in men, but the number of fractures was low.

CONCLUSIONS

The increased risk of non-vertebral osteoporotic fractures by recalled dieting in women indicates that maintenance of a stable weight may have beneficial effects on fracture risk.

Cardioprotective effects of ozone oxidative preconditioning in an in vivo model of ischemia/reperfusion injury in rats

BACKGROUND

Several studies have demonstrated the beneficial effects of ozone oxidative preconditioning in several pathologies characterized by cellular oxidative and inflammatory burden. The present study was designed to investigate the cardioprotective effects of oxidative preconditioning in ischemia/reperfusion (I/R) injury.

METHODS

Rats were randomly assigned into five groups. Groups 1 and 2 were normal and I/R groups, respectively. Two of the other groups received two different doses of ozone therapies by rectal insufflations. The last group received vehicle (oxygen). Rats were subjected to myocardial I/R (40 min/10 min). Heart rate and ventricular arrhythmias were recorded during I/R progress. At the end of reperfusion, plasma creatine kinase-MB (CK-MB) activity and total nitrate/nitrite (NO(x)) were determined. In addition, lactate, adenine nucleotides, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and myeloperoxidase (MPO) activity were estimated in the heart left ventricle. Histological examination was also performed to visualize the protective cellular effects.

RESULTS

Both doses of ozone therapy were equally protective in reducing CK-MB release. However, the higher dose was more effective in reducing oxidative stress, lactate accumulation, elevated MPO activity and plasma NO(x) as well as preserving myocardial adenine nucleotides. Histological examination also revealed better improvement with a higher dose of ozone therapy compared to the I/R group.

CONCLUSION

Ozone therapy can afford significant cardioprotection against biochemical and histological changes associated with I/R injury.

Comparative study of the cardioprotective effects of local and remote preconditioning in ischemia/reperfusion injury

AIMS

Though the cardioprotective effects of local or remote preconditioning have been estimated, it is still unclear which of them is more reliable and provides more cardioprotection. The present investigation was directed to compare, in one study, the cardioprotective effects of different cycles of local or remote preconditioning in ischemia/reperfusion (I/R)-induced electrophysiological, biochemical and histological changes in rats.

MAIN METHODS

Rats were randomly assigned into 10 groups. Groups 1 and 2 were normal and I/R groups, respectively. Other groups were subjected to 1, 2, 3, 4 cycles of local or remote preconditioning before myocardial I/R (40 min/10 min). Heart rate and ventricular arrhythmias were recorded during I/R progress. At the end of reperfusion, plasma creatine kinase-MB (CK-MB) activity and total nitrate/nitrite (NO(x)) were determined. In addition, lactate, adenine nucleotides, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and myeloperoxidase (MPO) activity were estimated in the heart left ventricle. Histological examination was also performed to visualize the protective cellular effects of the effective cycle of local or remote preconditioning.

KEY FINDINGS

In general, local preconditioning was more effective than remote preconditioning in reducing ventricular arrhythmias, CK-MB release, lactate accumulation and elevated MPO activity as well as preserving adenine nucleotides. Concerning the most effective group in each therapy, 3 cycles of local preconditioning provided more cardioprotection than that of remote preconditioning in the histological examination.

SIGNIFICANCE

Despite being invasive, local preconditioning provided more effective cardioprotection than remote preconditioning in ameliorating the overall electrophysiological, biochemical and histological changes.

Hip fractures in a city in Northern Norway over 15 years: time trends, seasonal variation and mortality : the Harstad Injury Prevention Study

In this open population-based study from Northern Norway, there was no increase in hip fracture incidence in women and men from 1994 to 2008. Age-adjusted hip fracture rates was lower compared to reported rates from the Norwegian capital Oslo, indicating regional differences within the country.

INTRODUCTION

The aim of the present population-based study was to describe age- and sex-specific incidence of hip fractures in a Northern Norwegian city, compare rates with the Norwegian capital Oslo, describe time trends in hip fracture incidence, place of injury, seasonal variation and compare mortality after hip fracture between women and men.

METHODS

Data on hip fractures from 1994 to 2008 in women and men aged 50 years and above were obtained from the Harstad Injury Registry.

RESULTS

There were altogether 603 hip fractures in Harstad between 1994 and 2008. The annual incidenc rose exponentially from 5.8 to 349.2 per 10,000 in men, and from 8.7 to 582.2 per 10,000 in women from the age group 50-54 to 90+ years. The age-adjusted incidence rates were 101.0 and 37.4 in women and men, respectively, compared to 118.0 in women (p = 0.005) and 44.0 in men (p = 0.09) in Oslo. The age-adjusted incidence rates did not increase between 1994-1996 and 2006-2008. The majority of hip fractures occurred indoors and seasonal variation was significant in fractures occurring outdoors only. After adjusting for age at hip fracture, mortality after fracture was higher in men than in women 3, 6 and 12 months (p ≤ 0.002) after fracture.

CONCLUSIONS

There are regional differences in hip fracture incidence that cannot be explained by a north-south gradient in Norway. Preventive strategies must be targeted to indoor areas throughout the year and to outdoor areas in winter.

BMI change is associated with fracture incidence, but only in non-smokers. The Tromsø Study

Few studies have examined the association between body mass index (BMI) change and fracture in a general population. We observed that BMI loss was associated with increased fracture risk in non-smoking men and women, but not in smokers. BMI gain was associated with decreased fracture risk in women.

INTRODUCTION

Weight loss has been associated with increased fracture risk, but few studies have included men. The aim of this study was to examine the association between BMI change and fracture risk in both genders.

METHODS

A population-based cohort study in Tromsø, Norway, of adults, aged 20 to 54 years in 1979, who participated in two or three health surveys in 1979-1980, 1986-1987, and 1994-1995. Weight and height were measured at each survey. Information about lifestyle was obtained by questionnaires. Poisson regression was used to estimate incidence rates and Cox proportional hazards regression model to assess the association between fracture risk and BMI change. Fractional polynomials were used to accommodate non-linear associations.

RESULTS

A total of 5,549 men and 5,428 women participated. There were 1,135 fractures during 10 years of follow-up. Reduction in BMI was associated with increased non-vertebral fracture risk in non-smokers, but not in smokers. The hazard ratio in male and female non-smokers per 10-year BMI decrease of 2 kg/m(2) versus a BMI increase of 1 kg/m(2) was 1.79 (95% confidence interval (CI), 1.17-2.75) and 1.60 (95% CI, 1.28-1.99), respectively. The association was not significantly modified by initial BMI or age or by exclusion of subjects with cardiovascular diseases, diabetes, or cancer. In female non-smokers, weight gain was inversely associated with fracture risk.

CONCLUSIONS

In a general Norwegian population, reduction in BMI was significantly associated with increased fracture risk in male and female non-smokers, but not in smokers. These findings could not be explained by preexisting disease.

Bone loss and the risk of non-vertebral fractures in women and men: the Tromsø study

SUMMARY

We assessed the association between the rate of forearm bone loss and non-vertebral fracture. Bone loss at the distal forearm predicted fractures, independently of baseline BMD, but not independently of follow-up BMD in women. The BMD level where an individual ends up is the significant predictor of fracture risk.

INTRODUCTION

Bone loss may predict fracture risk independently of baseline BMD. The influence of follow-up BMD on this prediction is unknown. The aim of this study was to assess the association between bone loss and fracture risk in both sexes in a prospective population-based study.

METHODS

We included 1,208 postmenopausal women (50 to 74 years), and 1,336 men (55 to 74 years) from the Tromsø Study, who had repeated distal and ultra-distal forearm BMD measurements. Non-vertebral fractures were registered from 2001 to 2005.

RESULTS

A total of 100 women and 46 men sustained fractures during the follow-up time. Independent of baseline BMD, the RR associated with distal site bone loss of 1 SD %/year was 1.23 (1.01-1.50) for low-trauma fractures (excluding hand, foot, skull & high-trauma) and 1.32 (1.07-1.62) for osteoporotic fractures (hip, wrist and shoulder). However, bone loss did not predict fracture after adjusting for follow-up BMD. The BMD level where an individual ends up became the significant predictor of fracture risk and not the rate of bone loss. Follow-up BMD at ultra-distal site was associated with low-trauma fractures in both sexes. While ultra-distal site BMD changes were not associated with fracture risk in both sexes.

CONCLUSION

Bone loss at the distal forearm predicted non-vertebral fractures, independently of baseline BMD, but not independently of follow-up BMD, in women. The BMD level where an individual ends up is the significant predictor of fracture risk and not the rate of bone loss.